Starch-assisted electrochemical fabrication of high surface area cobalt hydroxide nanosheets for high performance supercapacitors

High surface area beta-Co(OH)(2)nanosheets is electro-synthesized through a simple deposition procedure, and their performance as supercapacitor electrode material is investigated. Cathodic electrodeposition of cobalt hydroxide was performed from 0.005 M CoCl2 at the direct current (DC) mode with applying current density of 10 mA cm(-2) and RT conditions. The obtained green deposit was characterized through XRD, IR, SEM, BET and TEM analyses. The result indicated that the electrodeposited sample has pure beta cobalt hydroxide phase with uniform hexagonal sheets. BET analysis showed that the prepared hydroxide has high surface area of 157.2 m(2) g(-1) with mesoscale pores. The charge storage ability of the prepared beta-Co(OH)(2) nanosheets were measured by cyclic voltammetry and continuous charge-discharge techniques, which revealed that the produced nanosheets are capable to deliver specific capacitance as high as 886.8 and 734.3 Fg(-1) at the current loads of 1 and 3 A g(-1), respectively, and capacity retentions of 93.9 and 83.7% after 3000 continuous cycling at these current loads. These electrochemical data proved the suitability of the prepared material for use in supercapacitor.