Center for Interdisciplinary Molecular Science, Institute of Molecular Science, National Chiao Tung University, Hsinchu 300, Taiwan.
J Comput Chem. 2011 Apr 30;32(6):1065-81. doi: 10.1002/jcc.21686. Epub 2010 Nov 4.
This study investigates the adsorption and reactions of H(2)O(2) on TiO(2) anatase (101) and rutile (110) surfaces by first-principles calculations based on the density functional theory in conjunction with the projected augmented wave approach, using PW91, PBE, and revPBE functionals. Adsorption mechanisms of H(2)O(2) and its fragments on both surfaces are analyzed. It is found that H(2)O(2) , H(2)O, and HO preferentially adsorb at the Ti(5c) site, meanwhile HOO, O, and H preferentially adsorb at the (O(2c))(Ti(5c)), (Ti(5c))(2), and O(2c) sites, respectively. Potential energy profiles of the adsorption processes on both surfaces have been constructed using the nudged elastic band method. The two restructured surfaces, the 1/3 ML oxygen covered TiO(2) and the hydroxylated TiO(2), are produced with the H(2)O(2) dehydration and deoxidation, respectively. The formation of main products, H(2)O(g) and the 1/3 ML oxygen covered TiO(2) surface, is exothermic by 2.8 and 5.0 kcal/mol, requiring energy barriers of 0.8 and 1.1 kcal/mol on the rutile (110) and anatase (101) surface, respectively. The rate constants for the H(2)O(2) dehydration processes have been predicted to be 6.65 × 10(-27) T(4.38) exp(-0.14 kcal mol(-1)/RT) and 3.18 × 10(-23) T(5.60) exp(-2.92 kcal mol(-1)/RT) respectively, in units of cm(3) molecule(-1) s(-1).
本研究采用基于密度泛函理论的第一性原理计算，结合投影缀加波方法，使用 PW91、PBE 和 revPBE 泛函，研究了 H(2)O(2)在 TiO(2)锐钛矿（101）和金红石（110）表面的吸附和反应。分析了 H(2)O(2)及其碎片在两个表面上的吸附机制。结果表明，H(2)O(2)、H(2)O 和 HO 优先吸附在 Ti(5c)位，而 HOO、O 和 H 优先吸附在（O(2c))(Ti(5c))、(Ti(5c))(2)和 O(2c)位。使用 nudge 弹性带方法构建了两个表面上吸附过程的势能曲线。通过 H(2)O(2)脱水和脱氧，生成了两个重构表面，即 1/3 ML 氧覆盖的 TiO(2)和羟基化的 TiO(2)。主要产物 H(2)O(g)和 1/3 ML 氧覆盖的 TiO(2)表面的形成是放热的，分别为 2.8 和 5.0 kcal/mol，在金红石（110）和锐钛矿（101）表面上的能量势垒分别为 0.8 和 1.1 kcal/mol。预测 H(2)O(2)脱水过程的速率常数分别为 6.65×10(-27) T(4.38) exp(-0.14 kcal mol(-1)/RT)和 3.18×10(-23) T(5.60) exp(-2.92 kcal mol(-1)/RT)，单位为 cm(3) molecule(-1) s(-1)。
