Formation of honeycomb-like Mn-doping nickel hydroxide/Ni3S2 nanohybrid for efficient supercapacitive storage

Abstract Herein, the honeycomb-like Mn-doping Ni(OH) 2 /Ni 3 S 2 nanohybrid is synthesized, via a one-pot hydrothermal reaction with multi-temperature adjustment. This distinct multi-temperature control achieves fast nanostructure transformation from thicker nanosheets to thinner nanosheets. The cross-linked honeycomb-like structure consists of abundant open space and internal ultrathin nanosheets. Meanwhile, the introduction of Ni 3 S 2 and Mn-doping into Ni(OH) 2 will generate synergistic effects in our nanohybrid. As expected, the nanohybrid electrode displays ultrahigh areal capacitance of 2518.8 mC cm −2 at a high current density of 1.2 mA cm −2 , and still possesses a high value of 1027.7 mC cm −2 even at 120 mA cm −2 . A hybrid supercapacitor was developed, which shows high energy density of 51.0 Wh kg −1 (at 425 W kg −1 ) and suitable cycling reversibility of 78.6% (after 5000 cycles). These results suggest this electrode material could serve as a promising candidate for energy-storage devices.