Din Syed Taj Ud, Lee Hankyu, Yang Woochul
Department of Physics, Dongguk University, Seoul 04620, Korea.
Nanomaterials (Basel). 2022 Feb 24;12(5):767. doi: 10.3390/nano12050767.
In this study, we report the synthesis of a 3-dimensional (3D) hierarchical BiOCl/BiOI (BOC/BOI) heterostructure for the photocatalytic degradation of Rhodamine-B (RhB) dye and colorless Bisphenol-A (BPA) pollutant under visible light. The heterostructure was prepared using in situ solvothermal and calcination methods. BOC/BOI exhibits a 3D hierarchical structure constructed with thin nano-platelets. The photocatalytic performance of the BOC/BOI photocatalyst demonstrated that the degradation efficiencies of RhB and BPA were 97% and 92% after light illumination within 90 and 30 min, respectively. In comparison, bare BOC and BOI efficiencies were only 20% and 10% for RhB dye, respectively, and 2.3% and 37% for BPA aqueous pollutants, respectively. Moreover, radical trapping measurements indicated that O and OH radicals played prominent roles in RhB and BPA degradation into mineralization. Analysis of band structures and photochemical redox reactions of BOC/BOI revealed a Z-scheme charge transfer between BOC and BOI by an internal electric field formed at the interface. Therefore, the highly improved photocatalytic performance of the BOC/BOI heterostructure is attributed to the synergetic effects of large surface area, high visible-light absorption, and the enhanced separation and transport of photo-excited electron-hole pairs induced by the hierarchical and Z-scheme heterojunction of the BOC/BOI.
在本研究中，我们报道了一种三维（3D）分级BiOCl/BiOI（BOC/BOI）异质结构的合成，用于在可见光下光催化降解罗丹明B（RhB）染料和无色双酚A（BPA）污染物。该异质结构采用原位溶剂热法和煅烧法制备。BOC/BOI呈现出由薄纳米片构建的三维分级结构。BOC/BOI光催化剂的光催化性能表明，光照90分钟和30分钟后，RhB和BPA的降解效率分别为97%和92%。相比之下，裸BOC和BOI对RhB染料的降解效率分别仅为20%和10%，对BPA水溶液污染物的降解效率分别为2.3%和37%。此外，自由基捕获测量表明，O和OH自由基在RhB和BPA降解为矿化产物的过程中起主要作用。对BOC/BOI的能带结构和光化学氧化还原反应分析表明，BOC和BOI之间通过界面处形成的内电场进行Z型电荷转移。因此，BOC/BOI异质结构光催化性能的大幅提高归因于其大表面积、高可见光吸收以及由BOC/BOI的分级和Z型异质结诱导的光激发电子-空穴对分离和传输增强的协同效应。
