Investigation Of Cobalt Tennary Gradient Catalyst And Electrochemical Performance For Lithium Oxygen Battery

Along with the increasing of environmental pollution and energy shortage,it is imperative to develop an energy system about clean,pollution-free and high energy efficiency.Therefore,the lithium oxygen battery with high theoretical energy has been widely concerned all over the world.At present,there are still many problems in the research of lithium oxygen battery,such as cathode material,electrolyte decomposition and anode protection,besides these,cathode material properties have a greater impact on lithium oxygen battery.This paper mainly studies the cathode catalyst material and applied to lithium oxygen battery.Firstly,the CoO catalyst was prepared by DC arc discharge plasma method,the catalyst has uniform particle size distribution,unobvious agglomeration,larger specific surface area and porosity.Compared with the traditional Mn-Pt catalyst,the Co-Pt binary catalyst has a lower charge transfer resistance.It can be obtained the maximum specific capacity of 2285.81 mAh g-1 and the highest energy density of 5582.80 mWh g-1 at the current density of 0.025 mA cm-2.Then,the CoO,La2O3 and Pt catalyst(Co-La-Pt catalyst)as ternary catalyst is applied to lithium oxygen battery,it showes that Co-La-Pt catalyst has showed low internal resistance by electrochemical analysis,Co-La-Pt ternary catalyst obtains maximum discharge specific capacity of 2484.35 mAh g-1 and maximum energy density of 6072.49 mWh g-1 at the current density of 0.01 mA cm-2.Finally,the gradient Co-La-Pt catalyst with three-layered structure is prepared and applied to lithium oxygen battery.The charge transfer resistance of this catalyst is small,the gradient Co-La-Pt catalyst with three-layered structure attains maximum specific capacitance of 3250.21 mAh g-1 and the maximum energy density of 8574.23 mWh g-1,charge and discharge cycle can steadily achieve 62 times at the current density of 0.025 mA cm-2.The electrochemical performance of this catalyst lithium oxygen battery is higher than that of the Co-Pt binary catalyst and Co-La-Pt ternary catalyst,and it shows excellent electrochemical performance.