Porous Mo-C coverage on ZnO rods for enhanced supercapacitive performance

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Zinc oxide (ZnO) is a cost-effective electrode material but suffers from low electrical conductivity.
• Carbon materials are often combined with ZnO to enhance its conductivity for supercapacitor applications.
• Porous carbon coatings can improve electrolyte accessibility and ion transport.

Purpose of the Study:

• To synthesize and characterize ZnO rods coated with a porous carbon layer (ZnO@Mo-C) for supercapacitor electrodes.
• To investigate the effect of porous carbon modification on electrochemical performance.
• To construct and evaluate an asymmetric supercapacitor device using the novel electrode material.

Main Methods:

• Synthesis of ZnO rods.
• Carbon coating of ZnO rods using dopamine hydrochloride modified with MoO42- to create porosity.
• Electrochemical characterization of ZnO@Mo-C composite for supercapacitors.
• Fabrication and testing of an asymmetric supercapacitor device.

Main Results:

• The ZnO@Mo-C composite exhibited excellent specific capacitance (900 F g-1 at 1 A g-1) and high rate capability (650 F g-1 at 10 A g-1).
• The porous carbon layer significantly improved electrolyte accessibility and ion transport.
• The asymmetric supercapacitor achieved a wide voltage window (0-1.5 V) and high capacitance retention (97% over cycling).

Conclusions:

• The facile and eco-friendly synthesis of ZnO@Mo-C provides a promising electrode material for high-performance supercapacitors.
• Porous carbon coating is an effective strategy to enhance the electrochemical properties of ZnO-based electrodes.
• The developed method is scalable and applicable to other carbon-coated materials for energy storage.