Liu Yi, Chen Jiajia, Zhang Jinfeng, Tang Zhongliang, Li Haibin, Yuan Jian
College of Physics and Electronic Information, Huaibei Normal University Huaibei Anhui 235000 P. R. China
Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Huaibei Normal University Huaibei Anhui 235000 P. R. China.
RSC Adv. 2020 Aug 18;10(51):30245-30253. doi: 10.1039/d0ra05712f. eCollection 2020 Aug 17.
The Z-scheme BiVO/Ag/AgS photocatalyst was fabricated a two-step route. The as-prepared samples were characterized by XRD, FE-SEM, HRTEM, XPS and UV-vis diffuse reflectance spectroscopy. The results of PL and photocurrent response tests demonstrate that the ternary BiVO/Ag/AgS composites had a high separation and migration efficiency of photoexcited carriers. As a result, the ternary photocatalyst exhibits enhanced photocatalytic activity for decomposing Rhodamine B (RhB) under LED light (420 nm) irradiation. The results of trapping experiments demonstrate both h and ˙OH play crucial roles in decomposing RhB molecules. Additionally, the energy band structures and density of states (DOS) of BiVO and AgS were investigated the density functional theory (DFT) method. Finally, a Z-scheme electron migration mechanism of BiVO → Ag → AgS was proposed based on the experimental and calculated results.
通过两步法制备了Z型BiVO/Ag/AgS光催化剂。采用X射线衍射（XRD）、场发射扫描电子显微镜（FE-SEM）、高分辨率透射电子显微镜（HRTEM）、X射线光电子能谱（XPS）和紫外-可见漫反射光谱对所制备的样品进行了表征。光致发光（PL）和光电流响应测试结果表明，三元BiVO/Ag/AgS复合材料具有较高的光生载流子分离和迁移效率。因此，该三元光催化剂在420nm发光二极管（LED）光照下对罗丹明B（RhB）的分解表现出增强的光催化活性。捕获实验结果表明，空穴（h）和羟基自由基（˙OH）在分解RhB分子过程中都起着关键作用。此外，采用密度泛函理论（DFT）方法研究了BiVO和AgS的能带结构和态密度（DOS）。最后，基于实验和计算结果，提出了BiVO→Ag→AgS的Z型电子迁移机制。
