Simultaneous Sulfite Electrolysis and Hydrogen Production Using Ni Foam-Based Three-Dimensional Electrodes

Area of Science:

• Electrochemistry
• Materials Science
• Sustainable Energy

Background:

• Sulfite electrolysis offers a dual benefit: hydrogen production and sulfur dioxide byproduct utilization.
• Developing efficient and stable electrocatalysts is crucial for advancing sulfite electrolysis.

Purpose of the Study:

• To evaluate the performance and stability of nickel foam (NF)-based electrodes for sulfite electrolysis.
• To investigate the use of functionalized NF as electrodes for sulfite electro-oxidation and hydrogen evolution reactions.
• To assess the feasibility of an electrochemical flow cell system for large-scale hydrogen production.

Main Methods:

• Functionalization of NF substrates via palladium electrodeposition and chemical oxidation.
• Utilizing a robust electrochemical flow cell coupled with in situ and ex situ measurements.
• Monitoring sulfite conversion and hydrogen production efficiencies at a current density of 10 mA·cm⁻².

Main Results:

• Achieved satisfactory sulfite conversion and hydrogen production efficiencies exceeding 90%.
• Demonstrated the effectiveness of 3D NF electrodes due to large surface area and enhanced mass transfer.
• Observed specific electrode property changes due to electrochemical dissolution and sulfur crossover.

Conclusions:

• NF-based electrocatalysts are suitable for efficient sulfite electrolysis and hydrogen production in flow cells.
• The developed system shows potential for large-scale industrial applications.
• Electrode stabilization and management are key considerations for long-term operation.