Preparation of open-cell catalytic foam with deposited TiO2-CeO2 by using subcritical water crystallization

Preparation of open-cell catalytic foam with deposited TiO2-CeO2 by using subcritical water crystallization | 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 Preparation of open-cell catalytic foam with deposited TiO 2 -CeO 2 by using subcritical water crystallization Ivana Troppová, Michal Zym, Lenka Matějová This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8618771/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study investigates the design of thin film/s of TiO 2 -CeO 2 catalyst deposited on commercial open-cell ceramic foam in subcritical water which is a unique preparation technique and previously unstudied. This work is focused on the investigation of the effect of subcritical water permeation through the parent ceramic foam using different engineering arrangement in the column and the number of catalyst layers deposited on ceramic foam surface. Environmental Chemistry titania ceria mixed oxide catalyst VUKOPOR®A ceramic foam subcritical water crystallization/processing Figures Figure 1 1. Introduction It is well established that thin films are studied in the field of materials science and engineering [ 1 ]. The ability to customize film properties by adjusting the microstructure through specific preparation parameters in a chosen technique has enabled their application across a wide range of fields [ 1 ]. These include simpler uses like protective coatings against wear [ 2 , 3 ] or [ 4 , 5 ] corrosion, as well as cutting-edge advancements in areas such as microelectronics [ 6 ], biomedicine [ 7 , 8 ] or chemistry [ 9 – 12 ] industry. This study investigates the design of thin film/s of TiO 2 -CeO 2 catalyst deposited on commercial open-cell ceramic foam in subcritical water which is a unique preparation technique and previously unstudied. This work is focused on the investigation of the effect of subcritical water permeation through the parent ceramic foam using different engineering arrangement in the column and the number of catalyst layers deposited on ceramic foam surface. Reported studies in this field suggest that TiO 2 -based nanocrystalline thin films and technologies working with subcritical and supercritical water or water and organic solvent-modified supercritical CO 2 may lead to nanocrystalline inorganic materials/metal oxides with high specific surface area [ 13 – 16 ], which may have a positive effect on their catalytic and photocatalytic performance [ 17 – 19 ]. With regard to TiO 2 -CeO 2 mixtures, adding cerium/CeO 2 to TiO 2 reduces the size of the TiO 2 anatase crystallites and increases their thermal stability. It also increases reducibility and Lewis and Brønsted acidity because it is desirable, e.g. for catalytic oxidation of selected VOCs [ 17 ]. Moreover, for industrial applications, a catalyst in monolithic form is preferable prior to granulated form, which includes additional advantages such as better transport properties, improved thermal stability, improved accessibility of catalyst active surface area etc [ 18 ]. The use of a monolith as a catalyst also carries with it some negative aspects that could be avoided by finding a new type of support [ 17 – 19 ]. 2. Experimental The experimental part deals with the deposition of one or two layers of TiO 2 -CeO 2 with a molar composition of Ti: Ce = 0.9:0.1 on open-cell VUKOPOR®A ceramic foam from the Czech company LANIK, s.r.o. by using the sol-gel method controlled in reverse micelles environment and high-pressure subcritical water treatment/processing up to 250°C and 30 MPa ( signed SubW) or conventional calcination at 500°C ( signed Calc), followed by physicochemical characterization using nitrogen physisorption at 77 K, phase carbon determination and scanning electron microscopy with energy-dispersive X-ray spectroscopy. 3. Characterization Prepared TiO 2 -CeO 2 @VUKOPOR®A foams were characterized by nitrogen physisorption at 77K by using a 3Flex (Micromeritics, USA) to determine their porous structure morphology, especially the specific surface area and the net pore volume. The phase carbon was determined on a Leco RC612 (Leco, The Netherlands) controlled oxidation or pyrolysis of the catalytic foam (depending on the selected atmosphere) in a furnace with programmed heating. Microphotographs were obtained by using a scanning electron microscope (SEM) Tescan Vega (Czech Republic) with tungsten cathode. The combination of secondary electron (SE) and backscattered electron (BSE) modes (SE + BSE) and energy dispersive X-ray spectroscopy (EDS:EDAX) with an accelerating voltage of 15 KeV was used.. The materials were imaged prior to sputtered with gold to ensure adequate electron conductivity. 