Porosity-Engineered CNT-MoS₂ Hybrid Nanostructures for Bipolar Supercapacitor Applications

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Bipolar supercapacitors require electrode materials with high surface area, electrochemical stability, and conductivity.
• Tailoring pore size distribution and electrolyte interaction is key for optimal performance.

Purpose of the Study:

• To investigate the impact of electrolyte ionic properties on the electrochemical performance of porous CNT-MoS2 hybrid microstructures for bipolar supercapacitors.
• To evaluate the suitability of CNT-MoS2 hybrid electrodes for practical bipolar supercapacitor applications.

Main Methods:

• Electrochemical assessment of porous CNT-MoS2 hybrid electrodes using different electrolytes (1 M aqueous Na2SO4 and PVA-Na2SO4 gel).
• Evaluation of areal capacitance, Coulombic efficiency, and cycling stability over 7000 charge-discharge cycles.

Main Results:

• The CNT-MoS2 hybrid electrode demonstrated significantly higher areal capacitance in the negative potential window (122.3 mF cm-2 in Na2SO4) compared to the positive window.
• Areal capacitance in PVA-Na2SO4 gel electrolyte was 42.13 mF cm-2.
• High Coulombic efficiency (~102.5%) and excellent stability with capacitance retention (100% to ~180% over 7000 cycles) were observed.

Conclusions:

• The CNT-MoS2 hybrid microstructure shows promise for bipolar supercapacitor applications due to its superior performance in the negative potential window.
• The choice of electrolyte significantly influences the electrochemical properties and overall performance of the supercapacitor.
• The demonstrated stability and capacitance retention highlight the potential for long-lasting energy storage devices.