Stepwise Photocatalytic Dissociation of Methanol and Water on TiO2(110)
Stepwise Photocatalytic Dissociation of Methanol and Water on TiO2(110)
复制标题
TiO2(110) 上甲醇和水的逐步光催化解离
DOI：
10.1021/ja304049x
复制
发表时间：
2012-08-15
影响因子：
15
通讯作者：
Yang, Xueming
中科院分区：
文献类型：
--
作者：
Guo, Qing;Xu, Chenbiao;Yang, Xueming
利用自行研制的氘代甲醇（CD_3OH）和H_2O在TiO_2（110）上的吸附实验装置，结合理论计算，研究了部分氘代甲醇（CD_3OH）和H_2O在TiO_2（110）上400 nm处的吸附行为。在TiO_2（110）表面上，CD_3OH的光催化分解过程是先O-H分解，然后C-D分解的分步过程。理论计算表明，高的C-D复合反向势垒和CD 2 O的易脱附使甲醇在TiO 2（110）上的光催化分解有效进行。理论计算结果还表明，H2O在TiO 2（110）上光催化分解后容易发生O-H复合的逆反应，从而抑制了光催化分解水的效率。
We have investigated the photocatalysis of partially deuterated methanol (CD3OH) and H2O on TiO2(110) at 400 nm using a newly developed photocatalysis apparatus in combination with theoretical calculations. Photocatalyzed products, CD2O on Ti-sc sites, and H and D atoms on bridge-bonded oxygen (BBO) sites from CD3OH have been clearly detected, while no evidence of H2O photocatalysis was found. The experimental results show that dissociation of CD3OH on TiO2(110) occurs in a stepwise manner in which the O-H dissociation proceeds first and is then followed by C-D dissociation. Theoretical calculations indicate that the high reverse barrier to C-D recombination and the facile desorption of CD2O make photocatalytic methanol dissociation on TiO2(110) proceed efficiently. Theoretical results also reveal that the reverse reactions, i.e, O-H recombination after H2O photocatalytic dissociation on TiO2(110), may occur easily, thus inhibiting efficient photocatalytic water splitting.