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.