Release Time:2019-03-09  Hits:

Indexed by: Journal Article

Date of Publication: 2015-01-25

Journal: JOURNAL OF MOLECULAR STRUCTURE

Included Journals: Scopus、SCIE、EI

Volume: 1080

Issue: 1080

Page Number: 105-110

ISSN: 0022-2860

Key Words: Pd-n clusters; Cluster size; Adsorption; Dissociation; Electronic properties

Abstract: The H-2 adsorption and dissociation on Pd-n (n = 4, 6, 13, 19, 55) clusters were studied with GGA-DFT. The heat releases decrease from 0.81, 0.67, 0.64 to 0.45 eV for the H-2 adsorbed on the Pd-n (n = 4, 6, 13, 19), and increase to 0.51 eV on the Pd-55. Energy barriers of the H-2 dissociation decrease from 0.41, 0.40 to 0.058 eV on the Pd-n (n = 4, 6, 13) and increase to 0.18 and 0.20 eV on the Pd-n (n = 19,55). Comparing the adsorption heats with energy barriers, the H-2 dissociation is energetically favorable. The Hirshfeld charge reveals that charge-transfer from Pd-n to H-2 increases upon adsorption-dissociation. The PDOS shows that the s-band of H-2 shifts toward Fermi level and d-band of the Pd-4-2H complexes is more delocalized upon H-2 dissociation. Present results show a structure sensitivity of the H-2 adsorption-dissociation on the Pd-n clusters due to inherent size changes. (C) 2014 Elsevier B.V. All rights reserved.