Polymerization of Zr (IV) in an oxynitrate solution: effects on the nucleation and aggregation of hydrated ZrO2

Polymerization of Zr (IV) in an oxynitrate solution: effects on the nucleation and aggregation of hydrated ZrO2 | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Polymerization of Zr (IV) in an oxynitrate solution: effects on the nucleation and aggregation of hydrated ZrO 2 Maksim Mashkovtsev, Evgenie Baksheev, Maksim Domashenkov, Denis Khionin, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6175824/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 01 Jul, 2025 Read the published version in Chemical Papers → Version 1 posted 5 You are reading this latest preprint version Abstract In this study, the effect of the Zr(IV) polymerization degree in a nitric acid solution on the characteristics of hydrated zirconia particles and zirconia powders was investigated. Samples of hydrated zirconia were produced via the controlled double-jet precipitation (CDJP) method. The degree of Zr (IV) polymerization in the solution was varied by modifying the NO 3 /ZrO 2+ ratio. The properties of the hydrated zirconia particles and zirconia powders formed after calcination were investigated via laser diffraction, optical and scanning electron microscopy, X-ray phase analysis, thermogravimetry and BET. The polymerization of Zr (IV) involves the formation and elongation of polymer chains consisting of tetramers of Zr 4 (OH) 8 (NO 3 ) 8 . An increase in the degree of Zr (IV) polymerization leads to a decrease in the size of the crystallites and an increase in the diameter of the primary particles. This facilitated the formation of dense aggregates with significantly reduced macroporosity. The mechanism of particle aggregation obtained by the CDJP method from a zirconium oxynitrate solution with different degrees of Zr(IV) polymerization was established and discussed in detail. Hydrated zirconia xerogel zirconia powder olation oxolation zirconium polymerization population balance method Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Introduction Zirconia is a material with a wide range of applications in modern industry. These include use as a support in catalysts, biocompatible ceramics in dentistry and orthopedics (Gali 2018; Catauro 2019; Pandey 2014), electrodes and high-temperature electrochemical devices with electrolytes (Xi 2014; Prakash 2014; Yue 2019; Xi 2014), and many other areas. The key characteristics of zirconia powders are particle size, shape and dispersibility. Currently, various methods are used to synthesize zirconia powders with controlled properties: the emulsion method (Liu 2019; Shi 2020), sol-gel method (Widoniak 2005; Widoniak 2005; Liang 2020; Yaon 2015; Uchiyama 2012), hydrothermal (Agamy 2023) and spray-drying method (Pan 2011; Kim 2007; Garcia 2011; Chen 2021). These methods facilitate the production of zirconia powders with a regular particle shape and size, ranging from a few to hundreds of micrometers. However, the aforementioned methods are typically quite complex and labor intensive, which increases the cost of narrowly dispersed zirconia powder and constrains its applicability. The controlled double-jet precipitation (CDJP) method is widely used for a wide range of powder species synthesis, particularly the ZrO 2 . This method enables precise control of the synthesis conditions, including the pH value, degree of supersaturation, and rate of reagent introduction into the reaction medium. Accordingly, the CDJP method is considered the most effective in terms of regulating the key properties of powder materials, including dispersibility, morphology and phase composition (Stavek 1992; Chen 2019; Stavek 1990). The CDJP process involves the nucleation of primary particles and their subsequent growth through the Ostwald ripening mechanism, in addition to layer-by-layer aggregation of unstable colloidal particles (Stavek 1992). The influence of CDJP conditions on the nucleation and aggregation of hydrated zirconia and on the properties of zirconia powder has been well studied in our previous studies. In (Buinachev 2021), the phenomenon of layer-by-layer aggregation of hydrated zirconia particles was detected and interpreted, allowing the preparation of monodisperse zirconia powders in a narrow pH range. The effect of pH precipitation on the aggregation mechanism of hydrated zirconia doped with yttrium particles during CDJP was described in reference (Buinachev 2022). Dense spherical aggregates were produced at pH values of 4 and 5, whereas loose floccule-like agglomerates formed at pH values of 3, 7 and 8. The sample obtained at a pH of 6 contained both types of particles. The presence of Zr-boundedNO 3 − ions leads to a significant change in the acid‒base properties of the surface and, subsequently, a decrease in the specific surface area and pore volume, as noted in (Mashkovtsev 2023). Concurrently, the elimination of excess NO 3 − ions in conjunction with hydrothermal treatment of the hydrated zirconia slurry allows for the production of mesoporous zirconia with a high specific surface area. The acidity of a solution is one of the key factors determining the chemical form of Zr in aqueous solutions (Zhang 2024). In aqueous solutions, zirconium is present in the tetravalent form, Zr(IV), and is easily coordinated by hydroxide ions (Sasaki 2008). A decrease in acidity leads to the formation of [Zr 4 (OH) 8 (H 2 O) 16 ] 8+ (Klove 2022), octamers (Singhal 1996) and other thread-like particles (Bremholm 2015; Gossard 2014; Stawski 2012). The impact of the chemical form of Zr (IV) in aqueous solutions on the properties of Zr-containing nanostructured particles obtained via the sol-gel method has been well studied. Concurrently, analogous studies on the mechanisms of nucleation and aggregation of hydrated zirconia particles in the CDJP process, in addition to the characteristics of zirconia powders generated from these particles, have been underrepresented in the literature. This study examined the impact of the NO 3 − -to-ZrO 2+ molar ratio in a zirconium oxynitrate solution on hydrated zirconia particle nucleation and aggregation during CDJP. Additionally, the properties of the xerogels formed by drying and the zirconia powders obtained after calcination were investigated. Experimental Synthesis methods In the first stage of the hydrated zirconia synthesis, initial zirconium oxynitrate solutions with varying NO 3 - /ZrO 2+ molar ratios were prepared by dissolving of zirconium carbonate in nitric acid. The concentration of Zr was determined gravimetrically, and the solution was diluted with water to 2.5 mol/L. A series of syntheses were conducted, with preliminary heating of the initial solutions at 80 °C. A solution of ammonia at a concentration of 15 wt. % was used as the precipitant solution. The CDJP was conducted in a 5-L fluoroplastic reactor at room temperature with a stirring speed of 140 rpm, facilitated by an overhead stirrer. Prior to the precipitation process, an aqueous solution of ammonium nitrate with a concentration of 1.0 mol/L and a volume of 0.3 L was prepared in the reactor. Dropwise dosing of zirconium oxynitrate and ammonia solutions was conducted in a simultaneous manner via peristaltic pumps. The flow rate of the zirconium oxynitrate solution was 5 mL/min. The flow rate of the precipitant solution was adjusted via a pH meter connected to the peristaltic pump, with the objective of maintaining a constant pH value in the reaction zone. The CDJP was carried out for 600 minutes at a constant pH value of 4. The resulting slurry was filtered on a vacuum suction filter, subsequently dried at 50 °C to obtain xerogels, and then calcined at 900 °C for 2 hours. The samples were designated Zr-1, Zr-2, Zr-3 and Zr-4 and were obtained by using a zirconium oxynitrate solution with NO 3 - /ZrO 2+ ratios of (2), (1.8), (1.6) and (1.4), respectively. The samples obtained from the solutions preheated to 80 °C were designated Zr-1t, Zr-2t, Zr-3t and Zr- 4t. Research methods The acidity of the zirconium oxynitrate solution was detected by a «Multitest» pH meter. The particle size distribution of the samples was characterized via laser diffraction via an Analysette 22 NanoTecPlus (Fritsch). The particle size dispersion was calculated as ((d90-d10)/d50). Optical images of the slurry particles were obtained using an Olympus GX-71 microscope. Thermal analysis was carried out on an STA 449 F1 Jupiter (Netzsch) in platinum crucibles, followed byanalysis of the remaining gases on an AeoLos QMS 403C (Netzsch) mass spectrometer. The heating rate was 10 °C/min, and the temperature range was 25–1000 °С. The surface area and porosity of the samples were estimated by processing the isotherms of low-temperature adsorption‒desorption of nitrogen on a Nova Series 1200e analyzer (Quantachrome Instruments). X-ray diffractograms of the samples were obtained on an X'Pert Pro MPD diffractometer (PANanalytical B.V.) with a solid-state pixel detector under CuK α radiation using a b-filter on the secondary beam (1.5418 Å). Processing was performed via full profile Rietveld analysis via X'Pert High Score Plus software. Crystal sizes were determined via the Scherrer method using reflections at small scattering angles (shape factor K = 0.9). The surface morphology was analyzed via microphotographs via an AURIGA CrossBeam scanning electron microscope (Carl Zeiss Group). Results and discussion Effect of polymerization on hydrated zirconia nucleation and aggregation during CDJP Two series of samples were prepared from solutions with various NO 3 - /ZrO 2+ ratios. The samples prepared from unheated and heated solutions were designated the first and second series, respectively. The acidity of the prepared solutions was initially evaluated. As expected, the pH of the solutions increased with decreasing NO 3 - /ZrO 2+ ratio (Fig. 1). Notably, heating the solutions to 80 °C resulted in an increase in acidity. This provides a potential indicator of an increase in the degree of Zr (IV) polymerization in the oxynitrate solutions as a result of an increase in the depth of ZrO 2+ ion hydrolysis via the olation and oxalation processes. For the first series of samples, an increase in the average particle diameter and a decrease in dispersion were observed during CDJP (Fig. 2-a). Furthermore, a reduction in the size dispersion was observed during the initial 200 minutes of precipitation, after which the values remained relatively constant. Sample Zr-4 exhibited notable differences from the other samples in the series, characterized by the largest particle diameter and the most extensive size dispersion during CDJP. For the second series of samples (Fig. 2-b), a similar trend was observed, but the differences between the samples were more significant. The samples of Zr-2t and Zr-3t presented greater average particle diameters during CDJP than did their corresponding analogs, Zr-2 and Zr-3. The average particle diameter and size dispersion change most interestingly during CDJP for sample Zr-4t. The average particle diameter increases sharply up to 150 min of precipitation and then gradually decreases, and at the completion of precipitation, this sample is characterized by the lowest value of the average particle diameter equal to 36.1 μm. In this case, the particle size dispersion in the CDJP process increases significantly. Notably, at the macro level, in the case of the Zr-4t sample, the viscosity of the slurry increased significantly starting from the 100th minute of precipitation. This led to a deterioration in the quality of slurry mixing and a change in the hydrodynamic parameters of the process, which in turn could affect the nucleation and aggregation of hydrated zirconia particles during CDJP. Fig. 3 and S1 show the particle size distributions at different stages of precipitation. In all the cases, a precipitate with a wide monomodal particle size distribution formed during the first 10 min of CDJP. All the samples were characterized by a peak of primary particles from 0.1 to 5 μm and a peak of aggregates starting from 5 μm. It is evident that the particle evolution during precipitation of the Zr-1 and Zr-1t samples was virtually identical. However, a decrease in the NO 3 - /ZrO 2+ ratio to 1.4 led to an increase in the primary particle proportion during the overall CDJP process and a notable shift in the distribution to the region of more than 150 μm starting from 400 min of CDJP. At the same time, preheating the solution with such that NO 3 - /ZrO 2+ ratio facilitates a more pronounced increase in the proportion of primary particles. Moreover, after 400 minutes, a sharp increase in the proportion of primary particles was observed. This in turn resulted in a decrease in the average particle diameter and an increase in dispersion. The peak characterizing primary particles were subjected to further analysis via the population balance method. Fig. 4-a shows the results of the calculations in the form of distributions in the region of 1 μm at different precipitation stages for the Zr-4 and Zr-4t samples. Additionally, Fig. 4-b shows the dependence of the hydrated zirconia modal primary particle diameter on the NO 3 - /ZrO 2+ ratio in the oxynitrate solution. The data indicate that the size of the primary particles increased with decreasing NO 3 - /ZrO 2+ ratio. In addition, preheating of the solutions led to an increase in the modal diameter of the primary particle population. For the Zr-4t sample, the growth of the primary particle modal diameter was the most pronounced, and the value reached approximately 1.84 µm at the completion of CDJP. Furthermore, a notable increase in the quantity of primary particles was identified, particularly toward the conclusion of the CDJP. Notably, the number of primary particles up to 300 min CDJP was lower for the Zr-4t sample than for the Zr-4 sample. This indicates that the observed increase in slurry viscosity during CDJP for the Zr-4t sample was due to an increase in the hydration degree of the formed particles. This is in accordance with the optical images, which demonstrated that the Zr-4t sample (Fig. 5-d, e and f) was gel-like, comprising particles with indistinct boundaries. Large floccules formed at 300 minutes of CDJP, and the outer boundaries were leveled (Fig. 5-e). However, at the completion of the CDJP, the solid phase was represented by a wide range of aggregates from 5 to 25 μm (Fig. 5-f). In contrast, for the Zr-1 sample (Fig. 5-a, b and c), particles with clear boundaries were found throughout the CDJP process. By the completion of precipitation, spherical aggregates of almost the same size are formed (Fig. 5-c). Evolution of hydrated zirconia particles during drying and calcination Xerogel samples were obtained by drying the precipitate after filtration. Fig. 6 shows the mass loss and differential thermal analysis (DTA) curves for the Zr-1 sample, accompanied by plots of the variation in ionic current at selected masses (Fig. 6-b). The thermal decomposition of the xerogel samples followed a similar pattern to that observed in our previous research (Mashkovtsev 2023). The xerogels contained adsorbed water, which was removed during thermal decomposition in the I (25–250 °C) and II (250–300 °C) ranges. Moreover, the composition of the xerogels contains ammonium nitrate, which was observed to decompose within intervals II, III, and IV. During this process, nitric oxide (NO) and nitrogen dioxide (NO 2 ) are released. These compounds result from the decomposition of nitrate ions that are directly bound to zirconium (Mashkovtsev 2023). Importantly, no definitive pattern of change in the chemical composition of the xerogels was observed in relation to the nitrate ion concentration in the initial solution. Nevertheless, significant differences in the surface area and porosity of the xerogels are clearly demonstrated in Table 1. A decrease in the NO 3 - /ZrO 2+ ratio resulted in an increase in the specific surface area and pore volume and a decrease in the average pore diameter of hydrated zirconia xerogels when both unheated and preheated zirconium oxynitrate solutions were used during the CJDP. Notably, the heating of the solutions had a nonlinear influence on the specific surface area and pore volume of the xerogels. Therefore, for the Zr-1t and Zr-2t samples, notable reductions in the specific surface area and pore volume were observed. The low specific surface area and porosity of these samples can be attributed to the coalescence of hydrated zirconia particles during the drying process, which was