Chae, Sang Youn Maeng, Jung Hun Joo, Oh-Shim Yu, Sungju Park, Eun Duck 2026-02-03T02:00:15Z 2026-02-03T02:00:15Z 2026-01-12 2026-03 0169-4332 https://pubs.kist.re.kr/handle/201004/154097 Gallium oxynitride (GaON) is an emerging semiconductor with tunable band structures and promising band positions for photoelectrochemical (PEC) water oxidation. Here, we report a bottom-up approach for the growth of GaON thin films on Ti substrates via e-beam evaporation of Ga2O3 followed by thermal nitridation under a controlled NH3 flow. This method yields wurtzite-phase GaON with a narrowed band gap (1.7–2.0 eV), ideally positioned for visible-light-driven water oxidation. Analysis of systematic variations in nitridation temperature and precursor thickness confirmed that the crystallinity, charge-carrier transport, and light absorption characteristics of GaON collectively determine its overall PEC performance, with optimum activity achieved at 700 °C and a Ga2O3 thickness of approximately 300 nm. These findings establish clear design principles for GaON-based photoanodes. English Elsevier BV Novel gallium oxynitride thin film photoanodes for photoelectrochemical water oxidation Article 10.1016/j.apsusc.2025.165544 1 Applied Surface Science, v.722 Applied Surface Science 722 N scie scopus 001642056000001 2-s2.0-105024455070 Chemistry, Physical Materials Science, Coatings & Films Physics, Applied Physics, Condensed Matter Chemistry Materials Science Physics Article CHARGE SEPARATION HYDROGEN EVOLUTION GAN KINETICS HEMATITE INSIGHT BIVO4 Gallium oxynitride Thin film Photoelectrochemical anode Water oxidation e -beam evaporation