Construction And Catalytic Study Of Electrospun Carbon-based Electrode For Vanadium Redox Flow Battery

In recent years,vanadium redox flow battery as a large energy storage technology has attracted wide attention because of no cross contamination,high efficiency and long cycle life.Electrode plays an important role in the overall performance of the battery.Electrospun carbon nanofibers has advantages of simple preparation,good controllability,and low cost,but the electrochemical performance still needs to be improved.Carbon nanofibers were optimized by in situ modification and chemical activation.Iridium chloride(H₂Ir Cl₆)was selected as the source of iridium,and metal Ir modified carbon nanofiber composites(CF/Ir)were prepared by hydrogen reduction at high temperature.The morphology,structure,physical and chemical properties shows that Ir was evenly distributed on the surface of carbon nanofibers and has good catalytic activity and wettability.The CF-Ir-2 electrode obtained with 0.030 g of H₂Ir Cl₆ shows the best electrocatalytic activity for VO²⁺/VO₂⁺couple.Compared with pristine cell,the energy efficiency of the cell using CF-Ir-2 is increased by 7.2%at 150 m A cm^-2.CNF/Cr₂O₃ composites were prepared with chromium nitrate and polyacrylonitrile as precursors.The electrochemical properties and catalytic mechanism of CNF/Cr₂O₃composites were studied.The CNF-Cr₂O₃-10 electrode with 10 wt%content Cr₂O₃ has the best electrochemical performance because of the synergistic effect between high catalysis of Cr₂O₃ and conductivity of carbon nanofiber.At 150 m A cm^-2,the discharge capacity of the cells assembled using CNF-Cr₂O₃-10 is improved by 77.2%.Carbon nanofibers were modified by ammonium ferric citrate(FAC).And modified carbon nanofibers with high graphitization,large specific surface area and porous structure were constructed.The effects of FAC content and reaction temperature on the electrode morphology and electrochemical performance were investigated.CNF-700-4(temperature is 700°C,FAC and carbon nanofibers in mass ratio of 4:1)possesses the best electrochemical performance and good charge and discharge performance.Figure 47;Table 13;Reference 80...