caused by the formation of excess nitric acid as a result of olation and oxolation processes. Conversely, the specific surface area and pore volume of the Zr-3t and Zr-4t samples were greater than those of their respective analogs. Table 1 - Surface and porosity parameters of the xerogel samples Sample Surface area, m/g 2 Pore volume, cm/g 3 Pore diameter, nm Micropore volume proportion, % Zr-1 115 0,06 2,1 75 Zr-2 110 0,06 2,1 78 Zr-3 150 0,08 2,0 65 Zr-4 210 0,11 2,0 43 Zr-1t 24 0,02 2,9 12 Zr-2t 30 0,02 2,4 1 Zr-3t 240 0,13 2,2 - Zr-4t 230 0,13 2,2 - The evolution of hydrated zirconia particles during drying and calcination for all samples, with the exception of Zr-4t, followed a pattern that was analogous to that observed in sample Zr-1 (Fig. 7-a). During drying and calcination, the average particle diameter decreases, as evidenced by the shift in the particle size distribution to the region of smaller values, whereas the size dispersion remains virtually unchanged. The aggregation process of sample Zr-4t during drying and calcination differed from that of the other samples (Fig. 7-b). At the completion of precipitation, a wide bimodal particle size distribution with peaks in the regions of 5 and 50 μm was observed. After drying, the peak in the region of 5 μm decreases, and the distribution shifts to the region of higher values. After calcination, a peak of large agglomerates larger than 100 μm appears, indicating adhesion of the particle fraction during calcination. Interestingly, for the series of samples synthesized from unheated solutions, the decrease in particle diameter after drying and calcination occurred linearly (Fig. 7-c), whereas for the series of samples obtained from heated solutions, the decrease in particle diameter after drying occurred sharply (Fig. 7-d). This indicates a greater degree of hydration of the hydrated zirconia samples obtained using preheated zirconium oxynitrate solutions. The morphology of both series of samples after calcination differed significantly (Fig. 8). For example, the Zr-1 sample was characterized by agglomerates with clear boundaries of primary particles (Fig. 8-a, 9-a). In contrast, the Zr-4t sample presented dense aggregates with smooth surfaces, minor inclusions, and microcracks following calcination (Fig. 8-b, 9-b). This suggests a greater degree of shrinkage during calcination and a reduced aggregates porosity. The porosities of all the samples were evaluated by scanning electron microscopy (SEM) images with «ImageJ» software. The results of this evaluation are presented in Fig. 9-с. With a decrease in the NO 3 - /ZrO 2+ ratio, the particles became denser, and heating the solution before CDJP enhanced this effect. As shown in the diffraction patterns (Fig. 10-a, S2), well-crystallized ZrO 2 with monoclinic modification was observed in all the calcined samples. A decrease in the NO 3 - /ZrO 2+ ratio contributed to a decrease in the crystallite size, as evidenced by the broadening of the diffraction reflections. Furthermore, preliminary heating of the solutions clearly enhances the observed changes in the structure. Notably, the Zr-4t sample exhibited the lowest degree of crystallinity, with a crystallite size of approximately 24 nm. Hydrated zirconia particle nucleation and aggregation mechanism In this study, a series of experiments involving varying the NO 3 - /ZrO 2+ ratio and heating at the stage of zirconium oxynitrate solution preparation were conducted. A decrease in the NO 3 - /ZrO 2+ ratio, as well as heating, leads to an increase in the degree of Zr (IV) polymerization. The average diameter of primary and secondary particles of hydrated zirconia in slurries during CDJP, as well as xerogels obtained after drying and zirconia powders formed after calcination, was estimated via the laser diffraction method. An increase in the degree of Zr(IV) polymerization leads to an increase in the average diameter of secondary aggregates of hydrated zirconia, as well as the size of primary particles. Conversely, a decrease in the crystallite size was also determined via the XRD method. The specific surface area and porosity of the xerogels, which were determined by low-temperature nitrogen adsorption desorption, increased, and the porosity of the calcined powders, according to the SEM images, decreased with increasing degree of Zr (IV) polymerization. It has been demonstrated that the preliminary heating of solutions leads to an increase in the detected effects. The Zr-4t sample exhibited distinctive features of particle evolution during CDJP, which were not observed in the other samples. This was associated with an increase in slurry viscosity during precipitation, resulting in altered nucleation and aggregation conditions during CDJP, drying, and subsequent calcination. The initial stage of hydrolysis in a zirconium oxynitrate solution initiates the polymerization and polycondensation of hydrated zirconia. Given the elevated degree of supersaturation, the rate of processes is considerable. Consequently, polycondensation of hydrated zirconia are the prevailing phenomenon. At this stage, prenucleation clusters and nuclei of hydrated zirconia are formed, with sizes that, in accordance with the prevailing model concepts, do not exceed 5 nm. Owing to the high surface energy of the nuclei and their high concentration, along with the formation of nuclei, their spontaneous agglomeration processes occur with the formation of primary particles with a size at the micron scale. Primary particles, in turn, undergo subsequent agglomeration with the formation of secondary agglomerates or floccules with a tens of microns. It can be hypothesized that the reduction in the NO 3 - /ZrO 2+ ratio and the heating of the zirconium oxynitrate solution result in an increase in the length of the polymer chains composed of Zr 4 (OH) 8 (NO 3 ) 8 tetramers (Fig. 11). During hydrolysis of such polymerized solutions, the terminal nitrate ions are replaced by hydroxyl ions, accompanied by spontaneous cross-linking or polycondensation of the chains with the formation of nuclei. An increase in the length of the polymer chains in the solution results in the formation of looser, less densely packed prenucleation clusters and nuclei with greater boundary roughness. The voids that are formed during the crosslinking of polymer chains are filled with a solvent, which increases the degree of hydration of the particles. The blurring of particle boundaries in optical images, an increase in the viscosity of slurries and a change in the nature of moisture removal from samples during heat treatment support this phenomenon. The high hydration and roughness of the nuclei and the primary particles present determine the formation of dense smooth secondary particles with significantly lower macroporosity during heat treatment. The removal of moisture from the voids formed during the polycondensation of long polymer chains results in the formation of mesoporous, which determine the large specific surface area of the particles and prevent the formation of large crystals during firing. Notably, the formation of excessively dense aggregates might result in their destruction during calcination. Thus, the regulation of zirconium polynuclear hydroxo complex polymer chains length allows control of the roughness and porosity of zirconia powders obtained via the CDJP method. This can be useful in the production of powders for gas-thermal spraying. Conclusions The CDJP method allows hydrated zirconia particles and zirconia powders with different sizes, morphologies, and structures to be obtained by varying the degree of Zr(IV) polymerization in the initial solution. A mechanism for the aggregation of particles obtained via the CDJP method from solutions with different degrees of polymerization was proposed. 