Abstract Over the past few years, the emission of organic pollutants into the environment has increased tremendously. Therefore, various photocatalysts have been developed for the degradation of organic pollutants. In this study, a step-scheme BiVO4/Ag3VO4 composite was synthesized via a hydrothermal and chemical deposition process for the degradation of methylene blue.The composite showed strong redox ability under visible light. The 40%BiVO4/Ag3VO4 composite showed excellent photocatalytic degradation properties with a Kapp of 0.05588 min−1, which is 22.76 and 1.76 times higher than those of BiVO4 (0.00247 min−1) and Ag3VO4 (0.03167 min−1), respectively. The composite showed a stable performance and could retain 90% of its photocatalytic activity even after four cycles. The improved catalytic performance of the composite as compared to BiVO4 and Ag3VO4 can be attributed to its novel step-scheme mechanism, which facilitated the separation of the photogenerated charges and increased their lifetime. The photoluminescence measurement results and transient photocurrent response revealed that the composite showed efficient extraction of charge carriers.

中文翻译：

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一种新型步进式 BiVO4/Ag3VO4 光催化剂，可增强可见光照射下的光催化降解活性

摘要 近年来，向环境中排放的有机污染物急剧增加。因此，人们开发了各种光催化剂来降解有机污染物。在这项研究中，通过水热和化学沉积工艺合成了一种用于降解亚甲基蓝的阶梯式 BiVO4/Ag3VO4 复合材料。该复合材料在可见光下表现出很强的氧化还原能力。40%BiVO4/Ag3VO4 复合材料表现出优异的光催化降解性能，Kapp 值为 0.05588 min-1，分别是 BiVO4 (0.00247 min-1) 和 Ag3VO4 (0.03167 min-1) 的 22.76 倍和 1.76 倍。该复合材料表现出稳定的性能，即使在四次循环后仍能保持其 90% 的光催化活性。与 BiVO4 和 Ag3VO4 相比，复合材料的催化性能提高可归因于其新颖的步骤机制，这促进了光生电荷的分离并延长了它们的寿命。光致发光测量结果和瞬态光电流响应表明复合材料显示出有效的载流子提取。