Three-dimensional Porous Electrode Materials Based Cellular Nanofibers/Carbon Nanotube Films And Their Electrochemical Properties

Cellular nanofibers(CNF)and multi-walled carbon nanotubes(MWCNT)are widely used in energy storage,catalysis and adsorption because of their unique one-dimensional nanostructure and physical properties.In view of the good conductivity,excellent physical and chemical properties,good flexibility and film-forming properties of MWCNT,especially the excellent dispersion ability of CNF to MWCNT.In this paper,MWCNT and CNF are used as basic components,and a variety of three-dimensional porous electrode materials are prepared by template method.Their electrochemical properties and applications in supercapacitors are also studied.It mainly includes the following contents:1.Based on the characteristics of self aggregation of dispersed liquid in freeze-drying process,a three-dimensional porous MF/CNF/MWCNT(N-MCM)hybrid carbon material was successfully constructed by three-dimensional porous melamine foam(MF)as template and carbonized at high temperature.Then,high performance N-MCM-MnO2 and N-MCM-PPy electrode materials were prepared by redox and in-situ polymerization,respectively.In addition,the N-MCM-MnO2 and N-MCM-PPy electrode materials have good cycle life.The capacity retention rates after 5000 cycles at 10 mA/cm2 current density are 86.2%and 84.0%of the initial values,respectively.2.The "skin skeleton"structure of MWCNT/CNF-NF(MCN)hybrid material was prepared by using the three-dimensional network of nickel foam(NF)as the skeleton and the self aggregation of the MWCNT/CNF dispersion as the "skin".In this work,high specific capacities of PPy-MCN,MnO2-MCN and AC-MCN electrodes were prepared by using MCN as electrochemical active material platform.The area specific capacities of PPy-MCN,MnO2-MCN and AC-MCN electrodes were 2217.8 mF/cm2,1784.8 mF/cm2 and 868.8 mF/cm2 at 5 mA/cm2 current density,respectively.At the same time,two kinds of all-solid-state asymmetric supercapacitors(ASC),MnO2-MCN//PPy-MCN and MnO2-MCN//AC-MCN,were successfully assembled.Among them,the MnO2-MCN//PPy-MCN supercapacitor device has 11.9 F/cm3 volume capacitance and 5.1 mWh/cm3 energy density at 1.8 V voltage,and the MnO2-MCN//AC-MCN supercapacitor device has 9.8 F/cm3 volume capacitance and 4.2 mWh/cm3 volume energy at 1.8 V voltage window.The results show that N-MCM and MCN hybrid materials have good applicability and expansibility in the controllable construction of three-dimensional porous electrode materials.In addition,this type of three-dimensional porous electrode material has great application prospects in assembling asymmetric supercapacitors with high volume specific capacity,high energy density and good cyclic stability.