Effect of silver nanoparticles on TiO2-mediated photodegradation of Alizarin Red S

Autor(es)

de Souza, Michele L. ^[1] ; Corio, Paola ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, BR-05513970 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: APPLIED CATALYSIS B-ENVIRONMENTAL; v. 136, p. 325-333, JUN 5 2013.
• Citações Web of Science: 42

Resumo

Titanium oxide (TiO2) is widely employed in photocatalysis and in organic solar cells despite certain efficiency shortcomings regarding the high e(-)/h(+) pair recombination rate and wide E-gap. Wet chemistry immobilization of plasmonic Ag NPs onto commercial TiO2 (P25) through a bifunctional linker molecule (3-mercaptopropionic acid) was employed as a strategy to overcome such shortcomings. This paper proposes the main photodegradation excitation mechanisms according to the irradiation energy source. The photodegradation of the textile dye Alizarin Red S (ARS) catalyzed by bare P25 and a P25-Ag composite was studied applying UV/visible and visible radiation. Under UV/visible radiation, the P25-Ag composite showed a 40% improvement in the photodegradation rate constant in comparison to the bare P25, a phenomenon assigned to the charge separation due to the Schottky barrier. After 180 min under visible radiation the ARS degradation was 80%, i.e. low P25 photosensitization, while the P25-Ag composite showed a 7% increase in the percentage degradation of the unsaturated compounds, which was attributed to the plasmonic local field enhancement at the TiO2 surface. (C) 2013 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 98/14324-0 - Multidisciplinary Center for Development of Ceramic Materials
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 08/03636-5 - Nanocompósitos metálicos para aplicações em processos fotoquímicos intensificados: efeitos de plasmon em fotocatálise e fotoeletroquímica
• Beneficiário: Michele Lemos de Souza
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 08/57872-1 - Instituto Nacional de Ciências dos Materiais em Nanotecnologia
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Temático