A DFT study of molecular adsorption on titania-supported AuRh nanoalloys

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

External organisations

  • Université Claude Bernard

Abstract

AuRh/TiO2 nanocatalysts have proved their efficiency in several catalytic reactions. In this work, density functional theory calculations are performed to investigate the effect of the TiO2 support on the structures of fcc 38-atom and 79-atom AuRh nanoalloys and their adsorption properties towards the reactant molecules CO and O2. d-band centre analysis shows that the d-band model captures the trends better for both larger and supported alloy clusters due to reduced mechanical effects. Calculations reveal metal-to-support electron transfer, depending mainly on which metal atoms lie at the interface with the support. The adsorption strengths of CO and O2 molecules on experimentally-relevant Janus segregated structures are slightly lower than on pure Rh clusters, which may reduce poisoning effects, while maintaining the high reactivity of Rh. In addition, higher adsorption energies are predicted for the less stable AucoreRhshell structure, which may lead to adsorption-induced restructuring under reaction conditions.

Details

Original languageEnglish
Pages (from-to)142–151
Number of pages10
JournalComputational and Theoretical Chemistry
Volume1107
Early online date17 Feb 2017
Publication statusPublished - May 2017

Keywords

  • Adsorption properties, Alloying effects, Au-Rh, D-band centre, Nanoalloys, Support effects