Evolution of multiple spillover hydrogen species on anatase titanium dioxide
Date
2022-12-21
Journal Title
Journal ISSN
Volume Title
Publisher
Cell Reports Physical Science
Abstract
Hydrogen spillover is a widespread phenomenon on reducible metal oxide surfaces, with numerous observations confirming its occurrence. However, direct physical characterization of the spillover hydrogen species on an oxide catalyst support remains challenging. Differentiating the binding sites of specific spillover hydrogen species has been elusive. Herein, we vary temperature and reductive conditions, then quench and detect the physicochemical character of three distinct spillover hydrogen species on anatase titanium dioxide (TiO2-A) by deuterium magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, aided by density functional theory. Fast cooling during the sample preparation is crucial in quenching the spillover deuterium species to enable MAS NMR detection. Energetically favorable spillover deuterium species evolve from deuteron to deuteride states with increasing reduction temperature. Prevailing deuteron species reside on the 2-fold-coordinated O2c site of the TiO2-A (101) surface at low reduction temperature. At high reduction temperature, deuterides residing at oxygen vacancies (Ti6c–D–Ti5c) are formed.
Description
This article was originally published in Cell Reports Physical Science. The version of record is available at: https://doi.org/10.1016/j.xcrp.2022.101190
Keywords
hydrogen spillover, 2H MAS NMR, fast cooling, oxygen vacancy, hydride species, Anatase titanium oxide
Citation
Liu, Kairui, Guangjin Hou, Pan Gao, Xuezhong Nie, Shi Bai, Michael J. Janik, and Z. Conrad Zhang. “Evolution of Multiple Spillover Hydrogen Species on Anatase Titanium Dioxide.” Cell Reports Physical Science 3, no. 12 (December 21, 2022): 101190. https://doi.org/10.1016/j.xcrp.2022.101190.