| Texto completo | |
| Autor(es): |
Trevelin, L. C.
;
Valim, R. B.
;
Lourenco, J. C.
;
De Siervo, A.
;
Rocha, R. S.
;
Lanza, M. R. V.
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ADVANCED POWDER TECHNOLOGY; v. 34, n. 9, p. 10-pg., 2023-06-07. |
| Resumo | |
Oxygen reduction reaction (ORR) is an important reaction which is widely applied in advanced oxidative processes (AOP) through the in-situ electrogeneration of hydrogen peroxide. Oxygen gas can either be reduced to hydrogen peroxide via two-electron pathway or be converted to water in a competitive way via four-electron pathway. In this study, we report the effective enhancement of H2O2 generation in K2SO4 0.1 mol/L (pH 2) through the application of Printex L6 carbon (PL6C) modified with zirco-nium/niobium (ZrNb) and zirconium/molybdenum (ZrMo) oxides compared to unmodified PL6C. The proposed catalysts were prepared by the polymeric precursors synthesis method (on carbon). The cata-lysts were analyzed by X-ray fluorescence (FRX), transmission electron microscopy (TEM), and X-ray pho-toelectron spectroscopy (XPS), and were electrochemically characterised by cyclic voltammetry (CV) and hydrodynamic linear sweep voltammetry (LSV). The electroactivity of ZrNb/PL6C and ZrMo/PL6C oxides was analyzed in the ratio of 50/50 w/w. The results obtained from the electrochemical characterisations of the electrodes showed that the application of 5% ZrNb/PL6C and 1% ZrMo/PL6C yielded H2O2 selectivity of 84.3 and 77%, respectively, compared to 84.3% recorded for the unmodified PL6C. Also, based on the application of a determined current density, 5% ZrNb/PL6C and 1% ZrMo/PL6C recorded a potential shift of 200 and 400 mV to less negative potentials, respectively, compared to the unmodified PL6C, which implies in less energy consumption. The results obtained from the morphological and surface character-isations of the materials pointed to a practically homogeneous distribution of ZrO2, Nb2O5, and MoO3 with particle size of ca. 5 nm on the PL6C surface compared to the unmodified PL6C which exhibited par-ticle size of ca. 30-50 nm.& COPY; 2023 Society of Powder Technology Japan Published by Elsevier B.V. All rights reserved. (AU) | |
| Processo FAPESP: | 14/50945-4 - INCT 2014: Instituto Nacional de Tecnologias Alternativas para Detecção, Avaliação Toxicológica e Remoção de Micropoluentes e Radioativos |
| Beneficiário: | Maria Valnice Boldrin |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 16/12597-0 - Produção de eletrodos de difusão gasosa modificados com óxidos bimetálicos de Nb, Mo, Pd ou Zr para a produção de H2O2 in situ |
| Beneficiário: | Leandro Cesar Trevelin |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| 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: | 13/02762-5 - Desenvolvimento de tecnologias de prevenção à poluição: degradação e monitoramento on-line de antibióticos em esgotos |
| Beneficiário: | Robson da Silva Rocha |
| Modalidade de apoio: | Auxílio à Pesquisa - Jovens Pesquisadores |
| Processo FAPESP: | 21/12053-8 - Uso de lodo de tratamento de esgoto na síntese de carbono ativo modificado com óxidos nano estruturados (Ce, Nb, Ta, e Pd ) e sua aplicação na geração eletroquímica de peróxido de hidrogênio |
| Beneficiário: | Julio César Lourenço |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |