A novel type of composite electrode based on nmltiwalled carbon nanotubes coated with sheet-like cobalt hydroxide particles was used in supercapacitors. Cobalt hydroxide cathodlcally deposited fiom Co（NO3）O2 solutio...A novel type of composite electrode based on nmltiwalled carbon nanotubes coated with sheet-like cobalt hydroxide particles was used in supercapacitors. Cobalt hydroxide cathodlcally deposited fiom Co（NO3）O2 solution with carbon nanotubes as matrix exhibited large pseudo-capacitance of 322 F/g in 1 mol/L KOH. To characterize the cobalt hydroxide nanocomposite electrode, a charge-discharge cycling test, cyclic voltammetry, and an impedance test were done. This cobalt hydroxide composite exhibiting excellent pseudo-capacitive behavior （i.c. high reversibility, high specific capacitance, low impedance）, was demonstrated to be a candidate for the application of electrochemical supercapacitors. A combined capacitor consisting of cobalt hydroxide composite as a cathode and activated carbon fiber as an anode was reported. The electrochemical pcrformance of the combined capacitor was characterized by cyclic voltammetry and a dc charge/discharge test. The combined capacitor showed ideal capacitor behavior with an extended operating voltage of 1.4 V. According to the extended operating voltage, the energy density of the combined capacitor at a current density of 100 mA/cm^2 was found to be 11 Wh/kg. The combined capacitor exhibited high-energy density and stable power characteristics,展开更多
Low volumetric energy density is a bottleneck for the application of lithium-sulfur (Li-S)battery.The low- density sulfur cooperated with the light-weight carbon sub- strate realizes electrochemical cycle stability,bu...Low volumetric energy density is a bottleneck for the application of lithium-sulfur (Li-S)battery.The low- density sulfur cooperated with the light-weight carbon sub- strate realizes electrochemical cycle stability,but leads to worse volumetric energy density.Here,nickel ferrite (NiFe2O4)nanofibers as novel substrate for sulfur not only anchor lithium polysulfides to enhance the cycle stability of sulfur cathode,but also contribute to the high volumetric capacity of the S/nickel ferrite composite.Specifically,the S/ nickel ferrite composite presents an initial volumetric capacity of 1,281.7mA h cm^-3-composite at 0.1C rate,1.9times higher than that of S/carbon nanotubes,due to the high tap density of the S/nickel ferrite composite.展开更多
文摘A novel type of composite electrode based on nmltiwalled carbon nanotubes coated with sheet-like cobalt hydroxide particles was used in supercapacitors. Cobalt hydroxide cathodlcally deposited fiom Co（NO3）O2 solution with carbon nanotubes as matrix exhibited large pseudo-capacitance of 322 F/g in 1 mol/L KOH. To characterize the cobalt hydroxide nanocomposite electrode, a charge-discharge cycling test, cyclic voltammetry, and an impedance test were done. This cobalt hydroxide composite exhibiting excellent pseudo-capacitive behavior （i.c. high reversibility, high specific capacitance, low impedance）, was demonstrated to be a candidate for the application of electrochemical supercapacitors. A combined capacitor consisting of cobalt hydroxide composite as a cathode and activated carbon fiber as an anode was reported. The electrochemical pcrformance of the combined capacitor was characterized by cyclic voltammetry and a dc charge/discharge test. The combined capacitor showed ideal capacitor behavior with an extended operating voltage of 1.4 V. According to the extended operating voltage, the energy density of the combined capacitor at a current density of 100 mA/cm^2 was found to be 11 Wh/kg. The combined capacitor exhibited high-energy density and stable power characteristics,
基金supported by the New Energy Project for Electric Vehicles in National Key Research and Development Program (2016YFB0100200)the National Natural Science Foundation of China (21573114 and 51502145)
文摘Low volumetric energy density is a bottleneck for the application of lithium-sulfur (Li-S)battery.The low- density sulfur cooperated with the light-weight carbon sub- strate realizes electrochemical cycle stability,but leads to worse volumetric energy density.Here,nickel ferrite (NiFe2O4)nanofibers as novel substrate for sulfur not only anchor lithium polysulfides to enhance the cycle stability of sulfur cathode,but also contribute to the high volumetric capacity of the S/nickel ferrite composite.Specifically,the S/ nickel ferrite composite presents an initial volumetric capacity of 1,281.7mA h cm^-3-composite at 0.1C rate,1.9times higher than that of S/carbon nanotubes,due to the high tap density of the S/nickel ferrite composite.
