Flexible Bifunctional Electrode for Alkaline Water Splitting with Long-Term Stability

Area of Science:

• Materials Science and Engineering
• Electrochemistry
• Renewable Energy Technologies

Background:

• Efficient and earth-abundant bifunctional electrocatalysts are crucial for advancing electrochemical water-splitting devices.
• Current research focuses on developing cost-effective and scalable electrode materials for clean energy generation.

Purpose of the Study:

• To develop a novel flexible and bifunctional electrode for stable and efficient overall water-splitting (OWS).
• To investigate the catalytic activity of hybridized carbon nanotube ribbons and NiO quantum dots in alkaline electrolytes.

Main Methods:

• Hybridization of macroscopically assembled carbon nanotube ribbons with atmospheric plasma-synthesized NiO quantum dots.
• Fabrication of bifunctional electrodes with varied NiO quantum dot loadings.
• Electrochemical testing in alkaline electrolytes using a two-electrode electrolyzer cell configuration.

Main Results:

• The developed electrode exhibited strong bifunctional activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media.
• Achieved a low cell potential of 1.81 V at 10 mA/cm² with minimal NiO quantum dot loading (83 μg/cm²).
• Demonstrated remarkable long-standing stability, retaining ~100% of initial current after 100 hours of OWS.

Conclusions:

• The synergistic coupling between NiO quantum dot catalysts and the carbon nanotube ribbon matrix enhances catalytic performance and stability.
• This study presents a cost-effective and scalable pathway for developing advanced electrodes for alkaline water-splitting and green hydrogen generation.