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Adv Powder Tech 25, 490 – 494. https://doi.org/10.1016/j.apt.2013.08.001 Xi X, Abe H, Kuruma K, Harada R, Shui A, Naito M (2014) Novel Co-precipitation method to synthesize NiO-YSZ nanocomposite powder for solid oxide fuel cell. Adv Powder Tech 25(2) 490 – 494. https://doi.org/10.1016/j.apt.2013.08.001 Yaon H, Jia D, Zhang H (2015) A new approach of fabricating monodisperse micrometer hollow zirconia spheres. Ceram Int 41, 1531 – 1534. https://doi.org/10.1016/j.ceramint.2014.09.088 Yue W, Li Y, Zheng Y, Wu T, Zhao Ch, Zhao J (2019) Enhancing coking resistance of Ni/YSZ electrodes: in situ characterisation, mechanism research, and surface engineering. Nano Energy 62, 64 – 78. https://doi.org/10.1016/j.nanoen.2019.05.006 Zhang Z, Duan W, Cheng X, Chen J, Wan J, Sun T (2024) Evolution of the chemical form of zirconium in aqueous solution during denitration and its influence on extraction by TRPO. Sep and Pur Tech 329:125157. https://doi.org/10.1016/j.seppur.2023.125157 Supplementary Files SupplementaryMaterials.docx Cite Share Download PDF Status: Published Journal Publication published 01 Jul, 2025 Read the published version in Chemical Papers → Version 1 posted Reviewers agreed at journal 22 Mar, 2025 Reviewers invited by journal 22 Mar, 2025 Editor invited by journal 09 Mar, 2025 Editor assigned by journal 08 Mar, 2025 First submitted to journal 06 Mar, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6175824","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":432522721,"identity":"67e92d14-6e81-4733-9783-a9e21efc5d9c","order_by":0,"name":"Maksim Mashkovtsev","email":"","orcid":"","institution":"IHTE UB RAS: Institut vysokotemperaturnoj elektrohimii Ural'skogo otdelenia Rossijskoj akademii nauk","correspondingAuthor":false,"prefix":"","firstName":"Maksim","middleName":"","lastName":"Mashkovtsev","suffix":""},{"id":432522722,"identity":"5002f4e8-cef5-4659-89da-7ff299ae04b9","order_by":1,"name":"Evgenie Baksheev","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA00lEQVRIie3PsQrCMBCA4ZOCLme7JiD6CpGCIoi+SkXopINPYEGoS93jW9QnMHKDS90VHCqCu7goFLSzg2k3h/zTBe7jCIDJ9JchVAJQ+WApKkuqHoFXjqCwChEH6ru7zM5Nh03uNHv2oSs1jgf2mG/Cm8vlNCbp+dA4aohQKPgloFGcHGLC/DuMachQoftKM5pvkyTNyVtPBGCHx1XyRC2CnCg9YWT7vXVIbbkPBaE/Robpb+IsV3SKMmo5C+v6wP6gyWqaK2B9vVGzbzKZTKYifQClzkUWetfOaAAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0003-2851-1294","institution":"IHTE UB RAS: Institut vysokotemperaturnoj elektrohimii Ural'skogo otdelenia Rossijskoj akademii nauk","correspondingAuthor":true,"prefix":"","firstName":"Evgenie","middleName":"","lastName":"Baksheev","suffix":""},{"id":432522723,"identity":"540233c5-8b06-4315-a078-335d8d996d87","order_by":2,"name":"Maksim Domashenkov","email":"","orcid":"","institution":"IHTE UB RAS: Institut vysokotemperaturnoj elektrohimii Ural'skogo otdelenia Rossijskoj akademii nauk","correspondingAuthor":false,"prefix":"","firstName":"Maksim","middleName":"","lastName":"Domashenkov","suffix":""},{"id":432522724,"identity":"1b02f8af-55d8-478e-aa50-9cf115a0fd0e","order_by":3,"name":"Denis Khionin","email":"","orcid":"","institution":"IHTE UB RAS: Institut vysokotemperaturnoj elektrohimii Ural'skogo otdelenia Rossijskoj akademii nauk","correspondingAuthor":false,"prefix":"","firstName":"Denis","middleName":"","lastName":"Khionin","suffix":""},{"id":432522725,"identity":"338d78e9-04db-4e18-a900-310867f9247a","order_by":4,"name":"Nickolay Borodin","email":"","orcid":"","institution":"IHTE UB RAS: Institut vysokotemperaturnoj elektrohimii Ural'skogo otdelenia Rossijskoj akademii nauk","correspondingAuthor":false,"prefix":"","firstName":"Nickolay","middleName":"","lastName":"Borodin","suffix":""},{"id":432522726,"identity":"233fbca7-16b4-49b8-a26d-4cbde8699870","order_by":5,"name":"Dmitry Polivoda","email":"","orcid":"","institution":"IHTE UB RAS: Institut vysokotemperaturnoj elektrohimii Ural'skogo otdelenia Rossijskoj akademii nauk","correspondingAuthor":false,"prefix":"","firstName":"Dmitry","middleName":"","lastName":"Polivoda","suffix":""},{"id":432522727,"identity":"3d121787-a55f-40fc-86e9-3708e4b01e20","order_by":6,"name":"Vitaliy Noskov","email":"","orcid":"","institution":"IHTE UB RAS: Institut vysokotemperaturnoj elektrohimii Ural'skogo otdelenia Rossijskoj akademii nauk","correspondingAuthor":false,"prefix":"","firstName":"Vitaliy","middleName":"","lastName":"Noskov","suffix":""}],"badges":[],"createdAt":"2025-03-07 07:13:48","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6175824/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6175824/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11696-025-04160-y","type":"published","date":"2025-07-01T15:56:52+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":79590627,"identity":"0a040750-d7ac-4766-bb69-a9cba1d1c982","added_by":"auto","created_at":"2025-03-31 13:07:54","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":5738,"visible":true,"origin":"","legend":"\u003cp\u003epH values of initial zirconium oxynitrate solutions.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/683dbb9e2cfc74f1364f725f.png"},{"id":79590628,"identity":"fd294b1e-fd05-4062-9479-62c9fa5b69f7","added_by":"auto","created_at":"2025-03-31 13:07:54","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":194501,"visible":true,"origin":"","legend":"\u003cp\u003eDependence of theaverage diameter (upper) and size dispersion (lower) of the particles on the CDJP duration for the first (a) and second (b) series of samples: Zr-1 and Zr-1t (1), Zr-2 and Zr-2t (2), Zr-3 and Zr-3t (3) and Zr- 4 and Zr-4t (4).\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/06bdf7dd68e0a440e3486dc1.png"},{"id":79590631,"identity":"8d6cde4a-e943-4cfb-9fd7-12c750d6ef13","added_by":"auto","created_at":"2025-03-31 13:07:54","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":223548,"visible":true,"origin":"","legend":"\u003cp\u003eParticle size distributions at different CDJP stages for samples: a - Zr-1, b - Zr-4, c - Zr-1t and d - Zr-4t.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/c3b03ab1917fb95022036b33.png"},{"id":79591536,"identity":"43e61aec-4482-43c5-822b-ccb0e4984185","added_by":"auto","created_at":"2025-03-31 13:15:54","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":108903,"visible":true,"origin":"","legend":"\u003cp\u003eResults of processing the particle size distributions via the population balance method: a - number of particle distributions in the peak area of the primary particles for the Zr-4 and Zr-4t samples; b - dependence of the modal diameter of the primary particles on the\u003cbr\u003e\nNO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+ \u003c/sup\u003eratio.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/fc5b9f3840ac5357aed60963.png"},{"id":79590633,"identity":"43a35134-f2d6-49f0-b1e5-46ed2d612965","added_by":"auto","created_at":"2025-03-31 13:07:54","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":535384,"visible":true,"origin":"","legend":"\u003cp\u003eOptical images of hydrated zirconia particles of the Zr-1 sample (upper) and Zr-4t sample (lower) at different CDJP stages: a, d - 30 min, b, e - 300 min, c, f - 600 min.\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/1e68fe09d5554dd42e5260e7.png"},{"id":79590637,"identity":"b8cc78a9-dfeb-4e2a-a1e7-4094583b0ede","added_by":"auto","created_at":"2025-03-31 13:07:54","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":121244,"visible":true,"origin":"","legend":"\u003cp\u003eTG and SDTA curves for sample Zr-1 (a); graphs of ion currents for H\u003csub\u003e2\u003c/sub\u003eO, N\u003csub\u003e2\u003c/sub\u003eO, NO and NO\u003csub\u003e2\u003c/sub\u003e for sample Zr-1 (b).\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/d315ad221e74efd05a09611d.png"},{"id":79590636,"identity":"cda119bc-a0f9-4bca-8911-a30598242e5f","added_by":"auto","created_at":"2025-03-31 13:07:54","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":150973,"visible":true,"origin":"","legend":"\u003cp\u003eParticle size evolution: a - PSD for Zr-1; b - PSD for Zr-4t; c - diameter of particles obtained from an unheated solution; d - diameter of particles obtained from a heated solution.\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/66c0ef95e33226fe7f5112e6.png"},{"id":79590634,"identity":"e0a9747f-7fe8-40d5-85e3-44f8def79c5d","added_by":"auto","created_at":"2025-03-31 13:07:54","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":347686,"visible":true,"origin":"","legend":"\u003cp\u003eSEM images of the calcined samples: a- Zr-1 (50x), b- Zr-4t (50x).