Performance of Fe-N/C Oxygen Reduction Electrocatalysts toward NO2-, NO, and NH2OH Electroreduction: From Fundamental Insights into the Active Center to a New Method for Environmental Nitrite Destruction

Autor(es)

Malko, Daniel ; Kucernak, Anthony ; Lopes, Thiago

• Tipo de documento: Artigo Científico
• Fonte: Journal of the American Chemical Society; v. 138, n. 49, p. 16056-16068, DEC 14 2016.
• Citações Web of Science: 25

Resumo

Although major progress has recently been achieved through ex situ methods, there is still a lack of understanding of the 7 behavior of the active center in non-precious metal Fe-N/C catalysts under operating conditions. Utilizing nitrite, nitric oxide, and hydroxylamine as molecular probes, we show that the active site for the oxygen reduction reaction (ORR) is different under acidic and alkaline conditions. An in-depth investigation of the ORR in acid reveals a behavior which is similar to that of iron macrocyclic complexes and suggests a contribution of the metal center in the catalytic cycle. We also show that this catalyst is highly active toward nitrite and nitric oxide electroreduction under various pH values, with ammonia as a significant byproduct. This study offers fundamental insight into the chemical behavior of the active site and demonstrates a possible use of these materials for nitrite and nitric oxide sensing applications or environmental nitrite destruction. (AU)

• Processo FAPESP: 14/50279-4 - Brasil Research Centre for Gas Innovation
• Beneficiário: Julio Romano Meneghini
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia
• Processo FAPESP: 14/09087-4 - Estudos sobre o uso do bioetanol em células a combustível do tipo PEMFC e SOFC
• Beneficiário: Marcelo Linardi
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/07848-3 - Desenvolvimento de Eletrocatalisadores para as Reações de Hidrogênio
• Beneficiário: Thiago Lopes
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado