Porous photocatalysts with large surface areas are more photoactive than compact solid counterparts, owing to their larger surface areas and porous structure, which enhance the adsorption and confinement of light, thus improving the reaction between pollutants and photocatalysts. This paper reports the mechanisms involved in the enhanced photocatalytic activity of two kinds of porous BiVO₄ catalysts, named p-BVO-1 and p-BVO-2, which are fabricated by a template-free and alcohol-hydrothermal method, respectively. Characterization, photoelectrochemical and optical measurements, reactive species detection, UV–vis, and XPS analyses were conducted. The results show that the introduction of oxygen vacancies and prolonging effect of light within the pore structure can enhance the photon response and charge separation and transfer, which help to elevate the photocatalytic performance. The simultaneous photocatalysis test of p-BVO-1 for methylene blue (MB) and Cr(VI) showed that the addition of Cr(VI) enhanced MB adsorption by forming an MB-Cr-MB complex, and MB promoted the photoreduction of Cr(VI) by scavenging h⁺ and ⋅O₂⁻, which may oxidize Cr(III) to Cr(VI). The results indicate that ⋅O₂⁻ and h⁺ are mainly deployed to degrade MB, while e⁻ reduces Cr(VI) ions, thereby favoring the separation of electron-hole pairs.

具有大表面积的多孔光催化剂比致密的固体对应物更具光活性，这是因为它们具有较大的表面积和多孔结构，从而增强了光的吸收和约束，从而改善了污染物与光催化剂之间的反应。本文报道了两种多孔BiVO ₄增强光催化活性的机理。分别通过无模板法和醇水热法制备的名为p-BVO-1和p-BVO-2的催化剂。进行了表征，光电化学和光学测量，反应物种检测，紫外可见和XPS分析。结果表明，在孔结构中引入氧空位和延长光的作用可以增强光子响应以及电荷的分离和转移，从而有助于提高光催化性能。p-BVO-1对亚甲基蓝（MB）和Cr（VI）的同时光催化测试表明，添加Cr（VI）通过形成MB-Cr-MB配合物增强了MB的吸附，MB促进了Cr的光还原。 （VI）通过清除ħ ⁺和⋅O ₂ ^-，可能会将Cr（III）氧化为Cr（VI）。结果表明，⋅O ₂ ^-和H ⁺主要部署到劣化MB，而ë ^-减少铬（VI）离子，从而有利于电子-空穴对分离。