Liu Yue, Zeng Xiangkang, Easton Christopher D, Li Qinye, Xia Yun, Yin Yichun, Hu Xiaoyi, Hu Jian, Xia Dehua, McCarthy David T, Deletic Ana, Sun Chenghua, Yu Jiaguo, Zhang Xiwang
Department of Chemical Engineering, Monash University, Clayton, VIC 3800, Australia.
Nanoscale. 2020 Apr 30;12(16):8775-8784. doi: 10.1039/d0nr01611j.
The face-to-face contact of a vertical heterojunction is beneficial to charge interaction in photocatalysis. However, constructing a vertical heterojunction with uncompromised redox ability still remains a challenge. Herein, we report the successful synthesis of a WO3-TiO2 vertical heterojunction via establishing an internal electric field across the interface. Experimental investigation and computational simulations reveal that strong electric coupling occurs at the WO3-TiO2 interface forming an internal electric field. The internal electric field induces a Z-scheme charge-carrier transfer through the heterojunction under light irradiation, which leads to effective charge separation and maintains high reaction potentials of charge-carriers. The improved photocatalytic activity of the WO3-TiO2 heterojunction is proved by enhanced generation of reactive oxygen species and accelerated Escherichia coli (E. coli) disinfection. This study provides new insights into understanding and designing Z-scheme heterogeneous photocatalysts.
垂直异质结的面对面接触有利于光催化中的电荷相互作用。然而，构建具有不降低的氧化还原能力的垂直异质结仍然是一个挑战。在此，我们报告通过在界面上建立内部电场成功合成了WO3-TiO2垂直异质结。实验研究和计算模拟表明，在WO3-TiO2界面处发生强电耦合，形成内部电场。内部电场在光照下通过异质结诱导Z型电荷载流子转移，这导致有效的电荷分离并保持电荷载流子的高反应电位。通过增强活性氧的产生和加速大肠杆菌消毒证明了WO3-TiO2异质结光催化活性的提高。这项研究为理解和设计Z型异质光催化剂提供了新的见解。
