A novel 2D/2D BiOBr/UMOFNs (ultrathin metal-organic framework nanosheets) direct Z-scheme photocatalyst was successfully synthesized by using a simple deposition-precipitation method. The photocatalytic performance was evaluated under light irradiation, which revealed that the 2D/2D BiOBr/UMOFNs Z-scheme photocatalyst exhibits higher photocatalytic degradation of phenol compared to pristine BiOBr and UMOFNs. A BiOBr/UMOFNs-40% (mass ratio for BiOBr and UMOFNs of 1:0.4) photocatalyst was found to show the best photocatalytic degradation efficiency and stability, reaching 99% phenol degradation under light irradiation of 270 min and maintaining 97% degradation after 5 recycling runs. Results obtained from a trapping experiment and EPR suggest that reactive •OH and O2•- play a major role in phenol degradation. PL and photocurrent results reveal that the excellent photocatalytic activity of the 2D/2D BiOBr/UMOFNs photocatalyst can be ascribed to the efficient separation of photogenerated electron-hole pairs through a direct Z-scheme system. This article provides a possible reference for designing Z-scheme photocatalysts by using MOFs and semiconductors for practical organic pollutant treatment.

中文翻译：

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新型二维/二维 BiOBr/UMOFNs 直接 Z 型光催化剂用于高效降解苯酚

采用简单的沉积-沉淀法成功合成了一种新型 2D/2D BiOBr/UMOFNs（超薄金属有机框架纳米片）直接 Z 型光催化剂。在光照射下对光催化性能进行了评估，结果表明，与原始 BiOBr 和 UMOFNs 相比，2D/2D BiOBr/UMOFNs Z 型光催化剂表现出更高的苯酚光催化降解性能。发现 BiOBr/UMOFNs-40%（BiOBr 和 UMOFNs 的质量比为 1:0.4）光催化剂显示出最佳的光催化降解效率和稳定性，在 270 分钟的光照射下达到 99% 的苯酚降解，并在 5 分钟后保持 97% 的降解。回收运行。从捕集实验和 EPR 获得的结果表明反应性•OH 和 O2•- 在苯酚降解中起主要作用。PL和光电流结果表明，2D/2D BiOBr/UMOFNs光催化剂的优异光催化活性可归因于通过直接Z方案系统有效分离光生电子-空穴对。本文为使用MOFs和半导体设计Z型光催化剂用于实际的有机污染物处理提供了可能的参考。