\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/2764e8aed923d0e9827da673.png"},{"id":79591539,"identity":"2fc6fa91-76c1-469a-8c5c-dddb2a9cfc8a","added_by":"auto","created_at":"2025-03-31 13:15:54","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":542850,"visible":true,"origin":"","legend":"\u003cp\u003eSEM images of calcined samples: a - Zr-1 (10 000x); b - Zr-3t (10 000x); с \u0026nbsp;- particle porosity calculated from SEM images.\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/80747f32a478df73993a2762.png"},{"id":79592423,"identity":"c622ad40-7ad4-4dbb-8fe0-b78a5fa2f2c0","added_by":"auto","created_at":"2025-03-31 13:23:54","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":95671,"visible":true,"origin":"","legend":"\u003cp\u003eXRD results for samples after calcination: a - XRD pattern for the Zr-4 and Zr-4t samples; b - crystal size.\u003c/p\u003e","description":"","filename":"floatimage10.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/9fc9442956953380484599cb.png"},{"id":79591541,"identity":"09089b13-5152-48d8-8d24-d9749771e7c1","added_by":"auto","created_at":"2025-03-31 13:15:54","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":305958,"visible":true,"origin":"","legend":"\u003cp\u003eMechanism of hydrated zirconia particle nucleation and aggregation.\u003c/p\u003e","description":"","filename":"floatimage11.png","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/96da274a0a41c69f81f82592.png"},{"id":86178854,"identity":"346be0b8-c096-4b4c-b860-15d65a24a577","added_by":"auto","created_at":"2025-07-07 16:01:07","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3341409,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/9b85aeef-15ee-468d-9968-71e3e74a4627.pdf"},{"id":79591537,"identity":"1985c954-0cec-4783-9fd6-2a770f84a1eb","added_by":"auto","created_at":"2025-03-31 13:15:54","extension":"docx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":1302133,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryMaterials.docx","url":"https://assets-eu.researchsquare.com/files/rs-6175824/v1/325f628f6cc7ab27e2cf1df0.docx"}],"financialInterests":"","formattedTitle":"\u003cp\u003ePolymerization of Zr (IV) in an oxynitrate solution: effects on the nucleation and aggregation of hydrated ZrO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eZirconia is a material with a wide range of applications in modern industry. These include use as a support in catalysts, biocompatible ceramics in dentistry and orthopedics (Gali 2018; Catauro 2019; Pandey 2014), electrodes and high-temperature electrochemical devices with electrolytes (Xi 2014; Prakash 2014; Yue 2019; Xi 2014), and many other areas. The key characteristics of zirconia powders are particle size, shape and dispersibility. Currently, various methods are used to synthesize zirconia powders with controlled properties: the emulsion method (Liu 2019; Shi 2020), sol-gel method (Widoniak 2005; Widoniak 2005; Liang 2020; Yaon 2015; Uchiyama 2012), hydrothermal (Agamy 2023) and spray-drying method (Pan 2011; Kim 2007; Garcia 2011; Chen 2021). These methods facilitate the production of zirconia powders with a regular particle shape and size, ranging from a few to hundreds of micrometers. However, the aforementioned methods are typically quite complex and labor intensive, which increases the cost of narrowly dispersed zirconia powder and constrains its applicability.\u003c/p\u003e \u003cp\u003eThe controlled double-jet precipitation (CDJP) method is widely used for a wide range of powder species synthesis, particularly the ZrO\u003csub\u003e2\u003c/sub\u003e. This method enables precise control of the synthesis conditions, including the pH value, degree of supersaturation, and rate of reagent introduction into the reaction medium. Accordingly, the CDJP method is considered the most effective in terms of regulating the key properties of powder materials, including dispersibility, morphology and phase composition (Stavek 1992; Chen 2019; Stavek 1990). The CDJP process involves the nucleation of primary particles and their subsequent growth through the Ostwald ripening mechanism, in addition to layer-by-layer aggregation of unstable colloidal particles (Stavek 1992).\u003c/p\u003e \u003cp\u003eThe influence of CDJP conditions on the nucleation and aggregation of hydrated zirconia and on the properties of zirconia powder has been well studied in our previous studies. In (Buinachev 2021), the phenomenon of layer-by-layer aggregation of hydrated zirconia particles was detected and interpreted, allowing the preparation of monodisperse zirconia powders in a narrow pH range. The effect of pH precipitation on the aggregation mechanism of hydrated zirconia doped with yttrium particles during CDJP was described in reference (Buinachev 2022). Dense spherical aggregates were produced at pH values of 4 and 5, whereas loose floccule-like agglomerates formed at pH values of 3, 7 and 8. The sample obtained at a pH of 6 contained both types of particles. The presence of Zr-boundedNO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e ions leads to a significant change in the acid‒base properties of the surface and, subsequently, a decrease in the specific surface area and pore volume, as noted in (Mashkovtsev 2023). Concurrently, the elimination of excess NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e ions in conjunction with hydrothermal treatment of the hydrated zirconia slurry allows for the production of mesoporous zirconia with a high specific surface area.\u003c/p\u003e \u003cp\u003eThe acidity of a solution is one of the key factors determining the chemical form of Zr in aqueous solutions (Zhang 2024). In aqueous solutions, zirconium is present in the tetravalent form, Zr(IV), and is easily coordinated by hydroxide ions (Sasaki 2008). A decrease in acidity leads to the formation of [Zr\u003csub\u003e4\u003c/sub\u003e(OH)\u003csub\u003e8\u003c/sub\u003e(H\u003csub\u003e2\u003c/sub\u003eO)\u003csub\u003e16\u003c/sub\u003e]\u003csup\u003e8+\u003c/sup\u003e (Klove 2022), octamers (Singhal 1996) and other thread-like particles (Bremholm 2015; Gossard 2014; Stawski 2012). The impact of the chemical form of Zr (IV) in aqueous solutions on the properties of Zr-containing nanostructured particles obtained via the sol-gel method has been well studied. Concurrently, analogous studies on the mechanisms of nucleation and aggregation of hydrated zirconia particles in the CDJP process, in addition to the characteristics of zirconia powders generated from these particles, have been underrepresented in the literature. This study examined the impact of the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e-to-ZrO\u003csup\u003e2+\u003c/sup\u003e molar ratio in a zirconium oxynitrate solution on hydrated zirconia particle nucleation and aggregation during CDJP. Additionally, the properties of the xerogels formed by drying and the zirconia powders obtained after calcination were investigated.\u003c/p\u003e"},{"header":"Experimental","content":"\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSynthesis methods\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the first stage of the hydrated zirconia synthesis, initial zirconium oxynitrate solutions with varying NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e molar ratios were prepared by dissolving of zirconium carbonate in nitric acid. The concentration of Zr was determined gravimetrically, and the solution was diluted with water to 2.5 mol/L. A series of syntheses were conducted, with preliminary heating of the initial solutions at 80 \u0026deg;C. A solution of ammonia at a concentration of 15 wt. % was used as the precipitant solution. The CDJP was conducted in a 5-L fluoroplastic reactor at room temperature with a stirring speed of 140 rpm, facilitated by an overhead stirrer. Prior to the precipitation process, an aqueous solution of ammonium nitrate with a concentration of 1.0 mol/L and a volume of 0.3 L was prepared in the reactor. Dropwise dosing of zirconium oxynitrate and ammonia solutions was conducted in a simultaneous manner via peristaltic pumps. The flow rate of the zirconium oxynitrate solution was 5 mL/min. The flow rate of the precipitant solution was adjusted via a pH meter connected to the peristaltic pump, with the objective of maintaining a constant pH value in the reaction zone. The CDJP was carried out for 600 minutes at a constant pH value of 4. The resulting slurry was filtered on a vacuum suction filter, subsequently dried at 50 \u0026deg;C to obtain xerogels, and then calcined at 900 \u0026deg;C for 2 hours. The samples were designated Zr-1, Zr-2, Zr-3 and Zr-4 and were obtained by using a zirconium oxynitrate solution with NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratios of (2), (1.8), (1.6) and (1.4), respectively. The samples obtained from the solutions preheated to 80\u003csup\u003e\u0026nbsp;\u003c/sup\u003e\u0026deg;C were designated Zr-1t, Zr-2t, Zr-3t and Zr- 4t.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eResearch methods\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe acidity of the zirconium oxynitrate solution was detected by a \u0026laquo;Multitest\u0026raquo;\u0026nbsp;pH meter. The particle size distribution of the samples was characterized via laser diffraction via an Analysette 22 NanoTecPlus (Fritsch). The particle size dispersion was calculated as ((d90-d10)/d50). Optical images of the slurry particles were obtained using an Olympus GX-71 microscope. Thermal analysis was carried out on an STA 449 F1 Jupiter (Netzsch) in platinum crucibles, followed byanalysis of the remaining gases on an AeoLos QMS 403C (Netzsch) mass spectrometer. The heating rate was 10 \u0026deg;C/min, and the temperature range was 25\u0026ndash;1000 \u0026deg;С. The surface area and porosity of the samples were estimated by processing the isotherms of low-temperature adsorption‒desorption of nitrogen on a Nova Series 1200e analyzer (Quantachrome Instruments). X-ray diffractograms of the samples were obtained on an X\u0026apos;Pert Pro MPD diffractometer (PANanalytical B.V.) with a solid-state pixel detector under CuK\u003csub\u003e\u0026alpha;\u003c/sub\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003eradiation using a b-filter on the secondary beam (1.5418 \u0026Aring;). Processing was performed via full profile Rietveld analysis via X\u0026apos;Pert High Score Plus software. Crystal sizes were determined via the Scherrer method using reflections at small scattering angles (shape factor K = 0.9). The surface morphology was analyzed via microphotographs via an AURIGA CrossBeam scanning electron microscope (Carl Zeiss Group).\u003c/p\u003e"},{"header":"Results and discussion","content":"\u003cp\u003e\u003cstrong\u003e\u003cem\u003eEffect of polymerization on hydrated zirconia nucleation and aggregation during CDJP\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTwo series of samples were prepared from solutions with various NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratios. The samples prepared from unheated and heated solutions were designated the first and second series, respectively. The acidity of the prepared solutions was initially evaluated. As expected, the pH of the solutions increased with decreasing NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e /ZrO\u003csup\u003e2+\u003c/sup\u003e ratio (Fig. 1). Notably, heating the solutions to 80 \u0026deg;C resulted in an increase in acidity. This provides a potential indicator of an increase in the degree of Zr (IV) polymerization in the oxynitrate solutions as a result of an increase in the depth of ZrO\u003csup\u003e2+\u003c/sup\u003e ion hydrolysis via the olation and oxalation processes.\u003c/p\u003e\n\u003cp\u003eFor the first series of samples, an increase in the average particle diameter and a decrease in dispersion were observed during CDJP (Fig. 2-a). Furthermore, a reduction in the size dispersion was observed during the initial 200 minutes of precipitation, after which the values remained relatively constant. Sample Zr-4 exhibited notable differences from the other samples in the series, characterized by the largest particle diameter and the most extensive size dispersion during CDJP. For the second series of samples (Fig. 2-b), a similar trend was observed, but the differences between the samples were more significant. The samples of Zr-2t and Zr-3t presented greater average particle diameters during CDJP than did their corresponding analogs, Zr-2 and Zr-3. The average particle diameter and size dispersion change most interestingly during CDJP for sample Zr-4t. The average particle diameter increases sharply up to 150 min of precipitation and then gradually decreases, and at the completion of precipitation, this sample is characterized by the lowest value of the average particle diameter equal to 36.1 \u0026mu;m. In this case, the particle size dispersion in the CDJP process increases significantly. Notably, at the macro level, in the case of the Zr-4t sample, the viscosity of the slurry increased significantly starting from the 100th minute of precipitation. This led to a deterioration in the quality of slurry mixing and a change in the hydrodynamic parameters of the process, which in turn could affect the nucleation and aggregation of hydrated zirconia particles during CDJP.\u003c/p\u003e\n\u003cp\u003eFig. 3 and S1 show the particle size distributions at different stages of precipitation. In all the cases, a precipitate with a wide monomodal particle size distribution formed during the first 10 min of CDJP. All the samples were characterized by a peak of primary particles from 0.1 to 5 \u0026mu;m and a peak of aggregates starting from 5 \u0026mu;m. It is evident that the particle evolution during precipitation of the Zr-1 and Zr-1t samples was virtually identical. However, a decrease in the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio to 1.4 led to an increase in the primary particle proportion during the overall CDJP process and a notable shift in the distribution to the region of more than 150 \u0026mu;m starting from 400 min of CDJP. At the same time, preheating the solution with such that NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio facilitates a more pronounced increase in the proportion of primary particles. Moreover, after 400 minutes, a sharp increase in the proportion of primary particles was observed. This in turn resulted in a decrease in the average particle diameter and an increase in dispersion.\u003c/p\u003e\n\u003cp\u003eThe peak characterizing primary particles were subjected to further analysis via the population balance method. Fig. 4-a shows the results of the calculations in the form of distributions in the region of 1 \u0026mu;m at different precipitation stages for the Zr-4 and Zr-4t samples. Additionally, Fig. 4-b shows the dependence of the hydrated zirconia modal primary particle diameter on the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio in the oxynitrate solution. The data indicate that the size of the primary particles increased with decreasing NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio. In addition, preheating of the solutions led to an increase in the modal diameter of the primary particle population. For the Zr-4t sample, the growth of the primary particle modal diameter was the most pronounced, and the value reached approximately 1.84 \u0026micro;m at the completion of CDJP. Furthermore, a notable increase in the quantity of primary particles was identified, particularly toward the conclusion of the CDJP.\u003c/p\u003e\n\u003cp\u003eNotably, the number of primary particles up to 300 min CDJP was lower for the Zr-4t sample than for the Zr-4 sample. This indicates that the observed increase in slurry viscosity during CDJP for the Zr-4t sample was due to an increase in the hydration degree of the formed particles.\u003c/p\u003e\n\u003cp\u003eThis is in accordance with the optical images, which demonstrated that the\u0026nbsp;\u003cbr\u003e\u0026nbsp;Zr-4t sample (Fig. 5-d, e and f) was gel-like, comprising particles with indistinct boundaries. Large floccules formed at 300 minutes of CDJP, and the outer boundaries were leveled\u0026nbsp;\u003cbr\u003e\u0026nbsp;(Fig. 5-e). However, at the completion of the CDJP, the solid phase was represented by a wide range of aggregates from 5 to 25 \u0026mu;m (Fig. 5-f). In contrast, for the Zr-1 sample (Fig. 5-a, b and c), particles with clear boundaries were found throughout the CDJP process. By the completion of precipitation, spherical aggregates of almost the same size are formed (Fig. 5-c).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eEvolution of hydrated zirconia particles during drying and calcination\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eXerogel samples were obtained by drying the precipitate after filtration. Fig.