Wang Yachao, Liu Lingfang, Wei Yaxiong, Xu Xinsheng, Zhao Guofeng, Zhong Rui, Fu Cong
Anhui Basic Discipline Research Center for Clean Energy and Catalysis, Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China.
Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, School of Physics and Electronic Information, Anhui Normal University, Wuhu 241002, China.
ACS Appl Mater Interfaces. 2024 Sep 25;16(38):50879-50886. doi: 10.1021/acsami.4c11426. Epub 2024 Sep 13.
Photocatalytic HO production stands as a promising sustainable technology for chemical synthesis. However, rapid charge recombination and limited oxygen adsorption by photocatalysts often limit its efficiency. Herein, we demonstrate that the synergy of Ag and interfacial oxygen vacancies on TiO could overcome these challenges. The optimized Ag/TiO-50 photocatalyst achieved an impressive HO production rate of 12.9 mmol h g and maintained a steady-state concentration of 12.8 mM, significantly outperforming most TiO-based photocatalysts documented in the literature. Detailed mechanistic studies, aided by TAS, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) techniques, indicate that the oxygen vacancies at the Ag-TiO interface act as an interfacial hole trap, inducing a directional hole transfer. This, coupled with Ag acting as an electron acceptor, synergistically boosts the electron-hole separation. Additionally, the increased amount of oxygen vacancies at the Ag-TiO interface of Ag/TiO-50 leads to enhanced O adsorption, thus contributing to its superior catalytic performance. This study provides valuable insights into interfacial traps in the charge transfer process and highlights the potential of interface regulation for achieving efficient photocatalytic conversion.
光催化产生羟基自由基是一种很有前景的用于化学合成的可持续技术。然而，光催化剂中快速的电荷复合以及有限的氧吸附常常限制其效率。在此，我们证明了银与二氧化钛表面界面氧空位的协同作用能够克服这些挑战。优化后的Ag/TiO-50光催化剂实现了令人印象深刻的12.9 mmol h g的羟基自由基产生速率，并保持12.8 mM的稳态浓度，显著优于文献中报道的大多数二氧化钛基光催化剂。借助时间分辨吸收光谱（TAS）、X射线光电子能谱（XPS）和电子顺磁共振（EPR）技术进行的详细机理研究表明，Ag-TiO界面处的氧空位充当界面空穴陷阱，诱导定向空穴转移。这与作为电子受体的银协同作用，促进了电子-空穴分离。此外，Ag/TiO-50的Ag-TiO界面处增加的氧空位数量导致氧吸附增强，从而有助于其优异的催化性能。这项研究为电荷转移过程中的界面陷阱提供了有价值的见解，并突出了界面调控在实现高效光催化转化方面的潜力。
