High performance supercapacitor behavior of hydrothermally synthesized CdTe nanorods

Abstract

CdTe nanorods (NRs) have been prepared by hydrothermal process using ascorbic acid as a reducing agent. X-ray diffraction pattern reveals the formation of CdTe with cubic structure. From transmission electron microscopy the morphology of CdTe is found to be NRs with the length and diameter of 176 and 43 nm respectively. Brunauer–Emmett–Telle and Barrett–Joyner–Halenda analyses show the surface area (12.16 m2/g), pore volume (0.13 cm3/g) and pore diameter (44 nm). A high specific capacitance (438 F/g) is obtained at the current density of 2 mA/cm2 by the galvanostatic charge–discharge method. The excellent cyclic stability (95%) and the Coloumbic efficiency (99.7%) have been achieved even after 5000 cycles. The symmetric supercapacitor device exhibits the specific capacitance of 103 F/g at current density of 2.5 mA/cm2 with an energy density of 20.54 Wh/kg. The high density and electrochemical stability of the prepared CdTe electrode is a promising material for electrochemical energy storage devices.