Tellurium underpotential deposited ad-atoms on Au electrodes: A new electrodeposition mechanism using an electrochemical quartz crystal nanobalance

Autor(es)

Santos, M. C. ^[1] ; Cabral, M. F. ^[2] ; Machado, S. A. S. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Abc, CCNH, LEMN, BR-09210170 Santo Andre, SP - Brazil

^[2] Univ Sao Paulo, Inst Quim Sao Carlos, Grp Mat Eletroquim & Metodos Eletroanalit, BR-13566590 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Electrochimica Acta; v. 58, p. 1-5, DEC 30 2011.
• Citações Web of Science: 9

Resumo

Interfacial phenomena involved in the underpotential deposition of tellurium layers were studied with an electrochemical quartz crystal nanobalance (EQCN) in perchloric acid solution (pH = 1). The in situ study of the oxidation kinetics showed that the oxidation of the Te layer deposited neighbor a Te(ads)/Au provides evidence of TeO(2ads) formation with the incorporation of oxygen to induce the formation of H(2)TeO(3). From the calculations of the first tellurium layer (82 ng cm(-2)), the mass expected for the second layer deposited in underpotential control was found. Moreover, the oxidation of Te(ads) followed a bi-functional mechanism involving the oxygen incorporated before the tellurium oxidation at high overpotentials. The combination of powerful interfacial methods (cyclic voltammetry and EQCN) gives a new perspective on tellurium electrodeposition and leads to a comprehensive understanding of the interfacial architecture. (C) 2011 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 10/16511-6 - Nanoestruturas para a geração de energia a partir de biocombustível
• Beneficiário: Mauro Coelho dos Santos
• Modalidade de apoio: Auxílio à Pesquisa - Regular