Abstract:
Environmental pollution and energy shortages significantly had affected human health and social development. Improving the photogenerated carrier separation/transfer efficiency of semiconductors remained crucial for achieving efficient photoelectric conversion and effective pollution purification. Using tungsten hexachloride as the raw material, tungsten oxide nanowires (W
18O
49) were firstly prepared by solvothermal method. Subsequently, the W
18O
49 nanowires were ultrasonically dispersed with carbon nanotubes (CNTs) in an aqueous potassium bromide solution, which was then added dropwise into acetic acid containing bismuth nitrate. By employing one-step solution-phase method, a W
18O
49-CNT-BiOBr step-scheme material with oxygen vacancy modulation was synthesized via in-situ reaction at room temperature. This W
18O
49-CNT-BiOBr with plasmonic effects demonstrated significantly enhanced solar light absorption efficiency, photoelectric response capability, and photocatalytic activity for pollutant degradation, and displayed a certain level of self-powered photoelectric response capability. Within 20 min, the degradation rate of 20 mg/L Rhodamine B (RhB) achieved approximately 99.8% with 10 mg W
18O
49-CNT-BiOBr, which was notably superior to that of pure W
18O
49 (72.9%) and BiOBr (55.8%). Further studies revealed that the separation and transport efficiency of photogenerated carriers in W
18O
49-CNT-BiOBr was significantly enhanced, which were mainly related to the construction of W
18O
49-CNT-BiOBr heterostructure, the introduction of oxygen vacancy and their synergistic effects among the components. Additionally, the superoxide radicals generated in W
18O
49-CNT-BiOBr heterostructure played a crucial role in the photocatalytic degradation of RhB.