Facilely synthesized porous ZnCo2O4 rodlike nanostructure for high-rate supercapacitors

In the paper, a simple initial oxalate co-precipitation and subsequent high temperature calcination route has been employed to prepare porous ZnCo2O4 rodlike nanostructure. The rodlike ZnCo2O4 composed of obvious porous nanostructure has a size of about 26.78 nm. When used as supercapacitor, the electrochemical performances of rodlike ZnCo2O4 were clearly studied by liner sweep cyclic voltammetry, galvanostatic charge-discharge and EIS experiments. In detail, it can deliver a specific capacitance of 604.52 F g(-1) at 1 A g(-1) and have a capacity retention of 95.62 % over 3000 cycles. Excellent rate capability, 81.47 % specific capacitance retention for a 10-time scan rate rise and 62.17 % specific capacitance retention for a 10-time current density increase, is achieved. These results are much better than ZnO and Co3O4. Maybe, the enhanced electrochemical performances can be attributed to the porous rodlike structure and the synergy of Zn and Co. The high specific capacitance and excellent cycling ability of ZnCo2O4 show promise for its application in supercapacitors.