Single-step grown boron doped nanocrystalline diamond-carbon nanograss hybrid as an efficient supercapacitor electrode

Abstract

Direct synthesis of a nano-structured carbon hybrid consisting of vertically aligned carbon nanograsses on top of boron-doped nanocrystalline diamond is demonstrated and the carbon hybrid is further applied as an electrode material for the fabrication of supercapacitors. The hybrid film combines the dual advantages of sp(2) (carbon nanograss) and sp(3) (nanocrystalline diamond) bonded carbon, possessing not only the excellent electrical characteristics of sp(2) carbon but also the exceptional electrochemical stability of sp(3) carbon. As a result, the specific capacitance of the as-prepared hybrid material reaches up to 0.4 F cm(-2), one of the highest reported in diamond-based supercapacitors. The entire electrochemical results exhibit enhanced electron transfer efficiency with remarkable stability of 95% of capacitance retention even after 10 000 cycles.