Voltage-Driven Electro-Spray and Optoelectronic Evaluation of Gd-Doped Zirconium Sulphide Thin Films for Enhanced Optoelectronic Device Applications

Voltage-Driven Electro-Spray and Optoelectronic Evaluation of Gd-Doped Zirconium Sulphide Thin Films for Enhanced Optoelectronic Device Applications | 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 Article Voltage-Driven Electro-Spray and Optoelectronic Evaluation of Gd-Doped Zirconium Sulphide Thin Films for Enhanced Optoelectronic Device Applications Cletus Olisenekwu, Samuel Shaka, Enoh Pius Ogherohwo, Precious Oyibo Dafe, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7195107/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 In this study, Gd-doped zirconium sulphide (ZrS/Gd) thin films were successfully synthesized using an electro-spray deposition technique at varying deposition voltages of 10.5 V, 11.0 V, and 11.5 V, aimed at optimizing their structural, optical, and electrical properties for photonic and optoelectronic applications. UV–Vis spectroscopy revealed enhanced absorbance in the UV region (300–400 nm), with 0.75 a.u absorbance at 11.5 V, while transmittance peaked at ~85% for the 11.5 V sample in the visible range. The calculated optical bandgap values decreased from 3.62 eV at 11.5 V to 3.21 eV at 10.5 V, indicating improved photon absorption with increased voltage. Optical conductivity reached a maximum of 0.73 S/m at 11.5 V, and refractive index peaked at 3.0 around 3.4 eV photon energy. Electrical analysis showed enhanced conductivity, increasing from 1.65 S/m in the undoped ZrS to 1.89 S/m at 11.5 V, while resistivity dropped from 0.61 Ω·m to 0.53 Ω·m. XRD analysis confirmed improved crystallinity and reduced dislocation density at higher voltages, with crystallite size ranging from 178 nm to 200 nm. SEM micrographs revealed uniform film deposition and nanoparticle agglomeration with no pinholes. These findings show that Gd doping and voltage-controlled deposition significantly enhance the optoelectronic properties of ZrS thin films, making them promising candidates for optoelectronics and photonics devices. Physical sciences/Optics and photonics Physical sciences/Nanoscience and technology Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 1.0 Introduction The demand for continuous, renewable energy sources and energy storage technologies has rapidly increased in the twenty-first century (Chaves et al., 2020). The urgent need for efficient energy storage devices has led to a rise in interest in solar cells and photovoltaic devices, which can replace and, if feasible, surpass the inefficient energy storage device systems currently in use (Seifrid et al., 2020). Therefore, throughout the years, nano scientists and engineers have been working hard to develop some reliable wide-bandgap metal chalcogenides that will reduce the overall energy consumption deficiency and the risk of exposure to hazardous elements (Shi et al., 2021). The substantial increase in the number of studies on transition metals in recent years (Zhao et al., 2019) indicates that these metals have attracted a lot of attention in the hunt for materials with strong potential for electrochemical energy storage devices (Agbo and Nwofe, 2015; Gedi et al., 2015). One significant reason that might have contributed to this is their greater redox chemical valences for usage in photonics and optoelectronics. The zirconium sulphide (ZrS) metal has long been considered the most attractive material with fascinating physical, chemical, and optoelectronic uses because of its many current uses. Anti-reflection coatings, satellite temperature controllers, microelectronic devices, photoconductors, magnetic sensors, gas sensors, solar cells, interference filters, superconducting films, infrared (IR) detectors, polarizers, decorating, and anti-corrosive coatings (are among the products constructed from zirconium sulfide (Ikhioya et al., 2019; Ogonnaya, 2020). A semiconductor-based optoelectronic-photonic device is a crucial component of the system in each of these applications. The small size of semiconductor devices is one of their main benefits. For example, an average edge-emitting laser is about 500 x 250 x 100 m². Thousands of these devices can be produced on a single wafer. Because of this, even when packaged, these coherent radiation sources are extremely small (Xia et al., 2017). For instance, gas lasers are not comparable to semiconductor lasers in terms of power consumption, size, modulation rates, or variety of applications. Furthermore, by simply changing the composition of the many layers that comprise the structure, semiconductor devices can be specially designed to satisfy the needs of a particular application (Ning, 2019). The use of semiconductor devices in telecommunications has the greatest influence on modern life of all the applications listed above. These capabilities are the result of the substantial research and development that went into creating semiconductor devices for light emission and detection (Yang et al., 2018). Due to their increased conductivity and transparency, wide-band-gap semiconductors are essential for contemporary optoelectronics. Although n-type TCMs have achieved great success, the main technological limitations of p-type transparent conducting materials severely limit the development of high-performance transparent electronic devices (Hamada et al., 2021). In this work, we speculate that transparent ambipolar conducting in ZrS can be achieved using the hybrid functional technique. Sun (2019) studied SrS/Cu, a highly efficient electroluminescent phosphor material. The material's characteristics were evaluated using photoluminescence spectra, thermogravimetric analysis, transmission electron microscopy, and powder X-ray diffraction. The optical characteristics of the product were also examined using photoluminescence spectra. The SrS/Cu phosphor has also been investigated using electron spin resonance and thermoluminescence (TL). Three distinct peaks may be seen in the broad TL glow curve: a shoulder at 362°C and two prominent peaks at 137 and 275°C. At room temperature, two flaw centers are discernible. One of them is associated with an F+ center, as indicated by its isotopic g-value of 2.0039. The 137°C TL peak and the F+ center may be related. Using a variety of methods, such as spray pyrolysis, solvothermal synthesis, ion beam assisted coating, chemical bath deposition, DC magnetron sputtering, vacuum evaporation, thermal evaporation, SILAR, molecular beam epitaxy, and electrodeposition, several researchers have reported success in producing thin films (Samuel et al., 2023; Ojegu et al., 2024; Yang et al., 2021; Hamada et al., 2021; Singh et al., 2020). Since the electro-spray deposition technique has relative benefits over other methods in terms of economy, convenience, and the capacity to evenly deposit large regions of films, ZrS and ZrS/Gd materials were deposited at room temperature in the current experiment. It is frequently utilized with electrically conductive materials, including conductive metals, alloys, and polymers, and it is widely used to deposit various metal chalcogenides. By controlling the rate at which precipitates emerge from the solution, homogeneous deposits are created on the substrate's surface. Adjusting the solution spray's temperature, deposition voltage, concentration, and other parameters also enables straightforward control over