Microfluidic Photocatalytic Water-Splitting Reactors

In this work, we present a novel microfluidic photocatalytic water-splitting reactor. Optofluidics offers advantages over conventional reactors in terms of improved photon transfer efficiency and mass transfer efficiency and are therefore the ideal platform for photocatalytic reactions. Our device is a planar optofluidic device which we used to study the kinetics of Platinum-Impregnated Titanium Oxide as the oxygen and hydrogen producing photocatalyst redox mediated by Iodide/Iodate species. We deposit our catalysts via a sol-gel method while the platinum co-catalyst is added by wet impregnation via reduction in Sodium Borohydride. The reactions are performed under a 100W Hg lamp and reaction rates are inferred by measuring the depletion of the two Iodine species via UV-vis absorption spectrophotometry. Our results indicate that reaction rates and efficiencies can be enhanced by using an optofluidic platform as opposed to the conventional slurry reactor used in previous experiments for this class of reaction. We believe that the micro-optofluidic platform of our device offers the benefit of measuring the kinetic properties of these class of reactions quickly and cheaply for the goals of further optimization.Copyright © 2012 by ASME