Wu Lu, Lin Jin, Ren Linyuan, Li Qianni, Chi Xin, Luo Ling, Zhang Yuexing, Zeng Ming-Hua
Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, P. R. China.
College of Chemistry and Chemical Engineering, Dezhou University, Dezhou 253023, P. R. China.
Phys Chem Chem Phys. 2022 Jun 22;24(24):15091-15102. doi: 10.1039/d1cp04729a.
Different surface planes of various types of titanium dioxide (TiO) crystals have diverse catalysis effects on the splitting of HO and H and the electronic structures of the formed hydroxylated TiO vary significantly. A series of sixteen types of hydroxylated TiO surfaces containing two types of hydroxyls (OH1 and OH2) on four kinds of low index surfaces [(001), (100), (101), and (110)] of two types of crystals [anatase (A) and rutile (R)] are studied using first-principles density functional theory calculations. The catalyzed splitting of HO and H on the eight low index surfaces is compared using Gibbs free energy. The geometries and electronic structures including the total and partial density of states and the charge density distribution of the sixteen hydroxylated surfaces are systematically described. The electronic structures of R-101, R-001, A-110, A-100, and A-001 surfaces are more significantly influenced by hydroxylation than other surfaces and the effects of OH2 are larger than those of OH1. In particular, the band gap values decrease and a new electronic energy state appears in R-001-OH2 and A-100-OH2. A new electronic state appears in the middle of the bands of R-101 and A-110 surfaces upon hydroxylation. The electron spin balance at the edge of the conduction band minimum of A-001-OH2 is disturbed. This research can provide theoretical guidance for experimental researchers to design surface hydroxylated TiO materials with tunable electronic structures and high catalytic performance.
不同类型的二氧化钛（TiO）晶体的不同表面平面，对HO和H的分解具有不同的催化作用，且形成的羟基化TiO的电子结构也有显著差异。利用第一性原理密度泛函理论计算，研究了两种晶体[锐钛矿（A）和金红石（R）]的四种低指数表面[（001）、（100）、（101）和（110）]上包含两种羟基（OH1和OH2）的十六种类型的羟基化TiO表面。使用吉布斯自由能比较了八个低指数表面上HO和H的催化分解情况。系统地描述了十六种羟基化表面的几何结构和电子结构，包括态密度总和与分态密度以及电荷密度分布。R - 101、R - 001、A - 110、A - 100和A - 001表面的电子结构受羟基化的影响比其他表面更显著，且OH2的影响大于OH1。特别是，R - 001 - OH2和A - 100 - OH2的带隙值减小，并出现了新的电子能态。羟基化后，R - 101和A - 110表面的能带中间出现了新的电子态。A - 001 - OH2导带最小值边缘的电子自旋平衡受到干扰。该研究可为实验研究人员设计具有可调电子结构和高催化性能的表面羟基化TiO材料提供理论指导。
