MOF-derived Mo-CoP@NiFe LDH hierarchical nanosheets for high-performance hybrid supercapacitors

Abstract

The well-designed hierarchical nanosheets composed of different components can enhance specific capacitances and cycling stabilities of electrode materials. Herein, [email protected] layered double hydroxide (LDH) hierarchical nanosheets were prepared by growing NiFe LDH nanosheets on MOF-derived ultrathin Mo-CoP nanosheets fabricated by etching Co-MOF with Mo ions. The hierarchical nanosheet structure can facilitate the transport of electrons/ions and provide numerous electroactive sites. Furthermore, the synergistic effects between the active materials provided more oxidation states for redox reactions. Owing to the hierarchical nanosheets and the synergistic effects between Mo-CoP and NiFe LDH, the [email protected] LDH electrode exhibited a large specific capacity of 1655 C g−1 (2796 F g−1) and good long-term stability with 79.6 % capacity retention after 8000 cycles. Additionally, the hybrid supercapacitor (HSC) delivered an energy density of up to 48.6 Wh kg−1 at 800 W kg−1 and outstanding cycling stability (90.6 % retention of the initial capacitance over 20,000 cycles).