Dandelion-like nickel/cobalt metal-organic framework based electrode materials for high performance supercapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) are emerging as advanced electrode materials for supercapacitors.
• Optimizing MOF composition and structure is crucial for enhancing electrochemical performance.

Purpose of the Study:

• To fabricate and characterize Ni-MOF and Ni/Co-MOF using a hydrothermal method.
• To investigate the effect of Ni/Co molar ratio on MOF morphology and supercapacitor performance.

Main Methods:

• Facile hydrothermal synthesis of Ni-MOF and Ni/Co-MOF with varied Ni/Co ratios.
• Electrochemical characterization using three-electrode and asymmetric supercapacitor systems.
• Morphological analysis of the synthesized MOF structures.

Main Results:

• Ni/Co-MOF with a dandelion-like hollow structure achieved a specific capacitance of 758 F/g at 1 A/g.
• Ni/Co-MOF exhibited enhanced rate capability (89% retention at 10 A/g) and cycling stability (75% retention after 5000 cycles).
• An asymmetric supercapacitor using Ni/Co-MOF delivered a high specific energy density of 20.9 Wh/kg at 800 W/kg.

Conclusions:

• The mixed-metal strategy effectively optimizes MOF morphology and electrochemical properties.
• Ni/Co-MOF presents a promising candidate for high-performance supercapacitor electrodes.
• Hydrothermal synthesis provides a facile route to advanced MOF materials for energy storage.