Diamond electrodes applied to the voltammetric generation of nitro-anion radicals from methyl parathion in aqueous media

Autor(es)

Lima, T. S. ^[1] ; Almeida, M. O. ^[2] ; La-Scalea, M. A. ^[1] ; Honorio, K. M. ^{[2, 3]} ; Santos, M. C. ^[4] ; Codognoto, L. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo UNIFESP, Inst Ciencias Ambientais Quim & Farmaceut, Dept Quim, Diadema, SP - Brazil

^[2] Univ Fed ABC UFABC, Ctr Ciencias Nat & Humanas CCNH, Santo Andre, SP - Brazil

^[3] Univ Sao Paulo, Escola Artes Ciencias & Humanidades, Sao Paulo, SP - Brazil

^[4] Univ Fed ABC UFABC, Lab Eletroquim & Mat Nanoestruturados LEMN, Ctr Ciencias Nat & Humans CCNH, Rua Santa Adelia 166, BR-09210170 Santo Andre, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: DIAMOND AND RELATED MATERIALS; v. 110, DEC 2020.
• Citações Web of Science: 0

Resumo

Electrochemical performance of methyl parathion (MP) at a boron-doped diamond (BDD) electrode was investigated in aqueous media by cyclic voltammetry (CV) and square wave voltammetry (SWV). Methyl parathion (MP) shows electroactivity on BDD electrodes, three peaks being registered corresponding to one oxidation (0.16 V) and two reduction peaks, at -0.53 V and 0.01 V. MP reduction is certainly pH-dependent. However, at pH > 9.0 the electrochemical reduction of MP involves a reversible reaction of one electron forming the nitro-anion radical (NAR). The nitro-anion radical undergoes disproportionation and its kinetic stability was evaluated by using a peak current ratio corresponding to the reversible pair R - NO2/R NO2 center dot-, and the second-order constant (k(2)) was determined. Moreover, thermodynamic parameters regarding the MP reduction mechanism and nitro anion radical generation were investigated by computational methods. (AU)

• Processo FAPESP: 17/10118-0 - Estudo e aplicação da tecnologia eletroquímica para a análise e a degradação de interferentes endócrinos: materiais, sensores, processos e divulgação científica
• Beneficiário: Marcos Roberto de Vasconcelos Lanza
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 17/21846-6 - Nanoestruturas para a remediação ambiental e produção de energia a partir de fontes renováveis
• Beneficiário: Mauro Coelho dos Santos
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Regular