Galvanic Exchange on Reduced Graphene Oxide: Designing a Multifunctional Two-Dimensional Catalyst Assembly

• Published in: Journal of physical chemistry. C 2013-01, Vol.117 (1), p.571-577
• Main Authors: Krishnamurthy, Sachidananda, Kamat, Prashant V
• Format: Article
• Language: English
• Subjects: Catalytic methods; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in multilayers, nanoscale materials and structures; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; Materials science; Methods of nanofabrication; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Physics; Specific materials
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp309529b

The two-dimensional network of reduced graphene oxide (RGO) is decorated with silver and gold nanoparticles. The silver nanoparticles deposited on RGO by photocatalytic reduction are subjected to galvanic exchange with Au3+ ions to transform them into gold nanoparticles. This compositional change on the RGO surface demonstrates RGO’s versatile ability to anchor a wide array of nanoparticles and facilitate chemical transformations. Coupled with RGO’s unique ability to capture and transport electrons, galvanic exchange is used to contrive a two-dimensional nanocatalyst mat. Raman studies show that metal nanoparticles anchored on reduced graphene oxide facilitate enhancement of Raman bands. Using methyl viologen as a probe we elucidate the photocatalytic activity of the semiconductor–RGO–metal nanoassembly and highlight the mediation of RGO in charge transfer processes.