Facile synthesis of hierarchical Ni3Se2 nanodendrite arrays for supercapacitors

Rational design has been widely used to develop high-performance metal selenides-based electrode materials for supercapacitors. In this study, we develop a facile one-step solvothermal approach to synthesize binder-free Ni3Se2 nanodendrite arrays grown on nickel foam as advanced positive electrodes for supercapacitors. Our Ni3Se2 nanodendrite arrays on nickel foam exhibit a specific capacitance of 1234 F g−1 (3.70 F cm−2) at a current density of 1 A g−1 and a great rate capability, which is benefited from the excellent electrical conductivity and unique hierarchical nano-dendritic structure. Furthermore, an asymmetric supercapacitor device was assembled using activated carbon as the negative electrode and the Ni3Se2 nanodendrite arrays on nickel foam as the positive electrode, obtaining a high energy density of 22.3 W h kg−1 at a power density of 160.4 W kg−1.