Ultra-Fast Mass Transfer System by ∼100% Validated Micro-Basins for Large-Scale Photochemical Hydrogen Production

Area of Science:

• Materials Science
• Chemical Engineering
• Renewable Energy

Background:

• Photocatalytic hydrogen production is crucial for sustainable energy but limited by mass transfer inefficiencies in conventional systems.
• Disordered charge carrier migration and uncontrolled gas bubble evolution hinder overall hydrogen production efficiency.

Purpose of the Study:

• To develop a new mass transfer strategy for large-scale, efficient, and stable photocatalytic hydrogen production.
• To overcome intrinsic transport limitations and enable rapid hydrogen bubble detachment using a coalescence-induced jumping mechanism.

Main Methods:

• Designed a tunnel-junction photochemical diode integrated with a micro-basin array of metallic cocatalysts.
• Utilized a coalescence-induced jumping mechanism for ultra-fast hydrogen bubble detachment.
• Demonstrated an outdoor solar-driven photocatalytic reactor (25 cm × 25 cm) for large-scale validation.

Main Results:

• Achieved nearly 100% activation of surface catalytic sites, promoting directional charge carrier transport and rapid gas bubble evolution.
• Obtained a high hydrogen production rate of 177.53 µmol h⁻¹ cm⁻² and an apparent quantum yield of 70.7% under 420 nm illumination.
• Successfully demonstrated a large-scale GaN-based photochemical hydrogen-production system.

Conclusions:

• The developed mass transfer strategy effectively overcomes transport limitations in photocatalytic hydrogen production.
• The novel design provides a promising structural strategy for future solar hydrogen-generation technologies.
• This work validates the performance of a full-scale photocatalyst system for sustainable hydrogen production.