Boosting the performance of nickel–cobalt LDH cathode with phosphorus and selenium co-doping for hybrid supercapacitor

Through composition design and structural regulation, low electronegativity selenium and phosphorus were doped into NiCo LDH nanosheets to prepare phosphorus and selenium co-doped nickel–cobalt layered double hydroxide electrodes (P, Se-NiCo LDH), which can enhance the availability of active sites, significantly improve the conductivity and promote the reaction kinetics. Prepared it as a positive cathode of supercapacitor ultrahigh energy density (61.23 Wh kg−1) and power density (16496.5 W kg−1) can be obtained. Rate performance of the hybrid supercapacitor can be maintained 50.9% at 20 A g−1. Both excellent rate performance and energy density may promote the wider application of supercapacitors.