A Hydrogen Farm Strategy for Scalable Solar Hydrogen Production with Particulate Photocatalysts.

Scalable solar hydrogen production via water splitting using particulate photocatalysts holds great promise for renewable energy utilization. However, the photocatalytic overall water splitting still remains challenging due to the slow water oxidation kinetics, severe reverse reaction and H 2 /O 2 gas separation. Herein, mimicking nature photosynthesis, we demonstrated a practically feasible approach named "Hydrogen Farm Project" (HFP), which is composed of solar energy capturing and hydrogen production subsystems integrated by a shuttle ion loop, Fe 3+ /Fe 2+ . We found that well-defined BiVO 4 crystals with precisely tuned {110}/{010} facets are ideal photocatalysts to realize the HFP, giving up to 71% quantum efficiency for photocatalytic water oxidation and full forward reaction with nearly no reverse reaction. An overall solar-to-chemical efficiency over 1.9% and a solar-to-hydrogen efficiency exceeding 1.8% could be achieved. Furthermore, a scalable HFP panel for solar energy storage was demonstrated under sunlight outdoors. Our work offers a promising and practical strategy for large-scale solar energy conversion using particulate photocatalysts.