Preparation And Electrochemical Performance Of Ti₃SiC₂/C Composite Electrode Materials

Ti3SiC2 is a ternary layered carbide of Mn+1 AXn phase,it with good processability,low Vickers hardness,good electrical and thermal conductivity has great application potential in the field of energy storage.In order to improve the electrochemical performance of Ti3SiC2,Ti3SiC2/Carbon composite nanofibers and Ti3SiC2/Carbon Cloth composite electrode materials were prepared by electrostatic spinning in this paper.The electrochemical properties of composite materials were improved obviously,especially the rare capability.In order to further improve the electrochemical performance,MnO2@NiCo2O4@Ti3SiC2/Carbon Cloth and NiCo2S4@Ti3SiC2/Carbon Cloth core-shell structure composites were prepared by a simple hydrothermal method.The core-shell structure can effectively improve the specific surface area of the composites and bring into play the synergistic effect of different electrode materials,thus improving the electrochemical performance.The main research works are as follows:(1)The Ti3SiC2/Carbon nanofibers were prepared by electrospinning and the effects of Ti3SiC2 addition on morphology and electrochemical performance were studied.The Ti3SiC2/Carbon nanofibers prepared with the addition of Ti3SiC2 at 1.2 g showed the best electrochemical performance.At the current density is 1 A/g,the specific capacitance is 133 F/g,and when the current density is increased to 10 A/g,the specific capacitance is 151.2 F/g,and the capacitance retention rate is 113.7%.After assembling ASC(Asymmetric supercapacitors)devices,the energy density is 7.02 Wh/kg at the power density is 140 W/kg.the capacitance remains 74.6%after 4000 cycles.Ti3SiC2/Carbon nanofibers have excellent electrochemical properties and are a promising electrode material.(2)The Ti3SiC2/Carbon Cloth composite electrode material was prepared by electrospinning and the effect of Ti3SiC2 addition on morphology and electrochemical performance was studied.When the addition amount of Ti3SiC2 is 0.4 g,the specific surface of Ti3SiC2/Carbon Cloth composite electrode material is 48.9 m2/g,and the specific capacitance is 176 F/g when the current density is 1 A/g.The Ti3SiC2/Carbon Cloth composite electrode material has excellent flexibility and can be used as an electrode material for flexible supercapacitors.(3)MnO2@NiCo2O4@Ti3SiC2/Carbon Cloth composite electrode material was prepared by a two-step hydrothermal method and the effect of hydrothermal time on the morphology and properties of NiCo2O4@Ti3SiC2/Carbon Cloth and MnO2@NiCo2O4@Ti3SiC2/Carbon Cloth was studied.MnO2@NiCo2O4@Ti3SiC2/Carbon Cloth exhibited excellent electrochemical properties when the time of the two-step hydrothermal method were 10 h and 2 h,respectively.The specific capacitance is 1938.2 F/g at the current density is 1 A/g,and the capacitance retention rate is 81.7%when the current density is 10 A/g,the capacitance remains 55.4%after 5000 cycles.After assembling ASC(Asymmetric supercapacitors)devices,the energy density is 58 Wh/kg at the power density is 800 W/kg,the capacitance remains 62%after 5000 cycles.MnO2@NiCo2O4@Ti3SiC2/Carbon Cloth composite electrode materials show excellent electrochemical performance and are a promising electrode material.(4)NiCo2S4@Ti3SiC2/Carbon Cloth composite electrode material was prepared by hydrothermal method and the effect of curing time on its morphology and electrochemical performance was studied.When the curing time is 6 h,the specific surface of the NiCo2S4@Ti3SiC2/Carbon Cloth composite electrode material is 129.4 m2/g,the area capacitance is 1.93 F/cm2 when the current density is 1 mA/cm2,the area capacitance is 0.89 F/cm2 when the current density is 10 mA/cm2,the capacitance retention rate of NiCo2S4@Ti3SiC2/Carbon Cloth is 47.3%.