Kinetics of H 2 Adsorption at the Metal–Support Interface of Au/TiO 2 Catalysts Probed by Broad Background IR Absorbance
Kinetics of H 2 Adsorption at the Metal–Support Interface of Au/TiO 2 Catalysts Probed by Broad Background IR Absorbance
复制标题
通过宽背景红外吸收探测 Au/TiO 2 催化剂金属-载体界面上的 H 2 吸附动力学
DOI：
10.1002/anie.202013359
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Chandler, Bert D.
中科院分区：
文献类型：
--
作者：
Mahdavi‐Shakib, Akbar;Kumar, K. B.;Whittaker, Todd N.;Xie, Tianze;Grabow, Lars C.;Rioux, Robert M.;Chandler, Bert D.
H2在Au催化剂上的吸附是弱的和可逆的，使得难以定量研究。我们证明了H2在Au/TiO 2催化剂上的吸附导致了电子转移到载体上，从而引起FTIR背景的位移。该宽背景吸光度（BBA）信号用于量化H2吸附;吸附平衡常数与容量吸附测量相当。用BBA测量的H2吸附动力学表明，H2吸附的Eapp值（23 kJ mol−1）比以前报道的代用H/D交换（33 kJ mol− 1）低。 我们还确定了一个以前未报道的H-O-H弯曲振动与质子吸附在电子上不同的Ti-OH金属支持界面网站，提供了新的见解的性质和动力学的H2吸附在Au/TiO 2界面。
H2adsorption on Au catalysts is weak and reversible, making it difficult to quantitatively study. We demonstrate H2adsorption on Au/TiO2catalysts results in electron transfer to the support, inducing shifts in the FTIR background. This broad background absorbance (BBA) signal is used to quantify H2adsorption; adsorption equilibrium constants are comparable to volumetric adsorption measurements. H2adsorption kinetics measured with the BBA show a lowerEappvalue (23 kJ mol−1) for H2adsorption than previously reported from proxy H/D exchange (33 kJ mol−1). We also identify a previously unreported H‐O‐H bending vibration associated with proton adsorption on electronically distinct Ti‐OH metal‐support interface sites, providing new insight into the nature and dynamics of H2adsorption at the Au/TiO2interface.