Rice leaves microstructure-inspired high-efficiency electrodes for green hydrogen production

Area of Science:

• Electrochemical Engineering
• Materials Science
• Sustainable Energy

Background:

• Water electrolysis is crucial for green hydrogen production.
• Bubble accumulation on electrodes hinders efficiency in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER).

Purpose of the Study:

• To develop an advanced gas-conductive electrode for enhanced water electrolysis.
• To investigate the effect of anisotropic microstructures on bubble detachment and mass transfer.

Main Methods:

• Fabrication of a rice leaves-inspired anisotropic microstructured gas conduction electrode (Ni-conduction).
• Electrochemical characterization of HER and OER performance compared to a flat nickel electrode (Ni-smooth).
• Evaluation of an overall water-splitting device using the novel electrodes.

Main Results:

• The Ni-conduction electrode demonstrated rapid bubble detachment due to its microstructured grooves.
• Reduced overpotentials for HER/OER were achieved: 92/123 mV at 10 mA cm⁻² for Ni-conduction versus 183/176 mV for Ni-smooth.
• The Ni-conduction||Ni-conduction device required only 1.53 V for 10 mA cm⁻² overall water splitting.

Conclusions:

• Anisotropic microstructuring and wettability design are critical for improving gas evolution electrode performance.
• The rice leaves-inspired electrode design offers a promising strategy for efficient mass transfer and enhanced water splitting.
• This work presents a novel approach for developing superior electrodes for commercial green hydrogen generation.