Controllable Hydrothermal Synthesis of Ni/Co MOF as Hybrid Advanced Electrode Materials for Supercapacitor

Abstract

Hierarchical structure plays an important part in the performance of supercapacitor materials. Herein, the Ni/Co hybrid MOFs with hierarchical sphere structure were synthesized controllably using the hydrothermal method. With the controlling molar ratio of Ni/Co and ligand, morphology evolution and optimized electrochemical performance of the hybrid MOFs were carefully studied. As a battery-type supercapacitor electrode material, the optimized Ni/Co hybrid MOF (Ni/Co-1:2) delivered a high specific capacity of 339.3 C·g−1 at the current density of 1 A·g−1 and good cycling performance of 70.3% retention after 2000 cycles in its direct use. The 2-electrode cell can deliver an energy density of 12.8 Wh·kg−1 at the power density of 372.5 W·kg−1. Our work not only develops a high-performance electrode material of supercapacitor, but also provides the foundation of systematic research for the electrochemical properties of multi-metal MOFs.