Simple synthesis of macroporous carbon–graphene composites and their use as a support for Pt electrocatalysts

Abstract

Macroporous carbon–graphene (MC–GR) composites were synthesized by a casting method using silica nanoparticles-graphene oxide (SiO2-GO) as the template and sucrose as the carbon precursor. The MC–GR composites combine the porous structure of MC with the excellent electrical and mechanical properties of GR. When used as a support for Pt electrocatalysts, Pt nanoparticles with an average diameter of 3.1±0.7nm are distributed onto the MC–GR. The MC on the surface of GR is beneficial for decreasing the aggregation of GR sheets and improving the diffusion of molecules through the GR sheets. Nonenzymatic amperometric sensor of glucose based on the Pt/MC–GR composites is developed. The Pt/MC–GR responds very rapidly to the changes in the level of glucose, producing steady-state signals within 3s. Due to the low potential, no obvious interference is observed with the addition of ascorbic acid, acetaminophen, dopamine, and uric acid. The Pt/MC–GR also exhibits significant catalytic activity for the oxidation of methanol. The maximum peak value of oxidation current density at Pt/MC–GR is 81.6mAmg−1, higher than that of Pt/GR (34.7mAmg−1) and Pt/MC (65.8mAmg−1).