Synergistic effect of oxygen vacancy defects and TiO2/WO3 heterostructures in photocatalytic hydrogen production and dye degradation

Abstract

The exploration of cost-effective and efficient photocatalysts for environmental remediation and hydrogen production is a topic of immense importance in contemporary research. Titanium dioxide (TiO2) has been extensively researched in the area of environmental and energy photocatalysis due to its outstanding photocatalytic activity. However, its high photogenerated carrier recombination rate and wide bandgap limit the application. In this work, a TiO2/WO3 heterostructure nanocomposite with oxygen vacancy defects was synthesized through a simple sol-gel method. The introduction of oxygen vacancies reduced the bandgap and expanded the light absorption range, while the TiO2/WO3 heterostructure increased the photogenerated carriers and facilitated their separation. The resulting TiO2/WO3 nanocomposites exhibited enhanced photocatalytic activity, producing 101.88 μmol of hydrogen in 2 h for 100 mg of the nanocomposites, while the reaction constant for degrading dyes reached 0.1414 min−1. Moreover, the nanocomposites showed excellent stability under sunlight. This exploration provides a novel approach for designing and preparing TiO2-based composite photocatalysts.