Kinetics and Dynamics of Photocatalyzed Dissociation of Ethanol on Ti02（110）  

乙醇在TiO2（110）表面光催化解离的动力学和超快电子动态学

作　　者：马志博[1] 周传耀[1] 毛新春[1] 任泽峰[1] 戴东旭[1] 杨学明[1] 

机构地区：[1]中国科学院大连化学物理研究所分子反应动力学国家重点实验室,大连116023

出　　处：《Chinese Journal of Chemical Physics》2013年第1期1-7,I0003,共8页化学物理学报（英文）

摘　　要：The kinetics and dynamics of photocatalyzed dissociation of ethanol on TiO2（110） sur- face have been studied using the time-dependent and time-resolved femtosecond two-photon photoemission spectroscopy respectively, in order to unravel the photochemical properties of ethanol on this prototypical metal oxide surface. By monitoring the time evolution of the photoinduced excited state which is associated with the photocatalyzed dissociation of ethanol on Ti5c sites of Ti02（ll0）, the fractal-like kinetics of this surface photocatalytic reaction has been obtgined. The measured photocatalytic dissociation rate on reduced TiO2（l10） is faster than that on the oxidized surface. This is attributed to the larger defect density on the reduced surface which lowers the reaction barrier of the photocatalytic reaction at least methodologically. Possible reasons associated with the defect electrons for the acceleration have been discussed. By performing the interferometric two-pulse corre- lation on ethanol/TiO2（l10） interface, the ultrafast electron dynamics of the excited state has been measured. The analyzed lifetime （24 fs） of the excited state is similar to that on methanol/TiO2（110）. The appearance of the excited state provides a channel to mediate the electron transfer between the TiO2 substrate and its environment. Therefore studying its ultrafast electron dynamics may lead to the understanding of the microscopic mechanism of photocatalysis and photoelectrochemical energy conversion on TiO2.

关 键 词：Two-photon photoemission PHOTOCATALYSIS TiO2 Kinetic Ultrafast dynamic 

分 类 号：O[理学]