An excellent strategy for synthesis of coral-like ZnFe2O4 particles for capacitive pseudocapacitors

Herein, coral-like ZnFe2O4 particles were prepared by a stepwise strategy, which contains a synthesis process and a subsequent etching process. Etching process can greatly improve the specific surface area of the ZnFe2O4. The specific surface area of the coral-like ZnFe2O4 particles is 200 times larger than that of the un-etched ZnFe2O4 particles. The ferric ion of ZnFe2O4 can be reduced gradually by hydrazine to form Fe2+, which will be coordinated with methyl mercaptoacetate to dissolve in DMF. Etched coral-like ZnFe2O4 particles have been tested as an electrode material for supercapacitor through electrochemical analysis. Etched coral-like ZnFe2O4 particles display a larger specific capacitance (∼471 F g−1) than the un-etched ZnFe2O4 particles (∼162 F g−1) at a scan rate of 2 mV s−1. An excellent stability of cycling performance with 80.6% specific capacitance retention after 3000 cycles can be achieved. The results suggest that the as-prepared coral-like ZnFe2O4 particles might be of potential application for supercapacitor electrode materials. The strategy paves an efficient way for synthesizing new ferrite particles with high specific surface area for the electrode material of supercapacitor.