he Impact of Water Concentration on the Electro-Oxidation of Formic Acid on Platinu

Autor(es)

de Oliveira, M. G. ^[1] ; Melle, G. B. ^[1] ; Romano, R. L. ^[1] ; Varela, H. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Chem, BR-13560970 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Electrochemical Society; v. 169, n. 2 FEB 1 2022.
• Citações Web of Science: 0

Resumo

Water plays a pivotal role in several electrocatalytic reactions. In the electrooxidation of small organic molecules, water can for instance assist the oxidation of adsorbed species or inhibit the reaction through the oxidation of surface sites. This paper is the third in a series of studies aiming at evaluating the impact of water concentration on the electro-oxidation of small organic molecules on polycrystalline platinum. The study was performed in phosphoric acid electrolyte, and the water concentration was varied from 14 to 50 mol l(-1). Voltammetric profiles and potential oscillations were studied at distinct {[}H2O]/{[}H3PO4] ratios and constant concentration of formic acid. There is a diminution in the catalytic activity accompanying the decrease in the water concentration. The removal of carbon monoxide demands oxygenated species and can proceed in the absence of water for ethanol and methanol, but not for formic acid. Under oscillatory regime, the impact of water concentration, it is seen that higher water concentration implies higher oscillation frequencies, shorter and less stable time-series, and sharper transitions from low to high potential, where the adsorbed carbon monoxide is oxidized by adsorbed oxygenated species. Results are discussed in connection with the voltammetric study and also compared with other parent systems. (c) 2022 The Electrochemical Society ({''}ECS{''}). Published on behalf of ECS by IOP Publishing Limited. (AU)

• Processo FAPESP: 18/23942-5 - Acoplamento elétrico de osciladores eletrocatalíticos individuais
• Beneficiário: Rafael Luiz Romano
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 20/15230-5 - Centro de Pesquisa e Inovação de Gases de Efeito Estufa - RCG2I
• Beneficiário: Julio Romano Meneghini
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia
• Processo FAPESP: 19/22183-6 - Electrocatálise VI: aspectos fundamentais e aplicados em problemas emergentes e clássicos em conversão eletroquímica de energia
• Beneficiário: Edson Antonio Ticianelli
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 20/03519-0 - Obtenção de parâmetros cinéticos na oxidação eletrocatalítica de moléculas orgânicas pequenas
• Beneficiário: Murilo Gomes de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 21/09489-9 - Estudo microcinético da eletro-oxidação de moléculas candidatas a biocombustíveis para produção de hidrogênio e eletricidade
• Beneficiário: Murilo Gomes de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto