Solubility-Dependent NiMoO₄ Nanoarchitectures: Direct Correlation between Rationally Designed Structure and...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Advanced pseudocapacitors require tailored metal oxide nanostructures for enhanced electrochemical performance.
• Controlling nanostructure morphology is key to optimizing energy storage capabilities.

Purpose of the Study:

• To synthesize one-dimensional (1-D) nickel molybdenum oxide (NiMoO4) nanostructures with controlled aspect ratios.
• To investigate the relationship between nanostructure morphology and electrochemical performance in pseudocapacitors.

Main Methods:

• Hydrothermal nucleation and crystal growth using a supersaturation-mediated driving force.
• Tuning the aspect ratio of 1-D NiMoO4 nanostructures.
• Fabrication and testing of electrodes and asymmetric supercapacitors.

Main Results:

• Successfully obtained 1-D NiMoO4 nanostructures with tunable aspect ratios (80-800 nm diameter).
• High-aspect-ratio (HAR) NiMoO4 electrodes showed a specific capacitance of 1335 F g-1 at 1 A g-1.
• Asymmetric supercapacitors using HAR-NiMoO4 achieved an energy density of 40.7 Wh kg-1 and a power density of 16 kW kg-1.

Conclusions:

• Controlled aspect ratio of 1-D NiMoO4 nanostructures enhances electrochemical kinetics and ion diffusion.
• HAR-NiMoO4 is a promising material for high-performance pseudocapacitors and supercapacitors.