▎ 摘　　要

Herein, three-dimensional reduced graphene oxide/helical carbon nanotubes (RGO/HCNTs) nanocomposites were synthesized by a combined solution-based method and chemical vapor deposition. This synergistic structure of graphene and helical carbon nanotube exhibited large flexibility, rapid transport kinetics, and excellent electrochemical characteristic. The hemoglobin (Hb) was immobilized on the surface of the RGO/HCNTs nanocomposites for amperometric sensing of H2O2. The dependence of the electrochemical performance of Hb on the composition of RGO/HCNTs composites is systematically investigated by varying the weight ratio of reduced RGO/HCNTs. Compared with alone graphene or HCNTs electrodes modified with Hb, the catalytic current for H2O2 reduction at the Hb-modified RGO/HCNTs electrode increased due to the increase in the surface coverage of Hb and the excellent electrocatalytic activity of RGO/HCNTs. The constructed biosensor displayed a fast electron transfer of Hb and an excellent electrochemical activity for the detection of H2O2 with high selectivity and sensitivity.