Visible light promoted photocatalytic water oxidation: Effect of fluctuating light intensity upon reaction efficiency

Abstract

Visible light promoted photocatalytic water oxidations were conducted with a synthesized iron oxide nanoparticulate catalyst together with a [Ru(bpy)3]2+ light harvesting dye and electron acceptor. With highest intensity set at daylight equivalent levels, the effects of fluctuating illumination upon ongoing reactions were studied and gaseous O2 and proton production measured. A light oscillation cycle was identified that significantly increased reaction TOF and quantum yields, which is suggested to arise from improvements in synchronization of the cyclic reaction steps and minimization of light sensitizer self-decomposition.