Electrodeposition of p-type Cu2O on n-type TiO2 nanosheet arrays for enhanced photoelectrochemical water splitting

作者：Lin Wang, Hai Yu, YaXin Wang, Miao Chun, QianQian Lei, Xin Yao, XiaoChen Yao, Xin Wei, Jianguo Lv, Yan Xue, Jingwen Zhang, Siwen Zhou, Dandan Qu · 发表于：Electrochemistry Communications · 年份：2025 · DOI：10.1016/j.elecom.2025.108009 · 被引用次数：9 · 研究领域：Copper-based nanomaterials and applications、Advanced Photocatalysis Techniques、ZnO doping and properties

This study synthesized p-type Cu 2 O using an electrodeposition method and firmly attached it to TiO 2 nanosheets based on fluorine-doped tin oxide (FTO) substrates, forming a dense film that serves directly as a photoanode for photoelectrochemical (PEC) water splitting. Characterization techniques such as XRD, SEM, XPS, and UV–Vis confirmed the successful deposition of Cu 2 O on the TiO 2 nanosheets, forming a p-n heterojunction structure. The incorporation of Cu 2 O effectively broadened the light absorption range of TiO 2 , with a cut-off wavelength red-shifting to 537 nm, enabling it to absorb more visible light. Photoelectrochemical tests showed that under illuminated unbiased conditions, the photocurrent density of Cu 2 O-TiO 2 reached 0.3 mA/cm 2 , which is 7.5 times that of TiO 2 . After applying a small bias (0.5 V), the photocurrent density further increased to 2.1 mA/cm 2 , 5.2 times that under unbiased conditions, indicating that the introduction of electricity effectively accelerated the separation efficiency of photo-generated carriers. The Cu₂O-TiO₂ heterojunction exhibited significantly higher photocurrent density (measured by LSV) and charge transfer efficiency (evaluated by EIS) than pure TiO₂. This research provides new insights for PEC water splitting technology and serves as a reference for designing high-performance photocatalysts.