Performance Study Of MOF Derivatives-based Catalysts For Zinc-air Batteries

With the increasing concern on the environmental pollution and energy crisis,the development of renewable energy alongside new energy storage systems have become the consensus of all countries to achieve energy saving and emission reduction for coping with the energy crisis.Zinc-air batteries（ZABs）have attracted much attention among the new energy storage batteries because of their high specific energy density,low cost and high safety.However,the insufficient catalytic activity and stability of oxygen electrocatalysts severely hinder the development of ZABs.Hence,in this thesis,TiC@N-C and MnO@Cu-N-C oxygen electrode catalysts with different morphologies are prepared based on a morphology-tunable zeolite imidazolium ester backbone（ZIF8）material by inducing and coordination techniques,which greatly improve the electrochemical performance of ZABs.TiC@N-C catalyst achieves an ORR half-wave potential of 0.81 V and a good stability at a current density of 5 m A cm^-2for 280 h,indicating an excellent electrocatalytic activity and stability.The ZABs using TiC@N-C further delivers a peak power density of 176 m W cm^-2.MnO@Cu-N-C catalyst exhibits both activity for oxygen reduction reaction（ORR）and oxygen evolution reaction（OER）,where the ORR half-wave potential is0.81 V and the OER potential is 1.64 V at a current density of 10 m A cm^-2.The MnO@Cu-N-C-based ZAB demonstrates a peak power density as high as 196.8 m W cm^-2and a long-term stability at 10 m A cm^-2for 650 h,in which the voltage gap for the discharge and charge processes is only 0.7 V,manefesting that MnO@Cu-N-C oxygen electrode catalyst can be a very promising oxygen electrocatalyst for high-performance ZABs.