Aerosol Assisted Chemical Vapor Deposition of Cobalt-based Co-Catalysts on Bismuth Vanadate-based Photoelectrodes for Solar Water Splitting Systems

Aerosol Assisted Chemical Vapor Deposition of Cobalt-based Co-Catalysts on Bismuth Vanadate-based Photoelectrodes for Solar Water Splitting Systems | 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 Aerosol Assisted Chemical Vapor Deposition of Cobalt-based Co-Catalysts on Bismuth Vanadate-based Photoelectrodes for Solar Water Splitting Systems Andreas Kafizas, Mengyuan Huang, George Creasey, Zhipeng Lin, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7510016/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 18 Mar, 2026 Read the published version in NPG Asia Materials → Version 1 posted 9 You are reading this latest preprint version Abstract Cobalt phosphate (CoPi) is a widely used oxygen evolution reaction (OER) catalyst in photoelectrochemical (PEC) water splitting systems. Traditionally, CoPi is fabricated via photo-assisted electrodeposition (PED) from a cobalt-containing electrolyte solution, a method that is limited in scalability. In this study, we demonstrate a novel and scalable route to CoPi, where cobalt oxide (CoO x ) is first grown by aerosol-assisted chemical vapor deposition (AACVD) and then surface modified through a dark electrochemical treatment (ET) process. Both fabrication techniques were used to deposit CoPi onto bismuth vanadate (BiVO 4 ) photoanodes synthesised by AACVD. CoPi-decorated BiVO 4 fabricated via AACVD + ET demonstrated superior charge separation efficiency, stability over four hours of chronoamperometry, and photoelectrochemical performance, achieving an improved half-cell solar-to-hydrogen (HC-STH) efficiency of 1.16% at 1.23 V vs RHE compared to CoPi-decorated BiVO 4 fabricated by PED, which exhibited an HC-STH efficiency of 0.60%. These promising results highlight the potential of AACVD, conducted under atmospheric pressure, to enable the future development of both co-catalysts and scalable photoelectrode fabrication for large-area applications. Physical sciences/Chemistry/Materials chemistry/Optical materials Physical sciences/Materials science/Materials for energy and catalysis Physical sciences/Materials science/Nanoscale materials Full Text Additional Declarations There is no conflict of interest Supplementary Files SupportingInformation.docx Supporting Information Cite Share Download PDF Status: Published Journal Publication published 18 Mar, 2026 Read the published version in NPG Asia Materials → Version 1 posted Editorial decision: revise 02 Oct, 2025 Review # 2 received at journal 28 Sep, 2025 Review # 1 received at journal 18 Sep, 2025 Reviewer # 2 agreed at journal 07 Sep, 2025 Reviewer # 1 agreed at journal 04 Sep, 2025 Reviewers invited by journal 04 Sep, 2025 Submission checks completed at journal 03 Sep, 2025 Editor assigned by journal 01 Sep, 2025 First submitted to journal 01 Sep, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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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-7510016","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":510414075,"identity":"0e34db70-b9f0-4c16-9fca-f05f33589930","order_by":0,"name":"Andreas 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Traditionally, CoPi is fabricated \u003cem\u003evia\u003c/em\u003e photo-assisted electrodeposition (PED) from a cobalt-containing electrolyte solution, a method that is limited in scalability. In this study, we demonstrate a novel and scalable route to CoPi, where cobalt oxide (CoO\u003csub\u003ex\u003c/sub\u003e) is first grown by aerosol-assisted chemical vapor deposition (AACVD) and then surface modified through a dark electrochemical treatment (ET) process. Both fabrication techniques were used to deposit CoPi onto bismuth vanadate (BiVO\u003csub\u003e4\u003c/sub\u003e) photoanodes synthesised by AACVD. 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