Enhanced photocatalytic hydrogen production in a UV-irradiated fluidized bed reactor

UV-irradiated fluidized bed reactor system and Pt-loaded TiO2 spheres were developed for photocatalytic water splitting. This novel approach was explored as a means to minimize the parasitic back reaction, mass transport and radiation distribution effects that limit the performance and scalability of immobilized-film and suspended slurry photocatalysts typically employed for photocatalytic hydrogen production. By fluidizing Pt-loaded TiO2 spheres in a 2.2 M Na2CO3 solution, steady hydrogen production rates up to 211 mu mol/h with an apparent quantum efficiency of 1.33% were achieved upon UV-irradiation. This demonstrates a marked 44% increase in the apparent quantum efficiency when compared to the performance of a traditional Pt-loaded TiO2 suspended slurry photocatalyst in the same reactor. It is hypothesized that this enhanced performance is primarily due to improved separation of the evolved H-2 and O-2 from the Pt-loaded photocatalyst particles, thus reducing the parasitic back reaction. (C) 2017 Elsevier Inc. All rights reserved.