Branch-cell shape liked nickel-cobalt layer double hydroxides composite polypyrrole for high performance supercapacitor

Nickel-cobalt layered double hydroxides (NC-LDH) have high theoretical energy storage capacity, but are easily agglomerated, resulting in low conductivity and hindered charge transfer kinetics. Herein, the Branch-cell shape liked NC-LDH/PNT (polypyrrole nanotube) was easily prepared by the subsequent ion exchange reaction through the metal-organic framework ZIF-67 which was used as the precursor sacrificial template to first combine with the polypyrrole tube The specific capacity of the prepared NC-LDH/PNT at current density of 1 A g⁻¹ is 1280 F g⁻¹, and comparing to the specific capacity at 20 A g⁻¹ still keep 65%, When the power density of the asymmetric supercapacitor(ASC) is 787.5 W kg⁻¹, the energy density reaches 57.7 W h kg⁻¹, The cycling performance of the ASC was stable (the capacitance retention rate was 83.7% after 5000 cycles). Excellent electrochemical performance is attributed to the dispersed Branch-cell shape and high conductivity, which not only increases the reactive active sites of electrode materials, but also enhances the ion diffusion and charge transfer kinetics.