Epitaxial‐Like Hydrothermal Growth of Planar Hematite Films for Water Splitting by Waste Remediation

The development of advanced photoelectrode materials for water splitting is as important as recycling to solve environmental problems. In this Communication, we report a facile hydrothermal epitaxial growth of hematite films from ferrioxalate solution, where the pH, isoelectric point and crystal nature of the substrates play key roles in the film growth. In a photoelectrochemical cell, the hematite photoanodes showed high activity to oxidize water, oxalate or phenol molecules, resulting in hydrogen generation on the counter electrode. This work shines a new light in the direction of environmental waste recycling.