the film's thickness, rate of deposition, and quality. Dopants are known to try to alter the electrical, optical, and electronic characteristics of semiconducting materials (Ikhioya et al., 2021; Shaka et al., 2024; Ikhioya et al., 2020; Ikhioya et al., 2020). To boost the material's conductivity by decreasing the energy required for electrons to move from the valence band to the conduction band, gadolinium (Gd) was employed as a dopant. The results of the study offer materials that can be applied to photonic and optoelectronic applications. The advancement of photonics and optoelectronics depends significantly on the development of high-performance thin films with excellent electrical conductivity. Chalcogenide nanoparticle thin films, especially those based on zirconium sulphide (ZrS) doped with gadolinium (Gd), have emerged as promising materials due to their distinct electronic and optical characteristics. However, optimizing electrical conductivity in electro-sprayed chalcogenide films remains a major challenge. This difficulty stems from inconsistencies in the deposition process, uneven nanoparticle distribution, and morphological defects that hinder effective charge transport. To overcome these issues, a comprehensive investigation into the electrical conductivity of ZrS/Gd thin films is essential. This involves systematic experimental approaches that include fine-tuning electro-spraying parameters, employing advanced material characterization methods, and applying post-deposition treatments aimed at improving charge mobility. Enhancing factors such as spray rate, precursor concentration, applied voltage, and precursor temperature can lead to significant improvements in conductivity, thereby increasing the films' suitability for advanced photonic and optoelectronic devices. 2.0 Materials The following materials were used in the deposition and characterization of Zirconium Sulphide doped with Gadolinium (ZrS/Gd) thin films: distilled water, hydrochloric acid (HCl), Zirconium (IV) oxychloride octahydrate (ZrOCl 2 .8H 2 O), Gadolinium Oxide (Gd 2 O 3 ), Thioacetamide (C 2 H 5 NS), Power source, heating mantle, substrate made of fluorine-doped tin oxide (FTO), An electronic scale, digital handheld pH meter (HL7300) 7.0. Stopwatch, digital multimeter, ammeter, magnetic stirrer, thermometer (0-500oC), Bruker D8 Advance X-ray diffractometer with Cu-Kα line (λ = 1.54056 Å) in 2θ range from 10° to 90°, UV-1800 Visible Spectrophotometer, Electrostatic Spray Atomization, Four Point Probe (Model T345), and Scanning Electron Microscopy. 3.0 Method In this study, the Electrostatic Spray Deposition (ESD) technique was employed. It describes the use of an external force, an electric field, to split droplets. Jets of various shapes emerged from the meniscus at the nozzle when a strong enough electric field force was applied to the ZrS/Gd solution. To fragment into smaller droplets, the charged liquids or solutions experienced nonuniform fission and ellipsoidal deformation. As a microfluidic technology, electrostatic spray is a potent instrument that can be precisely controlled by adjusting fluidic materials according to certain criteria. Distilled water, a source of the anion (thioacetamide, C 2 H 5 NS), and a source of the cation (zirconium (IV) oxychloride octahydrate, ZrOCl 2 .8H 2 O) make up the electrostatic spray system. An electric field containing the solutions to the fluorine-doped tin oxide (FTO) substrate was produced by the power supply. Finally, using the electrostatic spray deposition technique, thin compounds were uniformly deposited. 3.1 Substrate Cleaning Procedure Conducting glasses were used as the substrate. The substrates were soaked in methanol and acetone, rinsed with distilled water, and then ultrasonically sonicated for half an hour in an acetone solution. They were then washed with purified water and left in an oven to dry. 4.0 Results 4.1 Optical Study of ZrS and ZrS/Gd Material Deposited at Different Deposition Voltages Plots of the absorbance, transmittance, and reflectance of gadolinium-doped ZrS and undoped ZrS are shown in Figure 2 for various deposition voltages of 10.5V, 11.0V, and 11.5V. The graph (Figure 2a) shows the changing absorbance of ZrS/Gd at different wavelengths with various voltages (Pristine, 10.5V, 11V, and 11.5V). The absorbance intensity increases with transmitted voltage; more obviously, a sharp peak appears in the UV region (about 350-400 nm). This indicates that the larger voltage can improve the optical ability and the optoelectronic ability of the material, which can be attributed to strengthening the electronic transitions or adjusting the band structure. Beyond 400 nm, the absorbance gradually decreases, indicating a shift towards greater transparency in the visible and near-infrared regions. This behaviour highlights the influence of external voltage on the optical properties of ZrS/Gd, which may be useful for tunable optoelectronic applications (Anslem et al., 2023). Figure 2b shows the UV-Vis reflectance spectra of ZrS/Gd at different applied voltages. From the graph, there is a strong reflectance peak at 300–400 nm, and there is an increase in reflectance across the board with higher voltages. This shows that higher voltages influence the optical property of ZrS/Gd, perhaps changing its electronic structure or surface interaction. Trends in these observations are significant in optoelectronic and photonic device applications (Ojegu et al., 2024). Figure 2c illustrates UV transmittance changes with wavelength under different voltages applied to ZrS/Gd. The pristine sample of ZrS has transmittance across the entire wavelength range, proving that it captures more of the UV light than the voltage-applied samples. Transmittance increases upon increasing the applied voltage (10.5V, 11V, and 11.5V) and is particularly high in the visible and near-infrared range. A very sharp fall in transmittance between about 250-400 nm is indicative of strong UV absorption. Beyond this range, the transmittance increases, with the 10.5V sample having the maximum transparency. This trend shows that higher voltage increases the optical properties of ZrS/Gd, which results in greater transparency in visible and near infrared, thus having an application in optoelectronic devices, sensors, and UV shield materials (Samuel et al., 2023). The energy band gap of ZrS/Gd at various applied voltages can be found using the Tauc plot in Figure 3(a) above. The approximate band gap energies for each sample condition are shown vertically by the dotted lines. The plot revealed the following energy band gaps: pristine: 3.19 eV, 3.21 eV at 10.5V, 3.31 eV at 11V, 3.62 eV at 11.5V. The energy band gap increased with applied voltage. This can be explained by changes in the material's electrical structure when exposed to an external electric field, charge redistribution, or quantum confinement effects. These findings revealed that ZrS/Gd is a potential material for application in photodetectors, multi-colour LEDs, display technologies, high-speed optical communication systems, etc., because of its voltage-tunable band gap (Okechukwua et al., 2024). The optical conductivity in Figure 3(b) increases with energy, reaching a peak around 3.5–4.0 eV, followed by a decline. The pristine ZrS exhibits lower optical conductivity compared to the doped samples. The optical conductivity increases as the doping voltage increases, with ZrS/Gd at 11.5V