Probing the Catalytic Activity of Reduced Graphene Oxide Decorated with Au Nanoparticles Triggered by Visible Light

Author(s)

Wang, Jiale ^[1] ; Trindade, Fabiane J. ^[1] ; de Aquino, Caroline B. ^[2] ; Pieretti, Joana C. ^[2] ; Domingues, Sergio H. ^[2] ; Ando, Romulo A. ^[1] ; Camargo, Pedro H. C. ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, BR-05508000 Sao Paulo, SP - Brazil

^[2] Univ Prebiteriana Mackenzie, MackGraphe Graphene & Nanomat Res Ctr, BR-01302907 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: CHEMISTRY-A EUROPEAN JOURNAL; v. 21, n. 27, p. 9889-9894, JUN 26 2015.
• Web of Science Citations: 9

Abstract

Hybrid materials in which reduced graphene oxide (rGO) is decorated with Au nanoparticles (rGO-Au NPs) were obtained by the in situ reduction of GO and AuCl4(aq)- by ascorbic acid. On laser excitation, rGO could be oxidized as a result of the surface plasmon resonance (SPR) excitation in the Au NPs, which generates activated O-2 through the transfer of SPR-excited hot electrons to O-2 molecules adsorbed from air. The SPR-mediated catalytic oxidation of p-amino-thiophenol (PATP) to p,p'-dimercaptoazobenzene (DMAB) was then employed as a model reaction to probe the effect of rGO as a support for Au NPs on their SPR-mediated catalytic activities. The increased conversion of PATP to DMAB relative to individual Au NPs indicated that charge-transfer processes from rGO to Au took place and contributed to improved SPR-mediated activity. Since the transfer of electrons from Au to adsorbed O-2 molecules is the crucial step for PATP oxidation, in addition to the SPR-excited hot electrons of Au NPs, the transfer of electrons from rGO to Au contributed to increasing the electron density of Au above the Fermi level and thus the Au-to-O-2 charge-transfer process. (AU)

• FAPESP's process: 13/05709-8 - Palladium, Silver-Palladium, and Palladium-Platinum Nanomaterials: Maneuvering Shape, Composition, and Structure for Catalytic Applications
• Grantee: Jiale Wang
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 12/50259-8 - Graphene: photonics and opto-electronics: UPM-NUS collaboration
• Grantee: Antonio Helio de Castro Neto
• Support Opportunities: Research Projects - SPEC Program
• FAPESP's process: 13/19861-6 - Controlled metal nanomaterials for catalysis applications
• Grantee: Pedro Henrique Cury Camargo
• Support Opportunities: Regular Research Grants