A high-performance asymmetric supercapacitor based on a directly grown nickel bicarbonate/nickel foam composite

作者：Long Lu; Fu Weidong; Yan Minglei; Yao Yadong^*; Wang Hongjing; Wang Meng; Liao Xiaoming; Yin Guangfu; Huang Zhongbing

来源：Electrochimica Acta, 2015, 180: 330-338.

DOI：10.1016/j.electacta.2015.08.129

• Three-dimensional structure
• Nickel bicarbonate/nickel foam
• Electrochemical properties
• Energy density
• Asymmetric supercapacitor

Three-dimensional (3D) network structure nickel bicarbonate/nickel foam (Ni(HCO3)(2)/NF) composite was synthesized by a simple one-pot hydrothermal process. The electrochemical properties of the as-prepared samples were investigated through the cyclic voltammetry and galvanostatic charge/discharge measurements. The results show that the specific capacitance of Ni(HCO3)(2)/NF reaches up to 2128.57 F g(-1) (corresponding to a specific area capacitance of 7.45 F cm(-2)) at a current density of 2.5 mA cm(-2), and the capacitance is still 876.19 F g(-1) (3.07 F cm(-2)) even at 50 mA cm(-2). Considering the excellent electrochemical performances of Ni(HCO3)(2)/NF electrode, an asymmetric supercapacitor based on Ni(HCO3)(2)/NF anode and FexCy/C cathode was assembled, which exhibited high energy density and power density. The maximum energy density of the asymmetric supercapacitor is up to 24.96 Wh kg(-1) at a power density of 87.75W kg(-1), besides, the power density can reach 1754.37 W kg(-1) at 6.92 Wh kg(-1). Moreover, two such 1 cm(2) devices connected in series could light five LED indicators (40 mW) after charging only 50 s, and power a LED indicator with the same power for half an hour after charging to 3.2 V. The results demonstrate that our asymmetric supercapacitor is a promising device for practical applications.

• 出版日期2015-10-20
• 单位四川大学