Electrochemical Studies of Hydrogen Peroxide Oxidation on a Nanoporous Gold Surface: Fundamental and Analytical Applications

Autor(es)

Arjunan, Ananthi ^{[1, 2]} ; Sukeri, Anandhakumar ^[1] ; Saraiva, Douglas Philip Martinez ^[2] ; Miranda, Paulo Barbeitas ^[1] ; Bertotti, Mauro ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo, Inst Chem, Dept Fundamental Chem, Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Electrochemical Society; v. 167, n. 11 JAN 8 2020.
• Citações Web of Science: 0

Resumo

A nanoporous gold (NPG) surface with high electroactive surface area and roughness factor was prepared via anodization-electrochemical reduction method and was used as a new platform to study the electrochemical oxidation of hydrogen peroxide (H2O2). Field-emission scanning electron microscopy (FE-SEM) analysis, cyclic voltammetry, and amperometry techniques were employed for structural morphology and electrochemical studies. The H(2)O(2)oxidation peak potential was significantly shifted (similar to 0.23 V) towards a less positive direction with increased current response at the NPG surface compared to that of a bare gold electrode. The mechanism for the H(2)O(2)anodic oxidation at the NPG surface was proposed based on the calculated transfer coefficient (alpha= 0.32) and the total number of electrons involved (n = 2.0) in the electrochemical process. Besides, the diffusion coefficient (D) of H(2)O(2)in PBS solution was also calculated using the Randles-Sevcik equation (2.18 x 10(-5)cm(2)s(-1)). In addition, the analytical application of the NPG electrode was demonstrated by amperometric detection of H(2)O(2)at a relatively less positive potential (0.57 V). The current increased proportionally to H(2)O(2)concentration in the linear range of 0.01 to 1.8 mM and the detection limit was found to be 0.6 mu M (S/N = 3). (AU)

• Processo FAPESP: 18/08782-1 - Sensores químicos miniaturizados e integrados: novas plataformas de fabricação para aplicações biológicas, clínicas e ambientais
• Beneficiário: Mauro Bertotti
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 18/02819-0 - Interação de quitosanas e surfactantes com modelos de membrana celular investigada por espectroscopia vibracional não linear
• Beneficiário: Paulo Barbeitas Miranda
• Modalidade de apoio: Auxílio à Pesquisa - Regular