Nanostructured KxNa1-xNbO3 hollow spheres as potential materials for the photocatalytic treatment of polluted water

Autor(es)

Praxedes, Fabiano R. ^{[1, 2]} ; Nobre, Marcos A. L. ^{[1, 2]} ; Poon, Po S. ^[3] ; Matos, Juan ^[4] ; Lanfredi, Silvania ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ Unesp, Inst Biosci Humanities & Exact Sci, BR-15054000 Sao Jose Do Rio Preto, SP - Brazil

^[2] Sao Paulo State Univ Unesp, Sch Sci & Technol, BR-19060900 Presidente Prudente, SP - Brazil

^[3] Univ Concepcion, Unidad Desarrollo Tecnol UDT, Barrio Univ S-N, Concepcion - Chile

^[4] Univ Autonoma Chile, Inst Ciencias Quim Aplicadas, Fac Ingn, Santiago 8900000 - Chile

• Tipo de documento: Artigo Científico
• Fonte: APPLIED CATALYSIS B-ENVIRONMENTAL; v. 298, DEC 5 2021.
• Citações Web of Science: 0

Resumo

Potassium-sodium niobate-based hollows spheres were studied in the photocatalytic degradation of Basic Blue 41 dye in aqueous phase under UV irradiation. KxNa1-xNbO3 materials were prepared at 700 degrees C by the spray pyrolysis method. Photocatalysts were characterized by XRD, SEM, TEM, N-2 adsorption/desorption isotherms and FTIR. Different kinetic models of adsorption, direct photolysis, and photocatalytic degradation of the azo-dye were performed as a function of the pH of solution. The increase in potassium content is responsible of the distortion and polarization of the niobate structure promoting a decrease in the energy band-gap down to 3.01 eV for K0.5Na0.5NbO3. The photocatalytic activity observed on k(0.5)Na(0.5)NbO(3) was up to 23 times higher than that on TiO2 in terms of the surface concentration of the azo-dye molecules adsorbed. A mechanism for the degradation of Basic Blue 41 azo-dye based on the reactive oxygen species detected by scavenger's tests and mass-spectroscopy analysis was proposed. (AU)

• Processo FAPESP: 20/00781-6 - Heteroestruturas baseadas em niobatos para a remediação de contaminantes orgânicos
• Beneficiário: Silvania Lanfredi
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 05/51242-8 - Emprego de indicadores de qualidade de água e outras ferramentas de gestão ambiental para avaliar o efeito das atividades antrópicas sobre os rios Preto, Turvo e Grande na região de São José do Rio Preto
• Beneficiário: Márcia Cristina Bisinoti
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 07/03510-9 - Caracterização estrutural de nanopós de óxidos semicondutores ferroelétricos
• Beneficiário: Silvania Lanfredi
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 14/11189-0 - Desempenho catalítico em função da nanoestruturação de novos catalisadores óxidos a partir do método de spray pirólise
• Beneficiário: Silvania Lanfredi
• Modalidade de apoio: Auxílio à Pesquisa - Regular