4. Results At elevated temperatures of 200°C and pressures above 10 MPa the subcritical water processing results in leaching of Al 3+ from the VUKOPOR®A ceramic foam, which means that the ceramic foam is not chemically stable, and this causes that there are wrinkles formed on the surface of the ceramic foams and their specific surface area increases from ∼0.3 m 2 .g − 1 to ∼1 m 2 .g − 1 (Fig. 1). The macroporosity of parent open-cell VUKOPOR®A ceramic foams is significantly influenced by temperature. During the processing of TiO 2 -CeO 2 @VUKOPOR®A foams in subcritical water a part of the TiO 2 -CeO 2 catalyst layer is probably washed away, which leads to a decrease in the mass of the catalyst layer. However, the TiO 2 -CeO 2 catalyst layer is highly porous and has an increased specific surface area compared to parent open-cell VUKOPOR®A ceramic foam (Fig. 1). When TiO 2 -CeO 2 @VUKOPOR®A foams are processed by calcination, complete removal of organic carbon is reached and the foam with one layer of TiO 2 -CeO 2 catalyst has ∼3 times higher specific surface area comparing to that one from subcritical water processing, where some organic carbon remains in the TiO 2 -CeO 2 @VUKOPOR®A foams. The different engineering arrangement in the column (bead size used in the high-pressure cartridge) during the subcritical water processing of TiO 2 -CeO 2 @VUKOPOR®A foams does not affect the resulting properties of the catalyst layer. Declarations Funding The financial support of the European Union under the REFRESH - Research Excellence For REgion Sustainability and High-tech Industries project No. CZ.10.03.01/00/22_003/0000048 via the Operational Programme Just Transition is gratefully acknowledged. The research was also funded by the OP JAK project "INOVO!!!" No. CZ.02.01.01/00/23_021/0008588 supported by the Ministry of Education, Youth and Sports and co-financed by the European Union. Experimental results were accomplished using Large Research Infrastructure ENREGAT supported by the Ministry of Education, Youth and Sports of the Czech Republic (projects No. LM2018098 and No. LM2023056). Data availability Open research data will be available on Zenodo in the final version of the manuscript. References E. Acosta, Thin Films/Properties and Applications, in: A.E. Ares (Ed.) Thin Films, IntechOpen, Rijeka, 2021. M. Awang, A.A. Khalili, S.R. Pedapati, A Review: Thin Protective Coating for Wear Protection in High-Temperature Application, Metals, 2020. M. Sathish, N. Radhika, B. Saleh, Current Status, Challenges, and Future Prospects of Thin Film Coating Techniques and Coating Structures, Journal of Bio- and Tribo-Corrosion, 9 (2023) 35. R. Hübler, A. Cozza, T.L. Marcondes, R.B. Souza, F.F. Fiori, Wear and corrosion protection of 316-L femoral implants by deposition of thin films, Surf Coat Technol, 142-144 (2001) 1078–1083. V. Dykin, A. Jonsson, I. Pázsit, Qualitative and quantitative investigation of the propagation noise in various reactor systems, Progress in Nuclear Energy, 70 (2014) 98–111. J. Schmitz, Low temperature thin films for next-generation microelectronics (invited), Surf Coat Technol, 343 (2018) 83–88. P. Parthasarathy, S. Vivekanandan, Biocompatible TiO 2 -CeO 2 Nano-composite synthesis, characterization and analysis on electrochemical performance for uric acid determination, Ain Shams Eng J, 11 (2020) 777–785. F. Fang, M. Li, J. Zhang, C.-S. Lee, Different Strategies for Organic Nanoparticle Preparation in Biomedicine, ACS Mater Lett, 2 (2020) 531–549. F. Cansell, C. Aymonier, A. Loppinet-Serani, Review on materials science and supercritical fluids, Curr Opin Solid St M, 7 (2003) 331–340. Y. Hakuta, H. Hayashi, K. Arai, Fine particle formation using supercritical fluids, Curr Opin Solid St M, 7 (2003) 341–351. S.J. Teichner, G.A. Nicolaon, M.A. Vicarini, G.E.E. Gardes, Inorganic Oxide Aerogels, Adv Colloid Interfac, 5 (1976) 245–273. O. Zegaoui, C. HoangVan, M. Karroua, Selective catalytic reduction of nitric oxide by propane over vanadia-titania aerogels, Appl Catal B-Environ, 9 (1996) 211–227. M. Sajfrtová, M. Cerhová, V. Dřínek, S. Daniš, L. Matějová, Preparation of nanocrystalline titania thin films by using pure and water-modified supercritical carbon dioxide, J Supercrit Fluid, 117 (2016) 289–296. M. Sajfrtová, M. Cerhová, V. Jandová, V. Dřínek, S. Daniš, L. Matějová, The effect of type and concentration of modifier in supercritical carbon dioxide on crystallization of nanocrystalline titania thin films, J