Sonoelectrochemical intercalation and exfoliation for the preparation of defective graphene sheets and their application as nonenzymatic H2O2 sensors and oxygen reduction catalysts
Abstract
A sonoelectrochemical synthetic method is reported for rapidly preparing and dispersing reduced graphene nanosheets (RGNSECM) stabilized in an aqueous electrolyte. The X-ray photoelectron and Raman results demonstrate that the defects on RGNSECM are predominantly physical and not similar to the chemical defects on reduced graphene nanosheets (RGNCM) synthesized via chemical reduction of graphene oxide nanosheets based on the Hummer's method. The in-plane crystallite size (La) of RGNSECM is 26.8 nm, larger than the 18.2 nm of RGNCM. The RGNs prepared using the sonoelectrochemical method (RGNSECM) were successfully applied as nonenzymatic H2O2 sensors and alkaline oxygen reduction reaction (ORR) catalysts. Using electrochemical analysis, a fair comparison of the performances of RGNSECM and RGNCM as H2O2 sensors and ORR catalysts has been performed.