The Research On The Supercapacitor Performance Of A Zinc-containing POMCPs@Ti₃C₂T_x Material

Supercapacitors are a new generation of green energy storage equipment due to their advantages of high power density and long cycle life.The development of electrode materials is of key significance to the research of a new generation of high-performance supercapacitors,and has become a research hotspot in the field of supercapacitors in recent years.Polyoxometalate-based coordination polymers（POMCPs）is a pseudo capacitance material with both negative potential window and high specific capacitance,which is expected to become a new type of electrode material for supercapacitors with excellent performance.In this paper,a kind of POMCPs was prepared by hydrothermal method based on classical Keggin silicotungstate salts.POMCPs electrode material,namely[Zn（itmb）₃H₂O][H₂Si W₁₂O₄₀]·5H₂O（Compound 1）.The specific capacitance of the glassy carbon electrode modified by compound 1 reaches 478.3 F g^-1when the current density is 5 A g^-1.In order to improve the conductivity of POMCPs electrode materials,this paper adopts ultrasonic treatment to compound POMCPs with MXene material Ti₃C₂T_x,and prepares five new 1@Ti₃C₂T_xelectrode materials by adjusting the material mass ratio.Namely 1@Ti₃C₂T_x-1,1@Ti₃C₂T_x-2,1@Ti₃C₂T_x-3,1@Ti₃C₂T_x-4 and1@Ti₃C₂T_x-5,the specific capacitance values of the modified glassy carbon electrode at the current density of 5 A g^-1reach 597.1,832.1,1480.1,1206.7 and 815.7 F g^-1.In addition,compound 1,after grinding and dispersion,acts as interlayer spacer and support of Ti₃C₂T_xmaterial,which effectively prevents interlayer self-stacking of MXene while improving the conductivity and cyclic stability of POMCPs.By using the synergistic effect between POMCPs material with high redox activity and MXene material with strong conductivity,its hybrid material shows excellent electric storage performance.The preparation and electrochemical properties of 1@Ti₃C₂T_xelectrode materials provide important experimental basis for the development and application of new high-performance supercapacitor electrode materials.