Supercrit Fluid, 133 (2018) 211–217. M. Cerhová, L. Matějová, V. Jandová, S. Daniš, V. Dřínek, M. Sajfrtová, Preparation of nanocrystalline TiO monoliths by using modified supercritical carbon dioxide, J Supercrit Fluid, 137 (2018) 93–100. M. Sajfrtová, M. Cerhová, V. Jandová, V. Dřínek, S. Daniš, L. Matějová, The effect of type and concentration of modifier in supercritical carbon dioxide on crystallization of nanocrystalline titania thin films, J Supercrit Fluid, 133 (2018) 211–217. L. Matějová, I. Troppová, S. Pitkäaho, K. Pacultová, D. Fridrichová, O. Kania, R. Keiski, Oxidation of Methanol and Dichloromethane on TiO‑CeO-CuO, TiO-CeO and TiO‑CuO@VUKOPOR A Ceramic Foams, Nanomaterials-Basel, 13 (2023). I. Troppová, L. Matejová, K. Karásková, S. Pitkäaho, V. Papaefthimiou, B. Louis, O. Kania, R.L. Keiski, Monolithic TiO-CeO and Pt/TiO-CeO@VUKOPOR®A foams in oxidation of dichloromethane and methanol, J Environ Chem Eng, 13 (2025). A. Klegova, K. Pacultová, T. Kiska, P. Peikertová, A. Rokicinska, P. Kustrowski, L. Obalová, Washcoated open-cell foam cobalt spinel catalysts for N2O decomposition, Mol Catal, 533 (2022). Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-8618771","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":575593431,"identity":"6d0eca7a-d38c-4f77-a242-1c2d3d4f41e3","order_by":0,"name":"Ivana 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08:44:18","extension":"html","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":39687,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8618771/v1/b6f871c6a0e73624a0246ebd.html"},{"id":100561637,"identity":"97e69765-80e4-48f1-8f08-788a18208513","added_by":"auto","created_at":"2026-01-19 08:44:10","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":2518442,"visible":true,"origin":"","legend":"\u003cp\u003eSpecific surface area and Al\u003csup\u003e3+\u003c/sup\u003e\u0026nbsp;content in parent open-cell ceramic foam and treated foams.\u003c/p\u003e","description":"","filename":"PrePrintFig600dpi.png","url":"https://assets-eu.researchsquare.com/files/rs-8618771/v1/d18e95a5a6613d162b1cc725.png"},{"id":100729730,"identity":"6b8eb4d2-d3e9-47e8-895f-7ca0fcbd2463","added_by":"auto","created_at":"2026-01-20 21:14:46","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2864898,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8618771/v1/26bd5688-b240-445b-a9ad-19fdb43ffcd1.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003ePreparation of open-cell catalytic foam with deposited TiO\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e-CeO\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e by using subcritical water crystallization\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eIt is well established that thin films are studied in the field of materials science and engineering [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The ability to customize film properties by adjusting the microstructure through specific preparation parameters in a chosen technique has enabled their application across a wide range of fields [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. These include simpler uses like protective coatings against wear [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] or [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] corrosion, as well as cutting-edge advancements in areas such as microelectronics [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], biomedicine [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] or chemistry [\u003cspan additionalcitationids=\"CR10 CR11\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] industry.\u003c/p\u003e \u003cp\u003eThis study investigates the design of thin film/s of TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e catalyst deposited on commercial open-cell ceramic foam in subcritical water which is a unique preparation technique and previously unstudied. This work is focused on the investigation of the effect of subcritical water permeation through the parent ceramic foam using different engineering arrangement in the column and the number of catalyst layers deposited on ceramic foam surface. Reported studies in this field suggest that TiO\u003csub\u003e2\u003c/sub\u003e-based nanocrystalline thin films and technologies working with subcritical and supercritical water or water and organic solvent-modified supercritical CO\u003csub\u003e2\u003c/sub\u003e may lead to nanocrystalline inorganic materials/metal oxides with high specific surface area [\u003cspan additionalcitationids=\"CR14 CR15\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], which may have a positive effect on their catalytic and photocatalytic performance [\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. With regard to TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e mixtures, adding cerium/CeO\u003csub\u003e2\u003c/sub\u003e to TiO\u003csub\u003e2\u003c/sub\u003e reduces the size of the TiO\u003csub\u003e2\u003c/sub\u003e anatase crystallites and increases their thermal stability. It also increases reducibility and Lewis and Br\u0026oslash;nsted acidity because it is desirable, \u003cem\u003ee.g.