The design of the electrode with high-area and mass capacitance is important for the practical application of supercapacitors. Here, we fabricated the porous NiCoP nanowalls supported by Ni foam(NiCo-P/NF) for superca...The design of the electrode with high-area and mass capacitance is important for the practical application of supercapacitors. Here, we fabricated the porous NiCoP nanowalls supported by Ni foam(NiCo-P/NF) for supercapacitors with win-win high-area and mass capacitance. The NiCoOH nanowall precursor was prepared by controlling the deposition rate of Ni^2+ and Co^2+ on NF through a sodium acetate-assisted(floride-free) process. After the phosphorization, the NiCo-P nanowalls formed with high loading about8.6 mg cm-2 on NF. The electrode combined several advantages favorable for energy storage: the plentiful pores beneficial for ion transport, the nanowalls for easy accommodation of electrolyte, good conductivity of NiCo-P for easy transport of electrons. As expected, the NiCo-P/NF exhibited a high specific mass capacitance(1,861 F g^-1 at 1 A g^-1,1,070 F g^-1 at 10 A g^-1 and high area capacitance(17.31 F cm-2 at 5 mA cm-2 and 10 F cm^-2 at 100 mA cm^-2.The asymmetric supercapacitor(ASC) composed of NiCo-P/NF positive electrode coupled with commercial active carbon negative electrode exhibited a high energy density of44.9 W h kg^-1 at a power density of 750 W kg^-1. The ASC can easily drive fans, electronic watch and LED lamps, implying their potential for the practical application.展开更多
基金support from the National Natural Science Foundation of China(21571054,21631004,21805073 and 21771059)the Natural Science Foundation of Heilongjiang Province(QC2018013)the Basic Research Fund of Heilongjiang University in Heilongjiang Province(RCYJTD201801)
文摘The design of the electrode with high-area and mass capacitance is important for the practical application of supercapacitors. Here, we fabricated the porous NiCoP nanowalls supported by Ni foam(NiCo-P/NF) for supercapacitors with win-win high-area and mass capacitance. The NiCoOH nanowall precursor was prepared by controlling the deposition rate of Ni^2+ and Co^2+ on NF through a sodium acetate-assisted(floride-free) process. After the phosphorization, the NiCo-P nanowalls formed with high loading about8.6 mg cm-2 on NF. The electrode combined several advantages favorable for energy storage: the plentiful pores beneficial for ion transport, the nanowalls for easy accommodation of electrolyte, good conductivity of NiCo-P for easy transport of electrons. As expected, the NiCo-P/NF exhibited a high specific mass capacitance(1,861 F g^-1 at 1 A g^-1,1,070 F g^-1 at 10 A g^-1 and high area capacitance(17.31 F cm-2 at 5 mA cm-2 and 10 F cm^-2 at 100 mA cm^-2.The asymmetric supercapacitor(ASC) composed of NiCo-P/NF positive electrode coupled with commercial active carbon negative electrode exhibited a high energy density of44.9 W h kg^-1 at a power density of 750 W kg^-1. The ASC can easily drive fans, electronic watch and LED lamps, implying their potential for the practical application.
