The adsorption and dissociation of multilayer CH_3OH on TiO_2(110)  

作　　者：Ruimin Wang Hongjun Fan 

机构地区：[1]State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics

出　　处：《Science China Chemistry》2015年第4期614-619,共6页中国科学（化学英文版）

基　　金：financially supported by National Natural Science Foundation of China(21173212);the Key Research Program of the Chinese Academy of Sciences

摘　　要：The adsorption and dissociation of CH3OH on TiO2 （110） were studied using density functional theory methods. Our results suggest that CH3OH molecules can adsorb up to 3/4 ML （1 ML=5.2× 10^14 molecules/cm2） coverage at five-coordinated titanium （Tisc） sites to form the first layer. In the second layer, the CH3OH is adsorbed at bridge-bonded oxygen, and from the third layer, the CH3OH molecules form a hydrogen-bonded network with each other. The theoretical results show that dissociation of multilayer adsorbed methanol to aldehyde occurs through a stepwise pathway, with easy O-H bond dissociation and rate-determining C-H bond dissociation. The dissociation barriers for 8 or 12 CH3OH molecules on TiO2 are higher than that for low coverage by 0.15-0.21 eV; this suggests that the dissociation of multilayer adsorbed CH3OH is harder.The adsorption and dissociation of CH3OH on TiO2(110) were studied using density functional theory methods. Our results suggest that CH3OH molecules can adsorb up to 3/4 ML(1 ML=5.2×1014 molecules/cm2) coverage at five-coordinated titanium(Ti5c) sites to form the first layer. In the second layer, the CH3OH is adsorbed at bridge-bonded oxygen, and from the third layer, the CH3OH molecules form a hydrogen-bonded network with each other. The theoretical results show that dissociation of multilayer adsorbed methanol to aldehyde occurs through a stepwise pathway, with easy O–H bond dissociation and rate-determining C–H bond dissociation. The dissociation barriers for 8 or 12 CH3OH molecules on TiO2 are higher than that for low coverage by 0.15–0.21 e V; this suggests that the dissociation of multilayer adsorbed CH3OH is harder.

关 键 词：ADSORPTION DISSOCIATION MULTILAYER CH3OH TIO2 

分 类 号：O614.411[理学—无机化学] O647.3[理学—化学]