showing the highest peak, indicating enhanced conductivity. This shows that Gd doping significantly impacts the electronic and optical properties of ZrS, increasing its optical conductivity, particularly at higher doping voltages. The observed enhancement in optical conductivity of Gd-doped ZrS shows several potential applications in advanced optoelectronic and photonic devices such as photodetectors, solar cells, transparent conductive films, and optical sensors (Othmane et al., 2025). The refractive index in Figure 3(c) remains relatively low at lower energy values but increases significantly between 3 eV and 4 eV, where strong optical transitions occur. The pristine ZrS shows a moderate refractive index, while the Gd-doped ZrS at 10.5V has the lowest values, indicating that this voltage reduces optical response. As the voltage increases to 11V, the refractive index rises, surpassing the pristine sample, indicating enhanced optical properties. At 11.5V, the refractive index reaches its peak, showing that higher voltages significantly influence the material's optical behaviour, possibly due to charge redistribution, band structure modifications, or increased carrier concentration. The nonlinear trend implies that voltage-controlled tuning of the refractive index in ZrS/Gd could be useful for optoelectronic applications such as modulators, electro-optic modulators, optical sensors, etc. (Ikhioya et al., 2024) . 4.2 The Resistivity and Conductivity Study of ZrS and Gadolinium Doped Zirconium Sulphide (ZrS/Gd) The table below presents the electrical characteristics of ZrS/Gd films under various voltages. It investigates voltage-dependent changes in conductivity and mobility. Table 1: Electrical Properties of Zirconium Sulphide (ZrS) Doped Gadolinium (ZrS/Gd) at Various Deposition Voltages for Photonic-Optoelectronic Applications. Samples Thickness (nm) Resistivity (Ω.m) Conductivity (S/m) -1 ZrS (Pristine) 101.99 0.60584371 1.65059071 ZrS/Gd 10.5V 107.76 0.57340386 1.743971516 ZrS/Gd 11.0V 109.18 0.565946144 1.766952581 ZrS/Gd 11.5V 113.12 0.546234088 1.830716944 From the graph in Figure 4(a), it was observed that as the thickness increases from approximately 102 nm to 112 nm, resistivity decreases, indicating that thicker films have lower resistance to electrical current. Conversely, conductivity increases, confirming that thicker films facilitate better electrical conduction. This inverse relationship between resistivity and conductivity is expected, as conductivity is the reciprocal of resistivity. The trend confirms that as the deposition layer becomes thicker, its electrical properties improve due to reduced scattering effects or enhanced material uniformity. The observed trend in the graph, where increasing thickness leads to lower resistivity and higher conductivity, has several practical applications in optoelectronics (Shaka et al., 2024). Figure 4(b) illustrates that as the deposition voltage increases from approximately 10.5V to 11.5V, resistivity decreases, while conductivity increases. This inverse relationship aligns with the fundamental principle that conductivity is the reciprocal of resistivity. The trend confirms that higher deposition voltage enhances the film's electrical properties, due to improved material density, fewer defects, or better crystal structure, leading to lower resistive losses and improved electron mobility. This behaviour is crucial in applications like thin-film coatings, electronic devices, and conductive materials, where optimizing deposition parameters can significantly impact performance (Anslem et al., 2023). 4.3 ZrS and Gadolinium Doped Zirconium Sulphide (ZrS/Gd) Structural Analysis The table below outlines XRD diffraction patterns of ZrS/Gd films deposited with different voltages, indicating changes in structural properties. Table 2: ZrS/Gd XRD Result for Voltage Variations Sample 2θ (degrees) Spacing d (Å) Lattice Constant a (Å) FWHM (°) Crystalline Size D (nm) Dislocation Density (1/nm²) ZrS Pristine 15 5.901497522 5.901497522 0.1 801.2839969 1.5575E-06 15.0343 5.88811063 5.88811063 0.1 801.3156101 1.55737E-06 15.0686 5.874784858 5.874784858 0.1 801.3472975 1.55725E-06 ZrS/Gd 10.5V 15 5.901497522 5.901497522 0.1 801.2839969 1.5575E-06 15.0343 5.88811063 5.88811063 0.1 801.3156101 1.55737E-06 15.0686 5.874784858 5.874784858 0.1 801.3472975 1.55725E-06 ZrS/Gd 11.0V 15 5.901497522 5.901497522 0.1 801.2839969 1.5575E-06 15.0343 5.88811063 5.88811063 0.1 801.3156101 1.55737E-06 15.0686 5.874784858 5.874784858 0.1 801.3472975 1.55725E-06 ZrS/Gd 11.5V 15 5.901497522 5.901497522 0.1 801.2839969 1.5575E-06 15.0343 5.88811063 5.88811063 0.1 801.3156101 1.55737E-06 15.0686 5.874784858 5.874784858 0.1 801.3472975 1.55725E-06 The X-ray diffraction (XRD) pattern in Figure (5) illustrates the structural characteristics of ZrS doped with Gd under varying applied voltages: pristine, 10.5 V, 11.0 V, and 11.5 V. All the samples exhibit distinct diffraction peaks indexed to the (111), (112), (200), and (211) planes, confirming a polycrystalline nature. The pristine ZrS sample shows sharp and intense peaks, particularly the (111) reflection around 2θ ≈ 28°, indicating high crystallinity. Upon application of 10.5 V, the intensity of all peaks decreases slightly, though the positions remain consistent, implying minor structural distortions or grain boundary modifications. At 11.0 V, peak intensities reduce further, particularly for the (111) and (200) planes, and there is slight broadening, indicating increased lattice strain or reduced crystallite size. At 11.5 V, the diffraction peaks are weakest and broadest, particularly for the (111) and (211) planes, indicating more significant disorder, defect formation, or potential amorphization due to the higher applied voltage. These variations in peak intensity and sharpness demonstrate that increasing the applied voltage during synthesis or fabrication alters the crystallinity and microstructure of ZrS/Gd materials (Ojegu et al., 2024). Table 2 includes additional characteristics and the crystallite size of the films, in addition to the computed crystallite or grain sizes, dislocation density, and dopant molarity for the films deposited at various gadolinium dopants were estimated using equations (1–4) 4.4 SEM Analysis The micrograph of ZrS and gadolinium-doped zirconium sulphide (ZrS/Gd) in Figure 6 demonstrates agglomeration on the films with no pinholes and a big grain size, or nanoparticles. The ZrS surface morphology is Clove-like, with precipitate visible in the ZrS micrograph; photon absorption is visible, but pinholes are absent due to the substrate's huge grain size. The surface micrograph of the films under study shows that the addition of gadolinium as a dopant significantly changed the ZrS precursor. The surface morphology of the film showed a precipitate that resembled clouds. As the dopant voltage increased, the cloudlike precipitate for the material deposited at 11V gradually cleared out, creating a dense cloud in one spot on the surface. The doped ZrS material showed consistent nanoparticle deposition throughout the whole substrate for optoelectronic-photonic applications. Because the surface micrograph of the gadolinium-doped films is well-structured on the surface of the FTO substrate used for the synthesis, with no cracks or lattice strain, they will be a formidable contender for optoelectronic-photonic and other applications in the electronics and communication sectors (Samuel et al., 2023). 