Synthesis of a graphene-carbon nanotube composite and its electrochemical sensing of hydrogen peroxide

Abstract Graphene, whose structure consists of a single layer of sp 2 -hybridized carbon atoms, provides an excellent platform for designing composite nanomaterials. In this study, we have demonstrated a facile process to synthesize graphene–multiwalled carbon nanotube (MWCNT) composite. The graphene–MWCNT composite material is endowed with a large electrochemical surface area and fast electron transfer properties in Fe(CN) 6 3−/4− redox species. A graphene–MWCNT composite modified electrode exhibits good performance in terms of the electrocatalytic reduction of H 2 O 2 ; a sensor constructed from such an electrode shows a good linear dependence on H 2 O 2 concentration in the range of 2 × 10 −5 to 2.1 × 10 −3  mol L −1 . The detection limit is estimated to be 9.4 × 10 −6  mol L −1 . This study provides a new kind of composite modified electrode for electrochemical sensors.