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Updated: Aug 13, 2025

Preparation and Use of Photocatalytically Active Segmented Ag|ZnO and Coaxial TiO2-Ag Nanowires Made by Templated Electrodeposition
Published on: May 2, 2014
Function-switchable metal/semiconductor junction enables efficient photocatalytic overall water splitting with
Daixing Wei1, Yubo Tan1, Yiqing Wang1
1International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Abstract:
A novel metal/semiconductor photocatalyst, Cu nanoparticles (NPs) modified TiO2 hollow spheres (Cu/TiO2), was designed for efficient photocatalytic overall water splitting (POWS) under both ultraviolet (UV) and visible (Vis) light. This Cu/TiO2 photocatalyst possesses excellent POWS performance under Vis light at the highest level among the reported TiO2-based photocatalysts. Interestingly, the metal/semiconductor junction formed between Cu and TiO2 enables controlled water-oxidation product selectivity (H2O2 or O2) via different reaction pathways regulated by irradiation wavelengths. Under UV light, the electrons excited in TiO2 are captured by Cu NPs through the Cu/TiO2 Schottky interface for H2 production, with the photoholes in TiO2 producing H2O2 through a two-electron process; whilst under Vis light, Cu NPs act as plasmon to inject hot electrons to TiO2 for H2 production, while O2 is produced by hot holes on Cu NPs via a four-electron process. This rational design of function-switchable metal/semiconductor junction may be helpful to understand the mechanisms for POWS with desired gas/liquid water-oxidation products.
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