\u003c/em\u003e for catalytic oxidation of selected VOCs [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Moreover, for industrial applications, a catalyst in monolithic form is preferable prior to granulated form, which includes additional advantages such as better transport properties, improved thermal stability, improved accessibility of catalyst active surface area etc [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. The use of a monolith as a catalyst also carries with it some negative aspects that could be avoided by finding a new type of support [\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e"},{"header":"2. Experimental","content":"\u003cp\u003eThe experimental part deals with the deposition of one or two layers of TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e with a molar composition of Ti: Ce\u0026thinsp;=\u0026thinsp;0.9:0.1 on open-cell VUKOPOR\u0026reg;A ceramic foam from the Czech company LANIK, s.r.o. by using the sol-gel method controlled in reverse micelles environment and high-pressure subcritical water treatment/processing up to 250\u0026deg;C and 30 MPa (\u003cem\u003esigned\u003c/em\u003e SubW) or conventional calcination at 500\u0026deg;C (\u003cem\u003esigned\u003c/em\u003e Calc), followed by physicochemical characterization using nitrogen physisorption at 77 K, phase carbon determination and scanning electron microscopy with energy-dispersive X-ray spectroscopy.\u003c/p\u003e"},{"header":"3. Characterization","content":"\u003cp\u003ePrepared TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e@VUKOPOR\u0026reg;A foams were characterized by nitrogen physisorption at 77K by using a 3Flex (Micromeritics, USA) to determine their porous structure morphology, especially the specific surface area and the net pore volume. The phase carbon was determined on a Leco RC612 (Leco, The Netherlands) controlled oxidation or pyrolysis of the catalytic foam (depending on the selected atmosphere) in a furnace with programmed heating. Microphotographs were obtained by using a scanning electron microscope (SEM) Tescan Vega (Czech Republic) with tungsten cathode. The combination of secondary electron (SE) and backscattered electron (BSE) modes (SE\u0026thinsp;+\u0026thinsp;BSE) and energy dispersive X-ray spectroscopy (EDS:EDAX) with an accelerating voltage of 15 KeV was used.. The materials were imaged prior to sputtered with gold to ensure adequate electron conductivity.\u003c/p\u003e"},{"header":"4. Results","content":"\u003cp\u003eAt elevated temperatures of 200\u0026deg;C and pressures above 10 MPa the subcritical water processing results in leaching of Al\u003csup\u003e3+\u003c/sup\u003e from the VUKOPOR\u0026reg;A ceramic foam, which means that the ceramic foam is not chemically stable, and this causes that there are wrinkles formed on the surface of the ceramic foams and their specific surface area increases from \u0026sim;0.3 m\u003csup\u003e2\u003c/sup\u003e.g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e to \u0026sim;1 m\u003csup\u003e2\u003c/sup\u003e.g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Fig.\u0026nbsp;1). The macroporosity of parent open-cell VUKOPOR\u0026reg;A ceramic foams is significantly influenced by temperature.\u003c/p\u003e \u003cp\u003eDuring the processing of TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e@VUKOPOR\u0026reg;A foams in subcritical water a part of the TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e catalyst layer is probably washed away, which leads to a decrease in the mass of the catalyst layer. However, the TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e catalyst layer is highly porous and has an increased specific surface area compared to parent open-cell VUKOPOR\u0026reg;A ceramic foam (Fig.\u0026nbsp;1). When TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e@VUKOPOR\u0026reg;A foams are processed by calcination, complete removal of organic carbon is reached and the foam with one layer of TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e catalyst has \u0026sim;3 times higher specific surface area comparing to that one from subcritical water processing, where some organic carbon remains in the TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e@VUKOPOR\u0026reg;A foams.