▎ 摘 要
A graphene/electrochemically reduced graphene oxide/polyallylamine electrode was developed to enhance its electrocatalytical activity for the reduction of hydrogen peroxide. Graphene oxide was coated and immobilized on top of a pristine graphene electrode via pi-pi bonding. Polyallylamine was then immobilized onto the surface of graphene oxide via covalent bonding and electrostatic adsorption. The graphene oxide layer was electrochemically reduced by cyclic voltammetry cycles. Polyallylamine acted as thread to crosslink graphene oxide films. During the reduction of hydrogen peroxide, a 28%, 411% and 279% increase of reduction currents were observed from the graphene/reduced graphene oxide/polyallylamine electrode, in comparison with those electrodes modified with graphene, reduced graphene oxide or polyallylamine, respectively. The improved electron transfer performance is attributed to the combination of the high electroactivity of reduced graphene oxide and the high conductivity of pristine graphene underneath.