Constructing a p–n heterojunction between Bi2WO6 and Co3O4 for enhanced photothermocatalytic degradation of toluene

Abstract

The indiscriminate release of volatile organic compounds (VOCs) has exacerbated environmental pollution. Photothermocatalysis, a low-cost, high-efficiency, and environmentally friendly method, has attracted significant attention for VOC removal. Herein, a series of flower-like Bi₂WO₆/Co₃O₄ heterojunction nanocomposites (Bi₂WO₆/Co₃O₄ FHNs) were synthesized for photothermocatalytic toluene oxidation. The catalytic activity of Bi₂WO₆/Co₃O₄ FHNs is superior to that of the single components Bi₂WO₆ and Co₃O₄, with a T₉₀ of toluene at 130 °C under light irradiation. The excellent catalytic activity and stability of Bi₂WO₆/Co₃O₄ FHNs are attributable to the distinctive heterojunction interface and the augmented photothermal synergistic effect. The establishment of the p–n heterojunction significantly modifies the electronic structure of the catalyst surface and increases the surface adsorbed oxygen content, which is favourable for the creation of active oxygen. Under light irradiation, the p–n heterojunction can enhance light absorption, charge generation, and light-to-heat conversion capabilities, further boosting the photothermocatalytic degradation performance of toluene. This research provides novel perspectives for exploring and developing high-performance photothermal catalysts for VOC degradation.