\u0026nbsp;6 shows the mass loss and differential thermal analysis (DTA) curves for the Zr-1 sample, accompanied by plots of the variation in ionic current at selected masses (Fig. 6-b). The thermal decomposition of the xerogel samples followed a similar pattern to that observed in our previous research (Mashkovtsev 2023). The xerogels contained adsorbed water, which was removed during thermal decomposition in the\u0026nbsp;I (25\u0026ndash;250 \u0026deg;C) and II (250\u0026ndash;300 \u0026deg;C) ranges. Moreover, the composition of the xerogels contains ammonium nitrate, which was observed to decompose within intervals II, III, and IV. During this process, nitric oxide (NO) and nitrogen dioxide (NO\u003csub\u003e2\u003c/sub\u003e) are released. These compounds result from the decomposition of nitrate ions that are directly bound to zirconium (Mashkovtsev 2023).\u003c/p\u003e\n\u003cp\u003eImportantly, no definitive pattern of change in the chemical composition of the xerogels was observed in relation to the nitrate ion concentration in the initial solution. Nevertheless, significant differences in the surface area and porosity of the xerogels are clearly demonstrated in Table 1. A decrease in the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio resulted in an increase in the specific surface area and pore volume and a decrease in the average pore diameter of hydrated zirconia xerogels when both unheated and preheated zirconium oxynitrate solutions were used during the CJDP. Notably, the heating of the solutions had a nonlinear influence on the specific surface area and pore volume of the xerogels. Therefore, for the Zr-1t and Zr-2t samples, notable reductions in the specific surface area and pore volume were observed. The low specific surface area and porosity of these samples can be attributed to the coalescence of hydrated zirconia particles during the drying process, which was caused by the formation of excess nitric acid as a result of olation and oxolation processes. Conversely, the specific surface area and pore volume of the Zr-3t and Zr-4t samples were greater than those of their respective analogs.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1\u003c/strong\u003e \u003cem\u003e-\u0026nbsp;\u003c/em\u003eSurface and porosity parameters of the xerogel samples\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eSample\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eSurface area,\u003c/p\u003e\n \u003cp\u003em/g\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003ePore volume,\u003c/p\u003e\n \u003cp\u003ecm/g\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003ePore diameter,\u003c/p\u003e\n \u003cp\u003enm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003eMicropore volume proportion, %\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e115\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e75\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e110\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e150\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e210\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-1t\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-2t\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-3t\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e240\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003eZr-4t\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e230\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e0,13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2,2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe evolution of hydrated zirconia particles during drying and calcination for all samples, with the exception of Zr-4t, followed a pattern that was analogous to that observed in sample Zr-1 (Fig. 7-a). During drying and calcination, the average particle diameter decreases, as evidenced by the shift in the particle size distribution to the region of smaller values, whereas the size dispersion remains virtually unchanged. The aggregation process of sample Zr-4t during drying and calcination differed from that of the other samples (Fig. 7-b). At the completion of precipitation, a wide bimodal particle size distribution with peaks in the regions of 5 and 50 \u0026mu;m was observed. After drying, the peak in the region of 5 \u0026mu;m decreases, and the distribution shifts to the region of higher values. After calcination, a peak of large agglomerates larger than 100 \u0026mu;m appears, indicating adhesion of the particle fraction during calcination. Interestingly, for the series of samples synthesized from unheated solutions, the decrease in particle diameter after drying and calcination occurred linearly (Fig. 7-c), whereas for the series of samples obtained from heated solutions, the decrease in particle diameter after drying occurred sharply (Fig. 7-d). This indicates a greater degree of hydration of the hydrated zirconia samples obtained using preheated zirconium oxynitrate solutions.\u003c/p\u003e\n\u003cp\u003eThe morphology of both series of samples after calcination differed significantly (Fig. 8). For example, the Zr-1 sample was characterized by agglomerates with clear boundaries of primary particles (Fig. 8-a, 9-a). In contrast, the Zr-4t sample presented dense aggregates with smooth surfaces, minor inclusions, and microcracks following calcination (Fig. 8-b, 9-b). This suggests a greater degree of shrinkage during calcination and a reduced aggregates porosity.\u003c/p\u003e\n\u003cp\u003eThe porosities of all the samples were evaluated by scanning electron microscopy (SEM) images with \u0026laquo;ImageJ\u0026raquo; software. The results of this evaluation are presented in Fig. 9-с. With a decrease in the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio, the particles became denser, and heating the solution before CDJP enhanced this effect.\u003c/p\u003e\n\u003cp\u003eAs shown in the diffraction patterns (Fig. 10-a, S2), well-crystallized ZrO\u003csub\u003e2\u003c/sub\u003e with monoclinic modification was observed in all the calcined samples. A decrease in the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio contributed to a decrease in the crystallite size, as evidenced by the broadening of the diffraction reflections. Furthermore, preliminary heating of the solutions clearly enhances the observed changes in the structure. Notably, the Zr-4t sample exhibited the lowest degree of crystallinity, with a crystallite size of approximately 24 nm.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eHydrated zirconia particle nucleation and aggregation mechanism\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn this study, a series of experiments involving varying the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio and heating at the stage of zirconium oxynitrate solution preparation were conducted. A decrease in the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio, as well as heating, leads to an increase in the degree of Zr (IV) polymerization. The average diameter of primary and secondary particles of hydrated zirconia in slurries during CDJP, as well as xerogels obtained after drying and zirconia powders formed after calcination, was estimated via the laser diffraction method. An increase in the degree of Zr(IV) polymerization leads to an increase in the average diameter of secondary aggregates of hydrated zirconia, as well as the size of primary particles. Conversely, a decrease in the crystallite size was also determined via the XRD method. The specific surface area and porosity of the xerogels, which were determined by low-temperature nitrogen adsorption desorption, increased, and the porosity of the calcined powders, according to the SEM images, decreased with increasing degree of Zr (IV) polymerization. It has been demonstrated that the preliminary heating of solutions leads to an increase in the detected effects. The Zr-4t sample exhibited distinctive features of particle evolution during CDJP, which were not observed in the other samples. This was associated with an increase in slurry viscosity during precipitation, resulting in altered nucleation and aggregation conditions during CDJP, drying, and subsequent calcination.