Electrochemically Activated CNT Sheet as a Cathode for Zn-CO₂ Batteries.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Growing demand for electrochemical storage devices necessitates high-performance batteries.
• Zinc-Carbon Dioxide (Zn-CO2) batteries present a viable pathway for simultaneous CO2 reduction and energy storage.

Purpose of the Study:

• To fabricate and optimize a Zn-CO2 battery utilizing a carbon nanotube (CNT) sheet cathode.
• To enhance the performance of CNT cathodes through electrochemical activation and copper catalyst deposition for improved CO2 reduction.

Main Methods:

• Fabrication of a Zn-CO2 battery with a CNT sheet cathode and Zn anode.
• Electrochemical activation of the CNT electrode to increase surface area by approximately 4.5 times.
• Electrodeposition of copper (Cu) catalyst onto the activated CNT cathode with varying loadings to optimize CO2 reduction.

Main Results:

• The developed Zn-CO2 battery achieved an output voltage of 1.6 V at a current density of 0.063 mA/cm2.
• Electrochemical activation significantly increased the cathode's surface area, enabling higher catalyst loading and more active sites.
• Optimized Cu loading on the activated CNT cathode led to enhanced CO2 reduction efficiency.

Conclusions:

• The electrochemical activation process is crucial for enhancing CNT cathode performance in Zn-CO2 batteries.
• Activated CNT sheets with Cu catalyst demonstrate significant potential as cathode materials for advanced Zn-CO2 batteries.
• The study highlights a promising approach for developing efficient and high-voltage electrochemical energy storage systems.