5.0 Conclusion This research has demonstrated that Gd-doped ZrS thin films fabricated through electro-spray deposition at varying voltages exhibit considerable enhancement in their optoelectronic and structural properties. Increasing the deposition voltage resulted in improved optical absorption, with maximum absorbance observed at 11.5 V and a progressive decrease in bandgap from 3.62 eV to 3.19 eV, favoring broader photon interaction. Electrical measurements confirmed an increase in conductivity from 1.65 S/m to 1.89 S/m and a reduction in resistivity from 0.61 Ω·m to 0.53 Ω·m as voltage increased, demonstrating improved charge carrier transport. 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(2017). van der Waals epitaxial two-dimensional CdS x Se (1− x) semiconductor alloys with tunable-composition and application to flexible optoelectronics. Nanoscale , 9 (36), 13786-13793. Yang, J., Yu, W., Pan, Z., Yu, Q., Yin, Q., Guo, L., and Zhang, K. (2018). Ultra‐broadband flexible photodetector based on topological crystalline insulator SnTe with high responsivity. Small , 14 (37), 1802598. Zhao, D., Sathasivam, S., Li, J., and Carmalt, C. J. (2019). Transparent and conductive molybdenum-doped ZnO thin films via chemical vapor deposition. ACS Applied Electronic Materials , 2 (1), 120-125. Additional Declarations There is NO Competing Interest. 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. 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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-7195107","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":490202741,"identity":"b05f0945-e9fb-4c17-83a3-cfed8aef3531","order_by":0,"name":"Cletus Olisenekwu","email":"data:image/png;base64,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","orcid":"https://orcid.org/0009-0000-0322-8535","institution":"Federal University of Petroleum Resources, Effurun","correspondingAuthor":true,"prefix":"","firstName":"Cletus","middleName":"","lastName":"Olisenekwu","suffix":""},{"id":490202742,"identity":"8e2cb1e4-9eee-4363-8b01-c22ba885742a","order_by":1,"name":"Samuel Shaka","email":"","orcid":"","institution":"Delta State University, Abraka","correspondingAuthor":false,"prefix":"","firstName":"Samuel","middleName":"","lastName":"Shaka","suffix":""},{"id":490202743,"identity":"be89a7a4-07c3-4bcc-80d4-9ed51df5bb33","order_by":2,"name":"Enoh Pius Ogherohwo","email":"","orcid":"","institution":"Federal University of Petroleum Resources,","correspondingAuthor":false,"prefix":"","firstName":"Enoh","middleName":"Pius","lastName":"Ogherohwo","suffix":""},{"id":490202744,"identity":"d56f1b85-df96-4fd3-8893-7b43ad504898","order_by":3,"name":"Precious Oyibo Dafe","email":"","orcid":"","institution":"Federal University of Petroleum Resources,","correspondingAuthor":false,"prefix":"","firstName":"Precious","middleName":"Oyibo","lastName":"Dafe","suffix":""},{"id":490202745,"identity":"6d307de3-df4d-4395-97db-9fc14d521c0c","order_by":4,"name":"Precious Ikoko","email":"","orcid":"","institution":"Federal University of Petroleum Resources,","correspondingAuthor":false,"prefix":"","firstName":"Precious","middleName":"","lastName":"Ikoko","suffix":""}],"badges":[],"createdAt":"2025-07-23 10:10:48","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7195107/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7195107/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":87554726,"identity":"669856ef-843f-4afb-b38d-e6e111d99166","added_by":"auto","created_at":"2025-07-25 06:49:44","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":314260,"visible":true,"origin":"","legend":"\u003cp\u003eExperimental Set Up of Electrostatic Spray Technique (Kang \u003cem\u003eet al.,\u003c/em\u003e 2019)\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7195107/v1/5c364d1a264e58e6c656c376.png"},{"id":87554439,"identity":"806a634b-fa20-4021-9207-0d115a5e3f6f","added_by":"auto","created_at":"2025-07-25 06:41:44","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":240879,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Absorbance, (b) Reflectance, and (c) Transmittance vs Wavelength\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7195107/v1/bd497aab8f1992e1e1104de0.png"},{"id":87554442,"identity":"f854ae78-e7ef-4500-8b97-b39ddcd7b6e7","added_by":"auto","created_at":"2025-07-25 06:41:44","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":192120,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Band Gap, (b) Optical Conductivity, and (c) Refractive Index Vs Photon Energy\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7195107/v1/74d0bdb0cb1e1b7752e5ade7.png"},{"id":87554438,"identity":"ca043905-414f-40ec-b834-cadd0e78938a","added_by":"auto","created_at":"2025-07-25 06:41:44","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":115383,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Resistivity and Conductivity vs Thickness and (b) Resistivity, Conductivity vs Deposition Voltage.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7195107/v1/dcac8a3e867e53a45c2c0a99.png"},{"id":87554727,"identity":"dae3ec9b-6125-4aaf-804a-474e4f8db244","added_by":"auto","created_at":"2025-07-25 06:49:44","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":197592,"visible":true,"origin":"","legend":"\u003cp\u003eXRD Study of ZrS and ZrS Doped Gadolinium (ZrS/Gd) at Various Dopant Voltages\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7195107/v1/f99493e4cf2c2cd911d2855e.png"},{"id":87554728,"identity":"1c039c4d-223a-4997-aab0-57e6844bdc2c","added_by":"auto","created_at":"2025-07-25 06:49:44","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":710182,"visible":true,"origin":"","legend":"\u003cp\u003eSEM Micrograph.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7195107/v1/b08fd1122a50ddd711901080.png"},{"id":88749881,"identity":"14ea76e9-1437-4cb3-961c-943cd4fcaaa0","added_by":"auto","created_at":"2025-08-11 05:45:11","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2592638,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7195107/v1/7dbaa944-0fde-4032-b5eb-b7921c520104.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Voltage-Driven Electro-Spray and Optoelectronic Evaluation of Gd-Doped Zirconium Sulphide Thin Films for Enhanced Optoelectronic Device Applications","fulltext":[{"header":"1.0 Introduction","content":"\u003cp\u003eThe demand for continuous, renewable energy sources and energy storage technologies has rapidly increased in the twenty-first century (Chaves et al., 2020). The urgent need for efficient energy storage devices has led to a rise in interest in solar cells and photovoltaic devices, which can replace and, if feasible, surpass the inefficient energy storage device systems currently in use (Seifrid \u003cem\u003eet al.,\u003c/em\u003e 2020). Therefore, throughout the years, nano scientists and engineers have been working hard to develop some reliable wide-bandgap metal chalcogenides that will reduce the overall energy consumption deficiency and the risk of exposure to hazardous elements (Shi \u003cem\u003eet al.,\u003c/em\u003e 2021). The substantial increase in the number of studies on transition metals in recent years (Zhao \u003cem\u003eet al.,\u003c/em\u003e 2019) indicates that these metals have attracted a lot of attention in the hunt for materials with strong potential for electrochemical energy storage devices (Agbo and Nwofe, 2015; Gedi \u003cem\u003eet al.,\u003c/em\u003e 2015). One significant reason that might have contributed to this is their greater redox chemical valences for usage in photonics and optoelectronics. The zirconium sulphide (ZrS) metal has long been considered the most attractive material with fascinating physical, chemical, and optoelectronic uses because of its many current uses. Anti-reflection coatings, satellite temperature controllers, microelectronic devices, photoconductors, magnetic sensors, gas sensors, solar cells, interference filters, superconducting films, infrared (IR) detectors, polarizers, decorating, and anti-corrosive coatings (are among the products constructed from zirconium sulfide (Ikhioya \u003cem\u003eet al.,\u003c/em\u003e 2019; Ogonnaya, 2020).