Hydrogen production by photocatalytic membranes fabricated by supersonic cluster beam deposition on glass fiber filters

• Photocatalytic membranes are fabricated by the innovative FlameBeam method.
• FlameBeam integrates supersonic cluster beam deposition with flame spray pyrolysis.
• Highly crystalline anatase TiO2, also with Pt nanoparticles, is produced in one step.
• Photocatalytic membranes perform well in H2 production from ethanol/water vapors.

Photoactive membranes coated with TiO2 and Pt/TiO2 nanostructured thin films were produced by one-step deposition of gas phase nanoparticles on glass fiber filters. Pt/TiO2 nanoparticles (0–1.5 wt.% Pt content) were produced by flame spray pyrolysis, starting from liquid solutions of the Ti and Pt precursors, and then expanded in a supersonic beam to be deposited on the filters. The nanostructured coatings were composed of crystalline nanoparticles (mainly anatase phase), without any need of post-deposition annealing. The so obtained photocatalytic membranes were tested in hydrogen production by photo-steam reforming of ethanol in an expressly set-up diffusive photoreactor. The reaction rate was found to increase with increasing the Pt content in the photoactive material, up to 1.5 wt.% Pt. The use of these membranes allowed a significant increase of the hydrogen production rate compared to that obtained with the same photoactive Pt/TiO2 films deposited on a quartz substrate.