Heterostructured Ternary In2O3−Ag−TiO2 Nanotube Arrays for Simulated Sunlight‐Driven Photoelectrocatalytic Hydrogen Generation

Abstract

Abstract The ternary In2O3−Ag−TiO2 composites based on anatase TiO2 nanotube arrays (TNTs) were synthesized to extend the light responsive region, enhance the visible light absorption, reduce the recombination rate of charge carriers and promote the efficiency of water splitting for H2 evolution. Highly ordered TNTs were first prepared by electrochemical anodization of Ti sheets. Ag nanoparticles with a diameter of about 20 nm were then uniformly deposited inside and on the orifice of the TNTs. In2O3 nanoparticles synthesized through a solvent‐thermal method were subsequently modified on the Ag−TNTs using an ultrasound‐assisted electrophoresis method. In2O3−Ag−TNTs composites exhibited enhanced visible light absorption and photocurrent when compared to binary Ag−TNTs and In2O3−TNTs. As a result, the optimal hydrogen generation rate using the In2O3−Ag−TNTs composite under visible light irradiation was 1.92 μmol cm−2 h−1, 5 times higher than that of the pure TNTs.

Keywords

• TiO2 nanotube arrays
• Ag nanoparticles
• In2O3 nanoparticles
• photoelectrocatalysis
• hydrogen production