화학공학소재연구정보센터
Electrochimica Acta, Vol.52, No.11, 3660-3666, 2007
Electrochemical characterization of the underpotential deposition of tellurium on Au electrode
Electrochemical characterization of the underpotential deposition (UPD) of tellurium on Au substrate has been performed in this paper. The mechanism of Te deposition and its voltammetry dependence on the Te ion concentration were studied, and it suggests that variations in the metal ion concentration may affect the UPD process kinetics. The effect of tellurium adsorbates on UPD behavior of Te has also been investigated. The results show that the tellurium adsorbates could be irreversibly adsorbed upon the Au substrate surface under the open-circuit conditions. Subsequent removal of the Te adsorbates was also proved to be very difficult within the Au double-layer region, and a standard electrochemical cleaning procedure is necessary to remove the Te adsorbates completely. When the potential was cycled into the An oxidation region, a substantial loss of Te adsobates was observed, which occurs simultaneously with the Au oxidation features. Scan rate dependent cyclic voltammetry experiments reveal that the peak current in the Te UPD peak is not a linear function of the scan rate, nu, but of a 2/3 power of the scan rate, nu(2/3). It is in good consistent with a two-dimension nucleation and growth mechanism. (c) 2006 Elsevier Ltd. All rights reserved.