Autor(es)

Mascarenhas, Bruno C. ^[1] ; Varanda, Laudemir C. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim Sao Carlos IQSC, Phys Chem Dept, Colloidal Mat Grp, BR-13566590 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY; v. 103, p. 124-135, NOV 25 2021.
• Citações Web of Science: 0

Resumo

Stable, efficient, and reusable catalysts for wastewater treatment, promoting the catalytic elimination of environmental pollutants remains a current challenge. This work shows a one-pot synthesize Ag nanoparticles (AgNPs) supported on reduced graphene oxide (rGO/Ag) as a nanocatalyst. Morphological control of AgNPs was achieved by adding NH4OH during the nucleation and growth processes leading to the spherical nanoparticles with average size of 9 +/- 3 nm). Temperature increase promotes decrease of the oxygenated functional groups on rGO sheets, with an I-D/I-G = 0.57 at 300 degrees C. Catalytic activity of rGO/Ag was investigated through the catalytic hydrogenation of methylene blue (MB) and rhodamine B (RhB) in the presence of NaBH4 as a reducing agent. The proposed mechanism is based on the transfer of 2e and 1H(+) between the nanocatalyst and the dye molecules. Dyes adsorption on the catalyst is a rate-determining step and was accelerated by the rGO support. X-ray photoelectron spectroscopy analysis before and after successive catalytic cycles indicated that the catalyst integrity was maintained, with a slight decrease in the silver amount from 4.53 to 3.78 at%. The decolorization reaction followed the pseudo-first-order kinetics model for both dyes, and our results showed an efficiency of around 30% higher than similar methods. (C) 2021 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 13/01284-2 - Nanopartículas teranósticas a base de óxido de ferro superparamagnético para terapia de câncer da pele via hipertermia magnética
• Beneficiário: Laudemir Carlos Varanda
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/18542-4 - Síntese e caracterização de compósitos de grafeno/nanopartículas (FePt, Fe3O4) pelo método poliol modificado
• Beneficiário: Rebecca Faggion Albers
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 12/02093-3 - Síntese de nanoestruturas core@shell de Co@Au (superparamagnéticas) e CdSe@ZnS (quantum dots) visando aplicações antineoplásicas
• Beneficiário: João Batista Souza Junior
• Modalidade de apoio: Bolsas no Brasil - Doutorado