\u003c/p\u003e \u003cp\u003eThe different engineering arrangement in the column (bead size used in the high-pressure cartridge) during the subcritical water processing of TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e@VUKOPOR\u0026reg;A foams does not affect the resulting properties of the catalyst layer.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe financial support of the European Union under the REFRESH - Research Excellence For REgion Sustainability and High-tech Industries project No. CZ.10.03.01/00/22_003/0000048 via the Operational Programme Just Transition is gratefully acknowledged. The research was also\u0026nbsp;funded by the OP JAK project \"INOVO!!!\" No. CZ.02.01.01/00/23_021/0008588 \u0026nbsp;supported by the Ministry of Education, Youth and Sports and co-financed by the European Union.\u0026nbsp;Experimental results were accomplished using Large Research Infrastructure ENREGAT supported by the Ministry of Education, Youth and Sports of the Czech Republic (projects No.\u0026nbsp;LM2018098 and No. LM2023056).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOpen research data will be available on Zenodo in the final version of the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eE. Acosta, Thin Films/Properties and Applications, in: A.E. Ares (Ed.) Thin Films, IntechOpen, Rijeka, 2021.\u003c/li\u003e\n\u003cli\u003eM. Awang, A.A. Khalili, S.R. 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Troppov\u0026aacute;, L. Matejov\u0026aacute;, K. Kar\u0026aacute;skov\u0026aacute;, S. Pitk\u0026auml;aho, V. Papaefthimiou, B. Louis, O. Kania, R.L. Keiski, Monolithic TiO-CeO and Pt/TiO-CeO@VUKOPOR\u0026reg;A foams in oxidation of dichloromethane and methanol, J Environ Chem Eng, 13 (2025).\u003c/li\u003e\n\u003cli\u003eA. Klegova, K. Pacultov\u0026aacute;, T. Kiska, P. Peikertov\u0026aacute;, A. Rokicinska, P. Kustrowski, L. Obalov\u0026aacute;, Washcoated open-cell foam cobalt spinel catalysts for N2O decomposition, Mol Catal, 533 (2022).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[{"identity":"14e5271b-d67d-4030-8842-0eca190fb573","identifier":"10.13039/501100000780","name":"European Commission","awardNumber":"CZ.10.03.01/00/22_003/0000048 ","order_by":0},{"identity":"ca23d1f1-24c2-42c7-9efa-38a9a7aa3054","identifier":"10.13039/501100001823","name":"Ministerstvo Školství, Mládeže a Tělovýchovy","awardNumber":"CZ.02.01.01/00/23_021/0008588","order_by":1},{"identity":"e087797f-2eb2-4d59-87e9-323fd4c60aac","identifier":"10.13039/501100001823","name":"Ministerstvo Školství, Mládeže a Tělovýchovy","awardNumber":"LM2018098","order_by":2},{"identity":"55501615-8f79-4254-a949-b6ac6a112e44","identifier":"10.13039/501100001823","name":"Ministerstvo Školství, Mládeže a Tělovýchovy","awardNumber":"LM2023056","order_by":3}],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"VSB-TUO","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"titania, ceria, mixed oxide catalyst, VUKOPOR®A ceramic foam, subcritical water crystallization/processing","lastPublishedDoi":"10.21203/rs.3.rs-8618771/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8618771/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study investigates the design of thin film/s of TiO\u003csub\u003e2\u003c/sub\u003e-CeO\u003csub\u003e2\u003c/sub\u003e catalyst deposited on commercial open-cell ceramic foam in subcritical water which is a unique preparation technique and previously unstudied. This work is focused on the investigation of the effect of subcritical water permeation through the parent ceramic foam using different engineering arrangement in the column and the number of catalyst layers deposited on ceramic foam surface.\u003c/p\u003e","manuscriptTitle":"Preparation of open-cell catalytic foam with deposited TiO2-CeO2 by using subcritical water crystallization","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-19 08:32:18","doi":"10.21203/rs.3.rs-8618771/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"41afe2c4-c2b2-40f1-b31c-52f02796c22b","owner":[],"postedDate":"January 19th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":61341509,"name":"Environmental Chemistry"}],"tags":[],"updatedAt":"2026-01-19T08:32:18+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-19 08:32:18","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8618771","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8618771","identity":"rs-8618771","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}