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Multi‐method Analysis of the Metal/Electrolyte Interface: Scanning Force Microscopy (SFM), Quartz Microbalance Measurements (QMB), Fourier Transform Infrared Spectroscopy (FTIR) and Grazing Incidence X‐ray Diffractometry (GIXD) at a Polycrystalline Copper Electrode
Author(s) -
Kautek W.,
Geuß M.,
Sahre M.,
Zhao P.,
Mirwald S.
Publication year - 1997
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/(sici)1096-9918(199706)25:7/8<548::aid-sia269>3.0.co;2-b
Subject(s) - analytical chemistry (journal) , fourier transform infrared spectroscopy , amorphous solid , crystallite , electrolyte , copper , chemistry , oxide , quartz crystal microbalance , materials science , crystallography , electrode , chemical engineering , adsorption , organic chemistry , chromatography , engineering
The successful application of various in situ and ex situ analytical techniques has been demonstrated at the buried interface between a metal and an electrolyte. Scanning force microscopy (SFM), electrochemical quartz microbalance measurements (EQMB), grazing incidence x‐ray diffractometry (GIXD), Fourier transform infrared spectroscopy (FTIR) in the specular reflection absorption mode and electrochemical charge measurements proved complementary in the characterization of a polycrystalline copper electrode in alkaline 0.1 M sulphate, perchlorate, fluoride and chloride electrolyte contact at pH 12. The surface exhibited a mixture of Cu(111) and Cu(200) grains of the order of 100 nm. Repeated potential scanning in the double layer and passive oxide region, between ‐1.4 and +0.1 V MSE , resulted in a complete reorganization of the surface morphology but no detectable corrosion. The electrochemical exchange of H 2 O and OH − between the electrolyte and the oxide film took place reversibly in accordance with a solid‐state growth mechanism. The copper atoms were redeposited at crystallographically preferred sites, generating comparatively homogeneously oriented, narrow Cu(111)‐edged grain ridges of length 200 nm. In the Cu(I) potential range, the formation of several monolayers of amorphous Cu 2 O could be confirmed. Only after extended time periods in the Cu(II) oxide potential region, Cu 2 O recrystallized to a (111) phase accompanied by Cu 2 O(200) and Cu 2 O(110). In this region, one observed the formation of amorphous Cu(OH) 2 concurrent with further growth of Cu 2 O. Strong CuOH IR stretching bands excluded the existence of CuO. At corrosive potentials of +0.25 V MSE , high anodic currents and substantial mass losses led to an electropolished surface with isolated features of <300 nm width and <70 nm height.© 1997 John Wiley & Sons, Ltd.