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp;The initial stage of hydrolysis in a zirconium oxynitrate solution initiates the polymerization and polycondensation of hydrated zirconia. Given the elevated degree of supersaturation, the rate of processes is considerable. Consequently, polycondensation of hydrated zirconia are the prevailing phenomenon. At this stage, prenucleation clusters and nuclei of hydrated zirconia are formed, with sizes that, in accordance with the prevailing model concepts, do not exceed 5 nm. Owing to the high surface energy of the nuclei and their high concentration, along with the formation of nuclei, their spontaneous agglomeration processes occur with the formation of primary particles with a size at the micron scale. Primary particles, in turn, undergo subsequent agglomeration with the formation of secondary agglomerates or floccules with a tens of microns.\u003c/p\u003e\n\u003cp\u003eIt can be hypothesized that the reduction in the NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e/ZrO\u003csup\u003e2+\u003c/sup\u003e ratio and the heating of the zirconium oxynitrate solution result in an increase in the length of the polymer chains composed of Zr\u003csub\u003e4\u003c/sub\u003e(OH)\u003csub\u003e8\u003c/sub\u003e(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e8\u003c/sub\u003e tetramers (Fig. 11). During hydrolysis of such polymerized solutions, the terminal nitrate ions are replaced by hydroxyl ions, accompanied by spontaneous cross-linking or polycondensation of the chains with the formation of nuclei. An increase in the length of the polymer chains in the solution results in the formation of looser, less densely packed prenucleation clusters and nuclei with greater boundary roughness. The voids that are formed during the crosslinking of polymer chains are filled with a solvent, which increases the degree of hydration of the particles. The blurring of particle boundaries in optical images, an increase in the viscosity of slurries and a change in the nature of moisture removal from samples during heat treatment support this phenomenon. The high hydration and roughness of the nuclei and the primary particles present determine the formation of dense smooth secondary particles with significantly lower macroporosity during heat treatment. The removal of moisture from the voids formed during the polycondensation of long polymer chains results in the formation of mesoporous, which determine the large specific surface area of the particles and prevent the formation of large crystals during firing. Notably, the formation of excessively dense aggregates might result in their destruction during calcination. Thus, the regulation of zirconium polynuclear hydroxo complex polymer chains length allows control of the roughness and porosity of zirconia powders obtained via the CDJP method. This can be useful in the production of powders for gas-thermal spraying.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe CDJP method allows hydrated zirconia particles and zirconia powders with different sizes, morphologies, and structures to be obtained by varying the degree of Zr(IV) polymerization in the initial solution. A mechanism for the aggregation of particles obtained via the CDJP method from solutions with different degrees of polymerization was proposed. An increase in the degree of Zr (IV) polymerization in solution leads to a decrease in the size of crystallites and an increase in the diameter of primary and secondary particles, which allows denser aggregates to be obtained. Conversely, the use of nonpolymerized Zr (IV) in solution allows more crystallized samples, with smaller diameter primary and secondary particles, which are formed into loose agglomerates, to be obtained.\u003c/p\u003e \u003cp\u003eOn behalf of all authors, the corresponding author states that there is no conflict of interest.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eSupplementary data\u003c/h2\u003e \u003cp\u003eElectronic Supplementary Material associated with this article can be found in the online version of this paper (DOI: xxxxxxxxxx).\u003c/p\u003e \u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBremholm M, Birkedal H, Iversen BB, Pedersen JS (2015) Structural Evolution of Aqueous Zirconium Acetate by Time-Resolved Small-Angle X-ray Scattering and Rheology. 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Sep and Pur Tech 329:125157. https://doi.org/10.1016/j.seppur.2023.125157\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"chemical-papers","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"chpa","sideBox":"Learn more about [Chemical Papers](http://link.springer.com/journal/11696)","snPcode":"11696","submissionUrl":"https://www.editorialmanager.com/CHPA/default.aspx","title":"Chemical Papers","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Hydrated zirconia xerogel, zirconia powder, olation, oxolation, zirconium polymerization, population balance method","lastPublishedDoi":"10.21203/rs.3.rs-6175824/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6175824/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn this study, the effect of the Zr(IV) polymerization degree in a nitric acid solution on the characteristics of hydrated zirconia particles and zirconia powders was investigated. Samples of hydrated zirconia were produced via the controlled double-jet precipitation (CDJP) method. The degree of Zr (IV) polymerization in the solution was varied by modifying the NO\u003csub\u003e3\u003c/sub\u003e /ZrO\u003csup\u003e2+\u003c/sup\u003e ratio. The properties of the hydrated zirconia particles and zirconia powders formed after calcination were investigated via laser diffraction, optical and scanning electron microscopy, X-ray phase analysis, thermogravimetry and BET. The polymerization of Zr (IV) involves the formation and elongation of polymer chains consisting of tetramers of Zr\u003csub\u003e4\u003c/sub\u003e(OH)\u003csub\u003e8\u003c/sub\u003e(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e8\u003c/sub\u003e. An increase in the degree of Zr (IV) polymerization leads to a decrease in the size of the crystallites and an increase in the diameter of the primary particles. This facilitated the formation of dense aggregates with significantly reduced macroporosity. The mechanism of particle aggregation obtained by the CDJP method from a zirconium oxynitrate solution with different degrees of Zr(IV) polymerization was established and discussed in detail.\u003c/p\u003e","manuscriptTitle":"Polymerization of Zr (IV) in an oxynitrate solution: effects on the nucleation and aggregation of hydrated ZrO2","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-31 13:07:49","doi":"10.21203/rs.3.rs-6175824/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2025-03-23T03:46:39+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-03-22T16:54:44+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Chemical Papers","date":"2025-03-09T06:05:13+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-08T14:22:48+00:00","index":"","fulltext":""},{"type":"submitted","content":"Chemical Papers","date":"2025-03-07T02:11:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"chemical-papers","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"chpa","sideBox":"Learn more about [Chemical Papers](http://link.springer.com/journal/11696)","snPcode":"11696","submissionUrl":"https://www.editorialmanager.com/CHPA/default.aspx","title":"Chemical Papers","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"644957ee-5ce9-4182-af77-e873a7743bb3","owner":[],"postedDate":"March 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-07-07T15:59:11+00:00","versionOfRecord":{"articleIdentity":"rs-6175824","link":"https://doi.org/10.1007/s11696-025-04160-y","journal":{"identity":"chemical-papers","isVorOnly":false,"title":"Chemical Papers"},"publishedOn":"2025-07-01 15:56:52","publishedOnDateReadable":"July 1st, 2025"},"versionCreatedAt":"2025-03-31 13:07:49","video":"","vorDoi":"10.1007/s11696-025-04160-y","vorDoiUrl":"https://doi.org/10.1007/s11696-025-04160-y","workflowStages":[]},"version":"v1","identity":"rs-6175824","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6175824","identity":"rs-6175824","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}