Please use this identifier to cite or link to this item: http://scholarbank.nus.edu.sg/handle/10635/76358
Title: In situ scanning tunneling microscopy investigation of restructuring and anodic dissolution of Cu( 111 ) electrode in sulphuric acid solution
Authors: Li, W.H.
Ye, J.H.
Li, S.F.Y. 
Nichols, R.J.
Keywords: Adatoms
Adsorption kinetics
Low index single crystal surfaces
Scanning tunneling microscopy
Single crystal surfaces
Surface structure, morphology, roughness, and topography
Tunneling
Issue Date: 20-Mar-2000
Source: Li, W.H.,Ye, J.H.,Li, S.F.Y.,Nichols, R.J. (2000-03-20). In situ scanning tunneling microscopy investigation of restructuring and anodic dissolution of Cu( 111 ) electrode in sulphuric acid solution. Surface Science 449 (1-3) : 207-217. ScholarBank@NUS Repository.
Abstract: In situ scanning tunneling microscopy (STM) has been employed to study the structures, dissolution/redeposition and anodic dissolution of Cu(111) surface in aqueous sulphuric acid on an atomic scale. A short-range periodicity resulting from the ordered (bi)sulphate adlayer and a long-range periodicity (Moiré pattern) have been observed, which is consistent with previous work. The Moiŕ pattern lying within ±117deg; to the close-packed {110} directions of the unreconstructed Cu(111) surface has been further determined here. We focus here on the anodic dissolution and restructuring of the surface in the presence of adsorbed (bi)sulphate. We are able to image the Moiré pattern of the (bi)sulphate covered surface during such dynamic processes and hence determine preferential etching and redeposition directions. It was found that step edges running along the Moiré pattern are most stable during such dynamic processes. The Moiré depressions are typically located at a fixed distance from the step edge. The Moire pattern does not run along the close-packed directions of the (bi)sulphate adlayer so the step reorientation on (bi)sulphate covered Cu(lll) is significantly different from the behaviour on the chloride covered surface, for which it has been reported previously that the steps orientated along close-packed Cl rows are stabilised. A different mechanism is suggested for the dissolution and redeposition kinetics on (bi)sulphate covered surfaces, in which the Moire pattern 'steers' the dissolution or growth directions. A spiral growth during Cu local redeposition originating from dislocations has also been observed and discussed. © 2000 Elsevier Science B.V. All rights reserved.
Source Title: Surface Science
URI: http://scholarbank.nus.edu.sg/handle/10635/76358
ISSN: 00396028
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

Page view(s)

32
checked on Jan 20, 2018

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.