GaN-coated III–V photoelectrocatalyst with oxide-free interface and ambipolar charge transport

GaN-coated III–V photoelectrocatalyst with oxide-free interface and ambipolar charge transport | 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 GaN-coated III–V photoelectrocatalyst with oxide-free interface and ambipolar charge transport Shu Hu, Haoqing Su, Sahar Shekarabi, Xiaohan Ma, Wentao Zhang, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9284700/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 III–V semiconductors are promising light absorbers for solar photochemical synthesis, but their surfaces tend to corrode and form defect-rich interphases under photochemical conditions. Here, we report a plasma-enhanced atomic layer deposition (ALD) GaN coating for InP(100), a model high-efficiency absorber, that forms an oxygen-nearly-free, atomically abrupt interface at low temperatures (<350°C). This coating reduces the population of deleterious surface states to below one-thousandth of those at a benchmark TiO2/InP interface. The resulting Pt/GaN/InP photocathode exhibits a barrier height of ~1.2 eV, delivering a ~0.82 V photovoltage, ~97% external quantum efficiency, and over 160 hours of stability in a pH 0 electrolyte. Additionally, the remaining states support ambipolar electron and hole transport through a ~10-nm-thick GaN layer, thereby facilitating photocatalytic H2 evolution and reversible redox-mediator oxidation. Our study demonstrates electronically benign and chemically robust III–V/liquid interfaces for efficient and stable photochemical charge separation and solar energy conversion, enabled by conformal, isotropic, acid-stable GaN coatings. Physical sciences/Materials science/Materials for energy and catalysis Physical sciences/Chemistry/Catalysis Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SIforAmbipolarGaN0331Submit.pdf Supplementary Figures, tables, and Notes 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-9284700","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":615743458,"identity":"6fd22e1a-945b-480e-89c8-27c39af6ef03","order_by":0,"name":"Shu 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