Electrochemical generation of hydrogen peroxide using cerium oxide nanostructures supported on graphene: Synthesis, characterization, and application in wastewater treatment

Autor(es)

Lima, Thays S. ; Santos, Mauro C. ; Motheo, Artur J.

• Tipo de documento: Artigo Científico
• Fonte: Electrochimica Acta; v. 521, p. 8-pg., 2025-02-28.

Resumo

This study investigates the electrochemical generation of hydrogen peroxide (H2O2) using three distinct cerium oxide nanostructures-nanorods, nanospheres, and nanoparticles-supported on graphene. The nanorods and nanospheres were synthesized via the hydrothermal method, with controlled adjustments to centrifugation speed, calcination temperature, and duration to tailor their morphology. Cerium nanoparticles were prepared using a coprecipitation method. These nanostructures were employed to modify graphene and were evaluated for their performance in H2O2electrogeneration. Among them, cerium nanorods exhibited the highest H2O2pro- duction, achieving a 91 % efficiency. This superior performance can be attributed to the presence of oxidizing species (Ce3+), as identified through Raman spectroscopy, along with oxygen vacancies and enhanced surface hydrophilicity. Scanning electron microscopy (SEM) revealed that the nanorods were optimally distributed below the graphene sheets. The hydrothermal and coprecipitation synthesis methods proved effective for producing cerium oxide nanostructures with high catalytic activity. These findings highlight the potential of cerium oxide nanostructures as efficient catalysts for wastewater treatment via the electro-Fenton process. (AU)

• Processo FAPESP: 22/15252-4 - Eletrocatalisadores nanoestruturados para aplicação em células a combustível alcalinas-ácidas diretas de glicerol
• Beneficiário: Mauro Coelho dos Santos
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Regular
• Processo FAPESP: 22/04561-6 - Síntese e caracterização de um catalisador híbrido ternário (Nb2O5.La2O3.CeO2) suportado em grafeno para atuar como cátodo na remoção de desreguladores endócrinos por processos oxidativos avançados eletroquímicos (POAEs)"
• Beneficiário: Thays de Souza Lima
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 22/12895-1 - Processos avançados para a degradação de poluentes emergentes: materiais catalíticos, sensores eletroanalíticos e divulgação científica
• Beneficiário: Marcos Roberto de Vasconcelos Lanza
• Modalidade de apoio: Auxílio à Pesquisa - Temático