Supercapacitors display promising electrochemical performance with high power density and excellent cycle stability.However,their low energy density limits their advancement in a broader range of applications.To enhan...Supercapacitors display promising electrochemical performance with high power density and excellent cycle stability.However,their low energy density limits their advancement in a broader range of applications.To enhance their energy density,we proposed self-assembled spinel NiMn2S4nanoflakes grown on nickel foam which we successfully prepared by a facile hydrothermal method.The NiMn2S4electrode delivers a high capacitance of 2096.7 F g^(-1)at 1.0 A g^(-1),with an exceptional rate capability(~720.6 F g^(-1)at a very high current density of 100 A g^(-1))and good cycle stability(~85.1%retention of the initial capacitance after 7000 cycles with the Coulombic efficiency around 100%).The as-fabricated asymmetric supercapacitors based on NiMn2S4nanoflakes//active carbon demonstrate an energy density of 73.6 W h kg^(-1)at 800.5 W kg^(-1)and adequate cycling performance of~84.6%capacitance retention at 15 A g^(-1)after 10000 cycles.The results reveal that the nanostructured NiMn2S4is an excellent electrode material for high-performance energy storage applications.展开更多
基金partly supported by the Natural Science Foundation of Gansu,China(Grant Nos.22YF7GA009 and 20JR10RA611)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2021 sp54)。
文摘Supercapacitors display promising electrochemical performance with high power density and excellent cycle stability.However,their low energy density limits their advancement in a broader range of applications.To enhance their energy density,we proposed self-assembled spinel NiMn2S4nanoflakes grown on nickel foam which we successfully prepared by a facile hydrothermal method.The NiMn2S4electrode delivers a high capacitance of 2096.7 F g^(-1)at 1.0 A g^(-1),with an exceptional rate capability(~720.6 F g^(-1)at a very high current density of 100 A g^(-1))and good cycle stability(~85.1%retention of the initial capacitance after 7000 cycles with the Coulombic efficiency around 100%).The as-fabricated asymmetric supercapacitors based on NiMn2S4nanoflakes//active carbon demonstrate an energy density of 73.6 W h kg^(-1)at 800.5 W kg^(-1)and adequate cycling performance of~84.6%capacitance retention at 15 A g^(-1)after 10000 cycles.The results reveal that the nanostructured NiMn2S4is an excellent electrode material for high-performance energy storage applications.
