Construction And Catalysis Study Of Graphite Felt/Carbon Composite Materials For Vanadium Redox Flow Battery

Among all flow batteries,vanadium redox flow battery has developed rapidly due to its advantages.Graphite felt is the stock electrode of its,which has good conductivity and stability,but its poor electrochemical activity limits its development.By changing aniline polymerization environment,the morphology,elemental composition and microstructure of composite electrode was adjusted to further improve the performance of the battery.N-doped carbon nanonetwork-wrapped graphite felt electrode was prepared by electrodeposition and calcination.The carbon nanonetwork structure was obtained by adjusting the electrodeposition time and calcination temperature.The carbon nanofibers not only increase the electrode specific surface area,but also enhance the connectivity between graphite felt fibers.At 200 m A·cm^-2,the discharge capacity of modified cell is233 m A·h higher than that of blank cell.N,P co-doped carbon fiber/graphite felt composite electrode was prepared by introducing protonic acid,combined with electrodeposition and carbonization.The effects of protic acid concentration and species in deposition solution on morphology,foreign elements and properties of electrode were investigated.The introduced N and P elements make the electrode have more active sites.Electrochemical tests show that the performance of N,P co-doped electrodes is better than that of N-doped electrodes.At 200m A·cm^-2,the energy efficiency of modified cell is 7.2%higher than that of blank cell.A multi-dimensional carbon material modified graphite felt electrode（Co N/CNF/GF）with Co-N bonds was prepared by pyrolysis using ZIF-67 and polyaniline as intermediates.ZIF-67 and polyaniline-derived carbon materials provide reaction sites and conductive networks for electrode reactions.Co,N co-doping and multi-dimensional carbon structure can improve the hydrophilicity and conductivity of electrode and accelerate the adsorption,diffusion and electron transfer process.Co N/CNF/GF cell still maintains an energy efficiency of 55.7%at 300 m A·cm^-2.Figure 52;Table 3;Reference 93...