Title

Kinetics of H2 Adsorption at the Metal–Support Interface of Au/TiO2 Catalysts Probed by Broad Background IR Absorbance

Document Type

Article

Publication Date

3-29-2021

Abstract

H2 adsorption on Au catalysts is weak and reversible, making it difficult to quantitatively study. We demonstrate H2 adsorption on Au/TiO2 catalysts results in electron transfer to the support, inducing shifts in the FTIR background. This broad background absorbance (BBA) signal is used to quantify H2 adsorption; adsorption equilibrium constants are comparable to volumetric adsorption measurements. H2 adsorption kinetics measured with the BBA show a lower Eapp value (23 kJ mol−1) for H2 adsorption 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 H2 adsorption at the Au/TiO2 interface.

Identifier

PMID: 33403732

DOI

10.1002/anie.202013359

Publisher

Wiley-VCH

ISSN

14337851

Publication Information

Angewandte Chemie - International Edition

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