A Bi-BiOBr/BiPO₄ heterojunction structure was successfully synthesized via a two-step solvothermal method with ethylene glycol as a reducer. Little BiPO₄ irregular polyhedrons and little metal Bi spherical nanoparticles were uniformly dispersed on the surface of BiOBr nanosheets with intimate contact and formed a heterojunction structure between BiPO₄ and BiOBr. It was found that Bi-BiOBr/BiPO₄ had a significant improvement in photocatalytic performance for RhB degradation compared to bare BiOBr and BiPO₄. The photocatalytic degradation rate constant of 0.2-Bi/BiOBr/BiPO₄ was 1.44 h^-1, which was 3.8 times and 14.2 times more than that of bare BiOBr and BiPO₄, respectively. This is attributed to the formation of a ternary heterojunction, which benefits the separation of photogenerated electron-hole pairs. Furthermore, with the introduction of metal Bi, the SPR effect of metal Bi can effectively improve the absorption ability of Bi-BiOBr/BiPO₄ photocatalyst, resulting in enhanced photoactivity. In this work, the mechanism of photocatalytic degradation was studied by using the photochemical technique and the capture experiment of active species, and it was revealed that h⁺ and ^⋅O₂^- played a major role in the photocatalytic process.

中文翻译：

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具有增强光催化活性的可见光响应 Bi-BiOBr/BiPO4 异质结构的简单制备

以乙二醇为还原剂，通过两步溶剂热法成功合成了Bi-BiOBr/BiPO ₄异质结结构。小BiPO ₄不规则多面体和小金属Bi球形纳米粒子均匀分散在BiOBr纳米片表面并紧密接触，在BiPO ₄和BiOBr之间形成异质结结构。发现与裸BiOBr和BiPO ₄相比，Bi-BiOBr/BiPO ₄在RhB降解的光催化性能方面具有显着改进。0.2-Bi/BiOBr/BiPO ₄的光催化降解速率常数为1.44 h ^-1，分别是裸BiOBr和BiPO的3.8倍和14.2倍₄、分别。这归因于三元异质结的形成，这有利于光生电子-空穴对的分离。此外，随着金属Bi的引入，金属Bi的SPR效应可以有效提高Bi-BiOBr/BiPO ₄光催化剂的吸收能力，从而增强光活性。在这项工作中，利用光化学技术和活性物种的捕获实验研究了光催化降解的机理，发现h ⁺和^· O ₂ ^-在光催化过程中起主要作用。