Synthesis of Hierarchical Cobalt Phosphate Nanoflakes and Their Enhanced Electrochemical Performances for Supercapacitor Applications

Abstract

Hierarchical structured cobalt phosphate (Co-3(PO4)(2)) nanoflakes were synthesized by simple co-precipitation method and employed as electrodes for supercapacitor. The purity and phase formation of the synthesized (Co-3(PO4)(2)) nanoflakes were ascertained by XRD and XPS measurements. The surface morphology and elemental composition of the Co-3(PO4)(2) nanoflakes were observed by using FE-SEM, TEM and EDS. The electrochemical behaviour of the present material as an anode material for supercapacitor was explored by cyclic voltammetric measurements and galvanostatic charge-discharge analysis. The specific capacitance for the as-synthesized and calcined (Co-3(PO4)(2)) nanoflakes electrodes was 132 and 210 Fg(-1) at a scan rate of 10 mV s(-1). The enhanced electrochemical behaviour of the calcined Co-3(PO4)(2) nanoflakes might be due to its well crystalline nature which offers more active sites for faradaic reactions, good conductivity and rapid diffusion of the electrolyte ions. The fabricated Co-3(PO4)(2) electrode displayed an excellent cyclic stability with 95% retention of initial specific capacitance after 800 cycles. An enhanced effect on the electrochemical properties of the Co-3(PO4)(2) nanoflakes has been proposed.