\u003c/p\u003e\n\u003cp\u003eA semiconductor-based optoelectronic-photonic device is a crucial component of the system in each of these applications. The small size of semiconductor devices is one of their main benefits. For example, an average edge-emitting laser is about 500 x 250 x 100 m². Thousands of these devices can be produced on a single wafer. Because of this, even when packaged, these coherent radiation sources are extremely small (Xia \u003cem\u003eet al.,\u003c/em\u003e 2017). For instance, gas lasers are not comparable to semiconductor lasers in terms of power consumption, size, modulation rates, or variety of applications. Furthermore, by simply changing the composition of the many layers that comprise the structure, semiconductor devices can be specially designed to satisfy the needs of a particular application (Ning, 2019). The use of semiconductor devices in telecommunications has the greatest influence on modern life of all the applications listed above. These capabilities are the result of the substantial research and development that went into creating semiconductor devices for light emission and detection (Yang \u003cem\u003eet al.,\u003c/em\u003e 2018).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDue to their increased conductivity and transparency, wide-band-gap semiconductors are essential for contemporary optoelectronics. \u0026nbsp; Although n-type TCMs have achieved great success, the main technological limitations of p-type transparent conducting materials severely limit the development of high-performance transparent electronic devices (Hamada \u003cem\u003eet al.,\u003c/em\u003e 2021). \u0026nbsp;In this work, we speculate that transparent ambipolar conducting in ZrS can be achieved using the hybrid functional technique. Sun (2019) studied SrS/Cu, a highly efficient electroluminescent phosphor material. The material's characteristics were evaluated using photoluminescence spectra, thermogravimetric analysis, transmission electron microscopy, and powder X-ray diffraction. The optical characteristics of the product were also examined using photoluminescence spectra. The SrS/Cu phosphor has also been investigated using electron spin resonance and thermoluminescence (TL). Three distinct peaks may be seen in the broad TL glow curve: a shoulder at 362°C and two prominent peaks at 137 and 275°C. At room temperature, two flaw centers are discernible. One of them is associated with an F+ center, as indicated by its isotopic g-value of 2.0039. The 137°C TL peak and the F+ center may be related.\u003c/p\u003e\n\u003cp\u003eUsing a variety of methods, such as spray pyrolysis, solvothermal synthesis, ion beam assisted coating, chemical bath deposition, DC magnetron sputtering, vacuum evaporation, thermal evaporation, SILAR, molecular beam epitaxy, and electrodeposition, several researchers have reported success in producing thin films (Samuel \u003cem\u003eet al.,\u003c/em\u003e 2023; Ojegu \u003cem\u003eet al.,\u003c/em\u003e 2024; Yang \u003cem\u003eet al.,\u003c/em\u003e 2021; Hamada \u003cem\u003eet al.,\u003c/em\u003e 2021; Singh \u003cem\u003eet al.,\u003c/em\u003e 2020). Since the electro-spray deposition technique has relative benefits over other methods in terms of economy, convenience, and the capacity to evenly deposit large regions of films, ZrS and ZrS/Gd materials were deposited at room temperature in the current experiment. It is frequently utilized with electrically conductive materials, including conductive metals, alloys, and polymers, and it is widely used to deposit various metal chalcogenides. By controlling the rate at which precipitates emerge from the solution, homogeneous deposits are created on the substrate's surface. Adjusting the solution spray's temperature, deposition voltage, concentration, and other parameters also enables straightforward control over the film's thickness, rate of deposition, and quality.\u003c/p\u003e\n\u003cp\u003eDopants are known to try to alter the electrical, optical, and electronic characteristics of semiconducting materials (Ikhioya \u003cem\u003eet al.,\u003c/em\u003e 2021; Shaka \u003cem\u003eet al.,\u003c/em\u003e 2024; Ikhioya \u003cem\u003eet al.,\u003c/em\u003e 2020; Ikhioya \u003cem\u003eet al.,\u003c/em\u003e 2020). To boost the material's conductivity by decreasing the energy required for electrons to move from the valence band to the conduction band, gadolinium (Gd) was employed as a dopant. The results of the study offer materials that can be applied to photonic and optoelectronic applications.\u003c/p\u003e\n\u003cp\u003eThe advancement of photonics and optoelectronics depends significantly on the development of high-performance thin films with excellent electrical conductivity. Chalcogenide nanoparticle thin films, especially those based on zirconium sulphide (ZrS) doped with gadolinium (Gd), have emerged as promising materials due to their distinct electronic and optical characteristics. However, optimizing electrical conductivity in electro-sprayed chalcogenide films remains a major challenge. This difficulty stems from inconsistencies in the deposition process, uneven nanoparticle distribution, and morphological defects that hinder effective charge transport. To overcome these issues, a comprehensive investigation into the electrical conductivity of ZrS/Gd thin films is essential. This involves systematic experimental approaches that include fine-tuning electro-spraying parameters, employing advanced material characterization methods, and applying post-deposition treatments aimed at improving charge mobility. Enhancing factors such as spray rate, precursor concentration, applied voltage, and precursor temperature can lead to significant improvements in conductivity, thereby increasing the films' suitability for advanced photonic and optoelectronic devices.\u003c/p\u003e"},{"header":"2.0 Materials","content":"\u003cp\u003eThe following materials were used in the deposition and characterization of Zirconium Sulphide doped with Gadolinium (ZrS/Gd) thin films: distilled water, hydrochloric acid (HCl), Zirconium (IV) oxychloride octahydrate (ZrOCl\u003csub\u003e2\u003c/sub\u003e.8H\u003csub\u003e2\u003c/sub\u003eO), Gadolinium Oxide (Gd\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e), Thioacetamide (C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eNS), \u0026nbsp;Power source, heating mantle, substrate made of fluorine-doped tin oxide (FTO), \u0026nbsp;An electronic scale, \u0026nbsp;digital handheld pH meter (HL7300) 7.0. \u0026nbsp;Stopwatch, digital multimeter, ammeter, magnetic stirrer, thermometer (0-500oC), \u0026nbsp;Bruker D8 Advance X-ray diffractometer with Cu-Kα line (λ = 1.54056 Å) in 2θ range from 10° to 90°, UV-1800 Visible Spectrophotometer, Electrostatic Spray Atomization, Four Point Probe (Model T345), and Scanning Electron Microscopy.