In Situ Electrochemical Synthesis of Rod-Like Ni-MOFs as Battery-Type Electrode for High Performance Hybrid Supercapacitor

Abstract

Metal-organic frameworks (MOFs) have become a potential energy storage material due to its high specific surface area, adjustable structure and functionality. Nevertheless, an efficient and controllable method to synthesize MOFs is still highly desired. Herein, we develop a simple and efficient electrochemical synthesis method, in which the Ni2+ ions are provided by nickel foam (NF), and rod-like arrays of Ni-MOFs are obtained in-situ on NF. The obtained products need no additional treatments and can be directly used as a binder-free electrode material. As a result of that, it can significantly improve the rapid transport of electrons and ions near the surface of the electrode. Particularly, the rod-like array Ni-MOFs grown on NF could self-assembled to be flower shaped structural characteristic, which demonstrated high capacity performance (area specific capacity of 5.11 C/cm2 at a current density of 2 mA/cm2) and excellent rate performance. In addition, the as-assembled Ni-MOF-1 h//AC hybrid supercapacitor (HSC) reveals a high energy density of 586.7 mWh/cm2 at a power density of 3679 mW/cm2.