Catalysis Today, Vol.318, 144-149, 2018
CoFe2O4 nanoparticles decorated carbon nanotubes: Air-cathode bifunctional catalysts for rechargeable zinc-air batteries
Exploring highly efficient bifunctional oxygen electrocatalysts are urgently for realizing rechargeable zinc-air batteries. Although CoFe2O4 as bifunctional oxygen electrocatalyst has been involved in less previous studies, CoFe2O4@CNTs as the high performance air cathode has not been reported. In this paper, the influences of temperature, time and the weight ratio of CNT to CoFe2O4 on the morphology, crystallographic forms and electrochemical performances of the final products are thoroughly investigated. The conclusion that amorphous form is efficient for ORR and, the crystalline structure is beneficial for OER was proposed. Particularly, a novel class of CoFe2O4@CNTs with amorphous form and crystalline structure has been successfully synthesized and exhibited excellent activity and stability in three electrodes test. More importantly, the CoFe2O4@CNTs cathodes are made and applied to zinc-air battery, which is demonstrated to be superior performances to Pt/C and IrO2 catalysts. The high power density (333.7 mW cm(-2)), larger specific capacity (732 mAh g(-1)), and excellent rechargeability (1200 stable charge-discharge cycles) proves the feasibility of CoFe2O4@CNTs application in large power energy-storage and conversion electronics.
Keywords:CoFe2O4@CNTs composite;Bi-functional electrocatalyst;Amorphous and crystalline;Rechargeable zinc-air battery