\u003c/p\u003e"},{"header":"3.0 Method","content":"\u003cp\u003eIn this study, the Electrostatic Spray Deposition (ESD) technique was employed. \u0026nbsp;It describes the use of an external force, an electric field, to split droplets. \u0026nbsp;Jets of various shapes emerged from the meniscus at the nozzle when a strong enough electric field force was applied to the ZrS/Gd solution. \u0026nbsp;To fragment into smaller droplets, the charged liquids or solutions experienced nonuniform fission and ellipsoidal deformation. \u0026nbsp;As a microfluidic technology, electrostatic spray is a potent instrument that can be precisely controlled by adjusting fluidic materials according to certain criteria. \u0026nbsp;Distilled water, a source of the anion (thioacetamide, C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eNS), and a source of the cation (zirconium (IV) oxychloride octahydrate, ZrOCl\u003csub\u003e2\u003c/sub\u003e.8H\u003csub\u003e2\u003c/sub\u003eO) make up the electrostatic spray system. An electric field containing the solutions to the fluorine-doped tin oxide (FTO) substrate was produced by the power supply. \u0026nbsp;Finally, using the electrostatic spray deposition technique, thin compounds were uniformly deposited.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.1 Substrate Cleaning Procedure\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConducting glasses were used as the substrate. The substrates were soaked in methanol and acetone, rinsed with distilled water, and then ultrasonically sonicated for half an hour in an acetone solution. They were then washed with purified water and left in an oven to dry.\u003c/p\u003e"},{"header":"4.0 Results","content":"\u003cp\u003e\u003cstrong\u003e4.1 Optical Study of ZrS and ZrS/Gd Material Deposited at Different Deposition Voltages\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePlots of the absorbance, transmittance, and reflectance of gadolinium-doped ZrS and undoped ZrS are shown in Figure 2 for various deposition voltages of 10.5V, 11.0V, and 11.5V. The graph (Figure 2a) shows the changing absorbance of ZrS/Gd at different wavelengths with\u0026ensp;various voltages (Pristine, 10.5V, 11V, and 11.5V). The absorbance intensity increases with transmitted voltage; more obviously, a sharp peak appears\u0026ensp;in the UV region (about 350-400 nm). This indicates that the larger voltage can improve the optical ability and the optoelectronic ability of the material, which can be attributed to strengthening the electronic transitions or\u0026ensp;adjusting the band structure. Beyond 400 nm, the absorbance gradually decreases, indicating a shift towards greater transparency in the visible and near-infrared regions. This behaviour highlights the influence of external voltage on the optical properties of ZrS/Gd, which may be useful for tunable optoelectronic applications (Anslem \u003cem\u003eet al.,\u003c/em\u003e 2023).\u003c/p\u003e\n\u003cp\u003eFigure 2b shows the UV-Vis reflectance spectra of ZrS/Gd at different applied voltages. From the graph, there is a strong reflectance peak at 300\u0026ndash;400 nm, and there is an increase in reflectance across the board with higher voltages. This shows that higher voltages influence the optical property of ZrS/Gd, perhaps changing its electronic structure or surface interaction. Trends in these observations are significant in optoelectronic and photonic device applications (Ojegu \u003cem\u003eet al.,\u003c/em\u003e 2024).\u003c/p\u003e\n\u003cp\u003eFigure 2c illustrates UV transmittance changes with wavelength under different voltages applied to ZrS/Gd. The pristine sample of ZrS has transmittance across the entire wavelength range, proving that it captures more of the UV light than the voltage-applied samples. Transmittance increases upon increasing the applied voltage (10.5V, 11V, and 11.5V) and is particularly high in the visible and near-infrared range. A very sharp fall in transmittance between about 250-400 nm is indicative of strong UV absorption. Beyond this range, the transmittance increases, with the 10.5V sample having the maximum transparency. This trend shows that higher voltage increases the optical properties of ZrS/Gd, which results in greater transparency in visible and near infrared, thus having an application in optoelectronic devices, sensors, and UV shield materials (Samuel \u003cem\u003eet al.,\u003c/em\u003e 2023).\u003c/p\u003e\n\u003cp\u003eThe energy band gap of ZrS/Gd at various applied voltages can be found using the Tauc plot in Figure 3(a) above. The approximate band gap energies for each sample condition are shown vertically by the dotted lines. The plot revealed the following energy band gaps: pristine: 3.19 eV, 3.21 eV at 10.5V, 3.31 eV at 11V, 3.62 eV at 11.5V. The energy band gap increased with applied voltage. This can be explained by changes in the material\u0026apos;s electrical structure when exposed to an external electric field, charge redistribution, or quantum confinement effects. These findings revealed that ZrS/Gd is a potential material for application in photodetectors, multi-colour LEDs, display technologies, high-speed optical communication systems, etc., because of its voltage-tunable band gap (Okechukwua \u003cem\u003eet al.,\u003c/em\u003e 2024).\u003c/p\u003e\n\u003cp\u003eThe optical conductivity in Figure 3(b) increases with energy, reaching a peak around 3.5\u0026ndash;4.0 eV, followed by a decline. The pristine ZrS exhibits lower optical conductivity compared to the doped samples. The optical conductivity increases as the doping voltage increases, with ZrS/Gd at 11.5V showing the highest peak, indicating enhanced conductivity. This shows that Gd doping significantly impacts the electronic and optical properties of ZrS, increasing its optical conductivity, particularly at higher doping voltages. The observed enhancement in optical conductivity of Gd-doped ZrS shows several potential applications in advanced optoelectronic and photonic devices such as photodetectors, solar cells, transparent conductive films, and optical sensors (Othmane \u003cem\u003eet al.,\u003c/em\u003e 2025).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe refractive index in Figure 3(c) remains relatively low at lower energy values but increases significantly between 3 eV and 4 eV, where strong optical transitions occur. The pristine ZrS shows a moderate refractive index, while the Gd-doped ZrS at 10.5V has the lowest values, indicating that this voltage reduces optical response. As the voltage increases to 11V, the refractive index rises, surpassing the pristine sample, indicating enhanced optical properties. At 11.5V, the refractive index reaches its peak, showing that higher voltages significantly influence the material\u0026apos;s optical behaviour, possibly due to charge redistribution, band structure modifications, or increased carrier concentration. The nonlinear trend implies that voltage-controlled tuning of the refractive index in ZrS/Gd could be useful for optoelectronic applications such as modulators, electro-optic modulators, optical sensors, etc. (Ikhioya \u003cem\u003eet al.,\u003c/em\u003e 2024)\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.2 \u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eThe Resistivity and Conductivity Study of ZrS and Gadolinium Doped Zirconium \u0026nbsp; \u0026nbsp; Sulphide (ZrS/Gd)\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe table below presents the electrical characteristics of ZrS/Gd films under various voltages. It investigates voltage-dependent changes in conductivity and mobility.