Luo Zhibo, Wang Zhijie, Li Jia, Yang Kang, Zhou Gang
School of Science, Hubei University of Technology, Wuhan 430068, People's Republic of China.
Phys Chem Chem Phys. 2020 May 28;22(20):11392-11399. doi: 10.1039/d0cp00929f. Epub 2020 May 6.
We propose a universal dimer-doping strategy to improve the photocatalytic water splitting activity of Ru/TiO single-atom catalysts, in which the N atom is simultaneously doped. First-principles calculations show that the N dopants promote the substitution of Ti with Ru on the anatase TiO(101) surface by chemical bonding between Ru and N, and increase the stability of the system. Isolated Ru atoms act as active sites for the reduction of protons, and Ru-N/TiO has a hydrogen evolution activity comparable to that of Pd. The impurity bands within the band gap lead to a significant red-shift of the absorption edge towards the visible region, improving the photoabsorption and photocatalytic performance of TiO under sunlight. The reason is the charge compensation effect localized to the doped Ru-N dimers. We expect that this generic scheme that simultaneously realizes band-structure tailoring and reaction control also applies to other single-atom loaded oxide-based photocatalytic systems.
我们提出了一种通用的二聚体掺杂策略，以提高Ru/TiO单原子催化剂的光催化水分解活性，其中同时掺杂了N原子。第一性原理计算表明，N掺杂剂通过Ru与N之间的化学键促进了锐钛矿型TiO(101)表面上Ti被Ru的取代，并提高了体系的稳定性。孤立的Ru原子作为质子还原的活性位点，Ru-N/TiO具有与Pd相当的析氢活性。带隙内的杂质带导致吸收边缘向可见光区域显著红移，提高了TiO在阳光下的光吸收和光催化性能。原因是局限于掺杂的Ru-N二聚体的电荷补偿效应。我们期望这种同时实现能带结构剪裁和反应控制的通用方案也适用于其他负载单原子的氧化物基光催化体系。
