Transitional metal selenides have high conductivity,even metal quality,which makes them great for using as electrode materials for fabricating supercapacitors.Here,hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods on Ni ...Transitional metal selenides have high conductivity,even metal quality,which makes them great for using as electrode materials for fabricating supercapacitors.Here,hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods on Ni foam(NSR-Ni_(3)Se_(2)/Ni)was fabricated by a facile three-dimensional(3D)substrate-assisted confinement assembly method,and used as a freestanding electrode material for hybrid supercapacitors(HSCs).In this design,metallic Ni_(3)Se_(2)with hybrid 1D/2D architecture could effectively enhance the active specific surface area of electrode and improve space utilization,as well as significantly facilitate electrons transport,while Ni foam served as the Ni source of Ni_(3)Se_(2)and provided 3D multi-electron transport channels,thus boosting the specific capacity.The constructed hierarchical NSR-Ni_(3)Se_(2)electrode delivered a superior areal specific capacity of 1.068 mAh/cm^(2)(7.69 F/cm^(2))at 2 mA/cm^(2)and retained 68.2%of the initial capacity when the current density increases by 15 times.Furthermore,the as-assembled NSR-Ni_(3)Se_(2)device exhibited an ultrahigh energy density of 56.4 Wh/kg and high power density of 4640.3 W/kg,and a capacity retention of 92.6%even after 6000 cycles.展开更多
基金the financial support from the National Key R&D Program of China(Nos.2017YFB1104300 and 2016YFA0200200)National Natural Science Foundation of China(Nos.21575014,21905025,91963113)。
文摘Transitional metal selenides have high conductivity,even metal quality,which makes them great for using as electrode materials for fabricating supercapacitors.Here,hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods on Ni foam(NSR-Ni_(3)Se_(2)/Ni)was fabricated by a facile three-dimensional(3D)substrate-assisted confinement assembly method,and used as a freestanding electrode material for hybrid supercapacitors(HSCs).In this design,metallic Ni_(3)Se_(2)with hybrid 1D/2D architecture could effectively enhance the active specific surface area of electrode and improve space utilization,as well as significantly facilitate electrons transport,while Ni foam served as the Ni source of Ni_(3)Se_(2)and provided 3D multi-electron transport channels,thus boosting the specific capacity.The constructed hierarchical NSR-Ni_(3)Se_(2)electrode delivered a superior areal specific capacity of 1.068 mAh/cm^(2)(7.69 F/cm^(2))at 2 mA/cm^(2)and retained 68.2%of the initial capacity when the current density increases by 15 times.Furthermore,the as-assembled NSR-Ni_(3)Se_(2)device exhibited an ultrahigh energy density of 56.4 Wh/kg and high power density of 4640.3 W/kg,and a capacity retention of 92.6%even after 6000 cycles.
