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

Abstract

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.

GRAPHICAL ABSTRACT

IMPACT STATEMENT

P and Se have influence on the morphology and pore size of NiCo LDH, which make P, Se-NiCo LDH have more active sites, and thus promoting the reaction kinetics.

KEYWORDS:

• NiCo LDH
• flake structure
• P–Se co-doping

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was financially supported by the Scientific research project of Education Department of Jilin Province [Grant number JJKH20220999KJ] and the National Natural Science Foundation of China [Grant numbers  51871107, 52130101, 51631004].