Enhanced hydrogen production by photoreforming of renewable oxygenates through nanostructured Fe2O3 polymorphs

Sunlight-driven hydrogen production via photoreforming of aqueous solutions containing renewable compounds is an attractive option for sustainable energy generation with reduced carbon footprint. Nevertheless, the absence of photocatalysts combining high efficiency and stability upon solar light activation has up to date strongly hindered the development of this technology. Herein, two scarcely investigated iron(III) oxide polymorphs, ?- and ?-Fe2O3, possessing a remarkable activity in sunlight-activated H2 generation from aqueous solutions of renewable oxygenates (i.e., ethanol, glycerol, glucose) are reported. For ?-Fe 2O3 and ?-Fe2O3, H2 production rates up to 225 and 125 mmol h-1 m-2 are obtained, with significantly superior performances with respect to the commonly investigated ?-Fe2O3. Sunlight-activated photoreforming of renewable oxygenates promoted by Fe2O3 nanosystems is a very attractive process for hydrogen production. In this context, scarcely investigated ?- and ?-Fe2O3 polymorphs, fabricated by chemical vapor deposition, show very promising performances for photocatalytic solar hydrogen generation. The present approach holds a remarkable potential even for the synthesis of added-value by-products, paving the way to manifold technological applications.