\u003c/p\u003e\n\u003cp\u003eTable 1: Electrical Properties of Zirconium Sulphide (ZrS) Doped Gadolinium (ZrS/Gd) at Various Deposition Voltages for Photonic-Optoelectronic Applications.\u003c/p\u003e\n\u003cdiv align=\"Left\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSamples\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eThickness (nm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eResistivity (\u0026Omega;.m)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eConductivity (S/m)\u003csup\u003e-1\u003c/sup\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003eZrS (Pristine)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e101.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e0.60584371\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e1.65059071\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003eZrS/Gd 10.5V\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e107.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e0.57340386\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e1.743971516\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003eZrS/Gd 11.0V\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e109.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e0.565946144\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e1.766952581\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003eZrS/Gd 11.5V\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e113.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e0.546234088\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25%;\"\u003e\n \u003cp\u003e1.830716944\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eFrom the graph in Figure 4(a), it was observed that as the thickness increases from approximately 102 nm to 112 nm, resistivity decreases, indicating that thicker films have lower resistance to electrical current. Conversely, conductivity increases, confirming that thicker films facilitate better electrical conduction. This inverse relationship between resistivity and conductivity is expected, as conductivity is the reciprocal of resistivity. The trend confirms that as the deposition layer becomes thicker, its electrical properties improve due to reduced scattering effects or enhanced material uniformity. The observed trend in the graph, where increasing thickness leads to lower resistivity and higher conductivity, has several practical applications in optoelectronics (Shaka \u003cem\u003eet al.,\u003c/em\u003e 2024).\u003c/p\u003e\n\u003cp\u003eFigure 4(b) illustrates that as the deposition voltage increases from approximately 10.5V to 11.5V, resistivity decreases, while conductivity increases. This inverse relationship aligns with the fundamental principle that conductivity is the reciprocal of resistivity. The trend confirms that higher deposition voltage enhances the film\u0026apos;s electrical properties, due to improved material density, fewer defects, or better crystal structure, leading to lower resistive losses and improved electron mobility. This behaviour is crucial in applications like thin-film coatings, electronic devices, and conductive materials, where optimizing deposition parameters can significantly impact performance (Anslem \u003cem\u003eet al.,\u003c/em\u003e 2023).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.3\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eZrS and Gadolinium Doped Zirconium Sulphide (ZrS/Gd) Structural Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe table below outlines XRD diffraction patterns of ZrS/Gd films deposited with different voltages, indicating changes in structural properties.\u003c/p\u003e\n\u003cp\u003eTable 2: ZrS/Gd XRD Result for Voltage Variations\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"713\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSample\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e2\u0026theta; (degrees)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpacing d\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(\u0026Aring;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLattice\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eConstant a (\u0026Aring;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFWHM (\u0026deg;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCrystalline\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eSize D (nm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDislocation\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eDensity (1/nm\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eZrS Pristine\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.2839969\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.5575E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0343\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3156101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55737E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0686\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3472975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55725E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eZrS/Gd 10.5V\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.2839969\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.5575E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0343\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3156101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55737E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0686\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3472975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55725E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eZrS/Gd 11.0V\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.2839969\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.5575E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0343\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3156101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55737E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0686\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3472975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55725E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eZrS/Gd 11.5V\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.901497522\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.2839969\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.5575E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0343\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.88811063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3156101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55737E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17.1348%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.97191%;\"\u003e\n \u003cp\u003e15.0686\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14.3258%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.1685%;\"\u003e\n \u003cp\u003e5.874784858\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13.764%;\"\u003e\n \u003cp\u003e801.3472975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8708%;\"\u003e\n \u003cp\u003e1.55725E-06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eThe