Eur. Phys. J. D (2013) 67: 137
https://doi.org/10.1140/epjd/e2013-40007-8

Regular Article

Hydrogen adsorption and dissociation on small Al_nAu clusters: an electronic structure density functional study

¹ School of Chemistry and Material Science, Shanxi Normal University, Linfen 041004, P.R. China
² School of Management Science and Engineering, Central University of Finance and Economics, Beijing 100081, P.R. China

^a e-mail: gl-guoling@163.com

Received: 3 January 2013
Received in final form: 7 March 2013
Published online: 11 July 2013

Abstract

We present density functional calculations of H₂ adsorption and dissociation on small-sized Al_nAu clusters for n = 1−13. The growth pattern for Al_nAu (n = 2−5,7,12,13) clusters is Au atom occupying a peripheral position of Al_n clusters. And the growth pattern for Al_nAu (n = 6 and 10) clusters is Au-substituted Al_n+1 clusters. It is found that the Au atom substituted the surface atom of Al_n+1 cluster and occupies a peripheral position. H₂ is easily physically absorbed on the top Au atom of Al_nAu clusters with an end-on orientation rather than side-on orientation because of the more effective orbital overlap in the end-on orientation. The reaction of Al_nAu with H₂ would produce Al_nAuH₂ because of large exothermic energy changes and relatively small activation energies especially for Al₃Au and Al₇Au, which might serve as highly efficient and low-cost catalysts for hydrogen dissociation.