Solvothermal preparation of Bi/Bi2O3 nanoparticles on TiO2 NTs for the enhanced photoelectrocatalytic degradation of pollutants

Abstract

Bi/Bi2O3 nanoparticles were deposited on the surface of TiO2 nanotube arrays (TiO2 NTs) by a simple solvothermal method by changing the C6H12O6 concentration. The intimate interface contact of Bi2O3 and TiO2 NTs formed Z-scheme heterojunction with high visible-light response. The concomitant Bi0 not only accelerated charge carrier transfer, but also improved the visible light absorption by the local surface plasmon resonance (LSPR). The Z-scheme heterojunction Bi/Bi2O3/TiO2 NTs photocatalysts significantly improved the visible light absorption, photocurrent and photocatalytic activity. The visible light photocurrent density and photovoltage achieved 6.42 mA/cm2 and -0.35 V, and the photoelectrocatalytic removal efficiencies of MO and RhB dyes achieved 75% and 80%, respectively. The photocatalytic degradation mechanism was tentatively proposed based on the electron transfer path and photocatalytic data. The enhanced photoelectrochemical performance of Bi/Bi2O3/TiO2 NTs was ascribed to synergistic effect of Z-scheme heterojunction interface and LSPR effect of Bi0.