X-ray diffraction (XRD) pattern in Figure (5) illustrates the structural characteristics of ZrS doped with Gd under varying applied voltages: pristine, 10.5 V, 11.0 V, and 11.5 V. All the samples exhibit distinct diffraction peaks indexed to the (111), (112), (200), and (211) planes, confirming a polycrystalline nature. The pristine ZrS sample shows sharp and intense peaks, particularly the (111) reflection around 2\u0026theta; \u0026asymp; 28\u0026deg;, indicating high crystallinity. Upon application of 10.5 V, the intensity of all peaks decreases slightly, though the positions remain consistent, implying minor structural distortions or grain boundary modifications. At 11.0 V, peak intensities reduce further, particularly for the (111) and (200) planes, and there is slight broadening, indicating increased lattice strain or reduced crystallite size. At 11.5 V, the diffraction peaks are weakest and broadest, particularly for the (111) and (211) planes, indicating more significant disorder, defect formation, or potential amorphization due to the higher applied voltage. These variations in peak intensity and sharpness demonstrate that increasing the applied voltage during synthesis or fabrication alters the crystallinity and microstructure of ZrS/Gd materials (Ojegu \u003cem\u003eet al.,\u003c/em\u003e 2024). Table 2 includes additional characteristics and the crystallite size of the films, in addition to the computed crystallite or grain sizes, dislocation density, and dopant molarity for the films deposited at various gadolinium dopants were estimated using equations (1\u0026ndash;4)\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cimg src=\"data:image/png;base64,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\"\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003e4.4 \u0026nbsp;SEM Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe micrograph of ZrS and gadolinium-doped zirconium sulphide (ZrS/Gd) in Figure 6 demonstrates agglomeration on the films with no pinholes and a big grain size, or nanoparticles. The ZrS surface morphology is Clove-like, with precipitate visible in the ZrS micrograph; photon absorption is visible, but pinholes are absent due to the substrate\u0026apos;s huge grain size. The surface micrograph of the films under study shows that the addition of gadolinium as a dopant significantly changed the ZrS precursor. The surface morphology of the film showed a precipitate that resembled clouds. As the dopant voltage increased, the cloudlike precipitate for the material deposited at 11V gradually cleared out, creating a dense cloud in one spot on the surface. The doped ZrS material showed consistent nanoparticle deposition throughout the whole substrate for optoelectronic-photonic applications. Because the surface micrograph of the gadolinium-doped films is well-structured on the surface of the FTO substrate used for the synthesis, with no cracks or lattice strain, they will be a formidable contender for optoelectronic-photonic and other applications in the electronics and communication sectors (Samuel \u003cem\u003eet al.,\u003c/em\u003e 2023). \u003c/p\u003e"},{"header":"5.0 Conclusion","content":"\u003cp\u003eThis research has demonstrated that Gd-doped ZrS thin films fabricated through electro-spray deposition at varying voltages exhibit considerable enhancement in their optoelectronic and structural properties. Increasing the deposition voltage resulted in improved optical absorption, with maximum absorbance observed at 11.5 V and a progressive decrease in bandgap from 3.62 eV to 3.19 eV, favoring broader photon interaction. Electrical measurements confirmed an increase in conductivity from 1.65 S/m to 1.89 S/m and a reduction in resistivity from 0.61 Ω·m to 0.53 Ω·m as voltage increased, demonstrating improved charge carrier transport. XRD results indicated an enhancement in crystallite size and a decrease in dislocation density, while SEM analysis revealed uniform film morphology without defects. Collectively, these enhancements highlight the influence of applied voltage and silver doping on the functional properties of ZrS, establishing the films as viable materials for next-generation optoelectronic devices.\u003c/p\u003e"},{"header":" References","content":"\u003col\u003e\n \u003cli\u003eAgbo, P. E., and Nwofe, P. A. (2015). Comprehensive studies on the optical properties of ZnO-core shell thin films. \u003cem\u003eJ. Nanotechnol. Adv. Mater\u003c/em\u003e, \u003cem\u003e3\u003c/em\u003e(2), 63-97.\u003c/li\u003e\n \u003cli\u003eAslam, Z., Lone, A. R., Shoab, M., and Zulfequar, M. (2023). 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Transparent and conductive molybdenum-doped ZnO thin films via chemical vapor deposition. \u003cem\u003eACS Applied Electronic Materials\u003c/em\u003e, \u003cem\u003e2\u003c/em\u003e(1), 120-125.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","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":"","lastPublishedDoi":"10.21203/rs.3.rs-7195107/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7195107/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"In this study, Gd-doped zirconium sulphide (ZrS/Gd) thin films were successfully synthesized using an electro-spray deposition technique at varying deposition voltages of 10.5 V, 11.0 V, and 11.5 V, aimed at optimizing their structural, optical, and electrical properties for photonic and optoelectronic applications. UV–Vis spectroscopy revealed enhanced absorbance in the UV region (300–400 nm), with 0.75 a.u absorbance at 11.5 V, while transmittance peaked at ~85% for the 11.5 V sample in the visible range. The calculated optical bandgap values decreased from 3.62 eV at 11.5 V to 3.21 eV at 10.5 V, indicating improved photon absorption with increased voltage. Optical conductivity reached a maximum of 0.73 S/m at 11.5 V, and refractive index peaked at 3.0 around 3.4 eV photon energy. Electrical analysis showed enhanced conductivity, increasing from 1.65 S/m in the undoped ZrS to 1.89 S/m at 11.5 V, while resistivity dropped from 0.61 Ω·m to 0.53 Ω·m. XRD analysis confirmed improved crystallinity and reduced dislocation density at higher voltages, with crystallite size ranging from 178 nm to 200 nm. SEM micrographs revealed uniform film deposition and nanoparticle agglomeration with no pinholes. These findings show that Gd doping and voltage-controlled deposition significantly enhance the optoelectronic properties of ZrS thin films, making them promising candidates for optoelectronics and photonics devices.","manuscriptTitle":"Voltage-Driven Electro-Spray and Optoelectronic Evaluation of Gd-Doped Zirconium Sulphide Thin Films for Enhanced Optoelectronic Device Applications","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-25 06:41:39","doi":"10.21203/rs.3.rs-7195107/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":"25171faa-3d91-498a-a72d-92f8119a60e7","owner":[],"postedDate":"July 25th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":52048437,"name":"Physical sciences/Optics and photonics"},{"id":52048438,"name":"Physical sciences/Nanoscience and technology"}],"tags":[],"updatedAt":"2025-08-11T05:21:03+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-25 06:41:39","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7195107","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7195107","identity":"rs-7195107","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}