Binder-free metal-organic frameworks-derived CoP/Mo-doped NiCoP nanoplates for high-performance quasi-solid-state supercapacitors.

The design of hierarchical nanostructures with a controlled composition arrangement is a promising strategy to achieve high ion transport and enhanced charge storage for high-performance supercapacitor electrode development. Herein, we report a high-energy-density electrode based on CoP/Mo-NiCoP nanoplates array on carbon cloth templated by the metal-organic frameworks (MOFs). The unique hierarchical 3D structure provides an extremely large surface that enables excellent accessibility to the active surface sites, promoting electrochemical energy storage performance effectively. In addition, according to the density functional theory (DFT) calculation, Mo-doped in CoP/NiCoP nanoplates results in a desired electronic structure to enhance electronic transfer capability. As a result, the CoP/Mo-NiCoP electrode presents a high specific capacity of 892.6 C g−1 (248 mAh g−1) at the current density of 1 A g−1, as well as good rate capability (78.9% of capacity at 20 A g−1), and long-term cycling stability (82.6% retention after 10000 cycles at 4 A g−1). Furthermore, the assembled supercapacitor yielded a high energy density of 64.7 Wh kg−1 at 800 W kg−1 with an operating voltage of 1.6 V, outperforming most asymmetric supercapacitors. This work shows a promising hierarchical nanomaterial array for the development of high-performance flexible supercapacitors. [ABSTRACT FROM AUTHOR]