Preparation Of Noble-metal-free Photocatalytic Materials And Their Photocatalytic Performances For Hydrogen Production By Splitting Water

Hydrogen is considered as a clean alternative energy carrier for the futurebecause of its high calorific value and since it only produces water upon combustion.It is believed that hydrogen will substitute fossil fuels as one of the next generationsof clean energy sources. Conversion of solar energy into molecular hydrogen hasattracted more and more attentions in recent years. Designing and preparing the cheapand efficient homogeneous catalysts for photocatalytic hydrogen production is themain goal of the scientists. In this article, four types of cobalt complexes based oninexpensive metals were designed and prepared, which used as photo-catalyst, somexanthene organic dyes as photosensitizer to construct efficient and noble-mental-freephotocatalytic hydrogen production system.First, the cobalt complexes C1、 C2were applied as photo-catalyst inphotocatalytic H2production system with Eosin Y dye (EY2-) as the photosensitizer,triethylamine (TEA) as electron donor. Under the optimal condition, the maximumamount of H2generated was249TON (vs. catalyst), the lifetime of the system isabout2hours of photocatalytic hydrogen production system. According to theresearch of system stability, the reason of deactivation for the system has been found. The dynamics studies help to find control step of the photocatalytic reaction underdifferent conditions, and further proved the mechanism of the system. Second, thecobalt complexes C3、C4were applied as photo-catalyst in photocatalytic H2production system. Under the optimal condition, the maximum amount of H2generated for C3、C4were1013TON and1134TON (vs. catalyst) after2hoursirradiation of visible light (λ>420nm). The studies of the structure of xantheneorganic dyes show the requirements of photosensitizer.