Charge Polarization at a Au-TiC Interface and the Generation of Highly Active and Selective Catalysts for the Low-Temperature Water-Gas Shift Reaction
Charge Polarization at a Au-TiC Interface and the Generation of Highly Active and Selective Catalysts for the Low-Temperature Water-Gas Shift Reaction
J.A. Rodriguez, P.J. Ramirez, G.G. Asara, F. Viñes, J. Evans, P. Liu, J.M. Ricart, F. Illas
Angew. Chem. Int. Ed., 53 (2014) 11270.
Energy derived from DFT calculations for the WGS reaction on clean TiC(001) and Au4/TiC(001). TS = transition state.
Au atoms in contact with TiC(001) undergo a significant charge polarization. The strong metal–support interactions make Au/TiC(001) an excellent catalyst for the low-temperature water–gas shift (WGS), with turnover frequencies orders of magnitude larger than those observed for conventional metal/oxide catalysts such as Cu/ZnO. DFT calculations indicate that the WGS reaction follows an associative mechanism with HOCO as a key intermediate, showing how the synergy of Au/TiC(001) and the charge polarization is at the hearth of the different catalytic activity of Au/TiC(001) compared to TiC(001).