Please use this identifier to cite or link to this item:
Title: Role of surface stoichiometry on the interfacial electron behavior at Ni/TiO2(0 0 1) interfaces
Authors: Pan, J. S.
Tao, Junguang
Chiam, Sing Yang
Huan, Alfred Cheng Hon
Keywords: DRNTU::Science
Issue Date: 2012
Series/Report no.: Materials chemistry and physics
Abstract: The interfacial properties of Ni clusters grown on the stoichiometric and reduced rutile TiO2(0 0 1) surfaces were investigated by means of X-ray photoelectron spectroscopy (XPS). The binding energies (BE's) of elements from both overlayers and substrates were found to be affected by the formation of interfacial dipole. Regardless of the TiO2 surface stoichiometry, the Ni 2p3/2 BE's move monotonically toward lower value with the increase of Ni thickness due to the cluster size effect. However, the Ni 2p3/2 BE shift is much smaller on reduced TiO2(0 0 1) surfaces compared to that on the annealed stoichiometric surface. For stoichiometric and lightly reduced TiO2 surfaces, O 1s BE's exhibit an unexpected upward shift with increasing Ni thickness below 2 Å, and then downward shift to lower BE's when the Ni thickness increases further. This opposite tendency is attributed to the insulator-to-metal transition. On heavily reduced surface, only monotonically downward shift of the O 1s BE's was observed with the increase of Ni thickness. The different behaviors are well elucidated by collective contributions of interfacial charge transfer and image charge effect.
DOI: 10.1016/j.matchemphys.2012.01.109
Rights: © 2012 Elsevier B.V.
Fulltext Permission: none
Fulltext Availability: No Fulltext
Appears in Collections:SPMS Journal Articles

Citations 50

Updated on Jan 19, 2023

Web of ScienceTM
Citations 20

Updated on Feb 4, 2023

Page view(s) 10

Updated on Feb 4, 2023

Google ScholarTM




Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.