Autor(es)

Pinheiro, Nayara A. ; Assis, Marcelo ; Fernandes, Carlos H. M. ; de la Rosa, Yeison N. ; Silva, Anelisse B. ; Buzzo, Fernando A. ; Ribeiro, Caue ; Lanza, Marcos R. V. ; Maia, Ary S. ; Longo, Elson

• Tipo de documento: Artigo Científico
• Fonte: Journal of Alloys and Compounds; v. 1040, p. 17-pg., 2025-09-12.

Resumo

The development of efficient and stable photocatalysts for environmental remediation remains a key challenge in the treatment of emerging pollutants. In this work, heterostructured photocatalysts based on KNb3O8 and Ag3PO4 were successfully synthesized via a simple co-precipitation route and comprehensively characterized to evaluate their structural, optical, and photocatalytic properties. Structural characterizations confirmed the formation of well-defined crystalline phases and suggested interfacial lattice strain, indicative of strong interaction between the components. Among the prepared materials, the 50Nb3P composite, containing 50 wt% Ag3PO4, exhibited outstanding photocatalytic activity under visible light, achieving rapid degradation of Rhodamine B and high removal efficiencies for sulfamethoxazole (SMX) and ciprofloxacin (CIP), two antibiotics of environmental concern. Electronic analysis revealed enhanced visible-light absorption and suppressed electron-hole recombination, attributed to the heterojunction-driven charge separation. Scavenger tests confirmed that photogenerated holes were the dominant oxidative species, while electrons transferred to KNb3O8 promoted the generation of reactive oxygen species such as center dot OOH and O-1(2). Mineralization was verified by TOC and HPLC analyses, which showed decreased formation of persistent organic intermediates and improved conversion to CO2 and H2O. Although the catalyst showed performance loss over successive cycles due to photocorrosion, thermal treatment between uses effectively restored its activity. These findings demonstrate that the KNb3O8/Ag3PO4 heterostructure not only reduces the required amount of silver-based material but also offers a robust, cost-effective platform for the visible-light-driven degradation of persistent organic contaminants. (AU)

• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 18/22210-0 - EMU concedido no processo 2017/10118-0: cromatógrafo líquido (HPLC)
• Beneficiário: Marcos Roberto de Vasconcelos Lanza
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 23/08525-7 - Desenvolvimento de curativos cutâneos 3D de colágeno marinho enriquecidos com nanoparticulas funcionais para a regeneração de feridas cutâneas
• Beneficiário: Marcelo de Assis
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 18/22211-7 - EMU concedido no processo 2017/10118-0: analisador de carbono orgânico total (TOC)
• Beneficiário: Marcos Roberto de Vasconcelos Lanza
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• 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
• Processo FAPESP: 23/06558-5 - Eletrodos de difusão gasosa modificados com NPs de Co e/ou Fe e biochar para eletrogeração de H2O2 in situ e degradação de drogas antidepressivas: aspectos mecanísticos e tecnológicos
• Beneficiário: Carlos Henrique Magalhães Fernandes
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado