Table of Contents
Journal of Catalysts
Volume 2013 (2013), Article ID 467846, 5 pages
http://dx.doi.org/10.1155/2013/467846
Research Article

Structure and Reverse Hydrogen Spillover in Mononuclear Au0 and AuI Complexes Bonded to Faujasite Zeolite: A Density Functional Study

Department of Physics, Girijananda Chowdhury Institute of Management and Technology, Hatkhowapara, Azara, Guwahati, Assam 781017, India

Received 31 January 2013; Revised 6 May 2013; Accepted 8 May 2013

Academic Editor: Jianqin Zhuang

Copyright © 2013 Ajanta Deka. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We have studied the structure of mononuclear gold supported on acidic form of faujasite zeolite in two oxidation states, namely, 0 and +1, using density functional theory. The binding of the gold monomer to the zeolite support is stronger in the oxidation state +1 than in the oxidation state 0. For the oxidation state 0, the hydrogenated clusters AuH/(2H)-FAU, AuH2/H-FAU generated by stepwise reverse hydrogen spillover from bridging OH groups of zeolite are energetically preferred over the Au/(3H)-FAU structure. Reverse hydrogen spillover of all the three acidic protons from the zeolite to the Au monomer did not lead to a stable structure. The calculated reverse hydrogen spillover energy per hydrogen atom for zeolite supported AuH and AuH2 clusters are −10.2 and −5.1 kJ/mol, respectively, in the oxidation state 0, while in the oxidation state +1 it is 20.9 kJ/mol for zeolite supported Au+H cluster.