Song Xianyin, He Dong, Li Wenqing, Ke Zunjian, Liu Jiangchao, Tang Chongyang, Cheng Li, Jiang Changzhong, Wang Ziyu, Xiao Xiangheng
Department of Physics and Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Hubei Nuclear Solid Physics Key Laboratory, Wuhan University, Wuhan, 430072, P. R. China.
Institute of Technological Sciences, Wuhan University, Wuhan, 430072, P. R. China.
Angew Chem Int Ed Engl. 2019 Nov 11;58(46):16660-16667. doi: 10.1002/anie.201909934. Epub 2019 Oct 22.
An N-doped TiO model reveals a conceptually different mechanism for activating the N dopant based on delocalized orbital hybridization through O vacancy incorporation. Synchrotron-based X-ray absorption spectroscopy, time-resolved fluorescence, and DFT studies revealed that O vacancy incorporation can effectively stimulate the delocalization of N impurity states through p-band orbital modulation, which leads to a significant enhancement in photocarrier lifetime. Consequently, this effect also results in a remarkable increase in the incident photon-to-electron conversion efficiency in the range of 400-550 nm compared to that of conventional N-incorporated TiO (15 % versus 1 % at 450 nm). This work reveals the fundamental necessity of orbital modulation in the band engineering of metal oxides for driving solar water splitting and beyond.
一种氮掺杂的TiO模型揭示了一种基于通过引入氧空位进行离域轨道杂化来激活氮掺杂剂的概念上不同的机制。基于同步加速器的X射线吸收光谱、时间分辨荧光和密度泛函理论研究表明，引入氧空位可以通过p带轨道调制有效地刺激氮杂质态的离域，这导致光载流子寿命显著提高。因此，与传统的氮掺杂TiO相比，这种效应还导致在400 - 550 nm范围内的入射光子到电子转换效率显著提高（在450 nm时分别为15%和1%）。这项工作揭示了在金属氧化物的能带工程中进行轨道调制对于驱动太阳能水分解及其他应用的基本必要性。
