The Synthesis Of Organic Dye Photosensitizer And Application In Photoinduced H₂ Production System

In recent 100 years, the exploitation and consumption of fossil fuels have brought serious environmental problems, such as the greenhouse effect, haze, air pollution and so on. Making clean energy such as hydrogen from solar energy is an ideal way to solve the environment pollution and energy crisis. Some algae has hydrogenase, which can produce hydrogen through photosynthesis. Inspired by this, developing an efficient artificial photosynthesis system to drive water to hydrogen has abroad high attention.Developing photosensitizer of high activity and stability is the key to photocatalytic hydrogen production system. In this thesis, we build a homogeneous photocatalytic hydrogen production system based on cobaloximes complexes as catalysts, triethanolamine(TEOA) as electron donor and two kinds of synthesized organic dyes as photosensitizer, the system does not contain precious metals.Firstly, we use 3-bromoaniline as raw material to synthesize three kinds of xanthene organic dyes through four steps. The three xanthene organic dyes are the pyronin derivative where the O on the framework was replaced by Si, Ge and Sn. The three xanthene organic dyes are identified by MS and NMR. Then construct a photocatalytic hydrogen production system based on cobaloxime complexes Co1 as catalysts, TEOA as electron donor, and the synthesized organic dyes as photosensitizer. We optimized the conditions of photocatalytic, and the optimal condition are as follows :MeCN/H2O(v/v=1:1) as solvent, TEOA(6%) as electron donor, pH=7. Under the optimal condition, the lifetime of the photocatalytic system is about 18 hours and the TON of H2 are 203, 228 and 258 respectively.Secondly, we use(4-Bromo-phenyl)-dimethyl-amine as raw material to synthesize seven novel nitrogen heterocyclic organic dye acridine derivatives and construct a homogeneous photocatalytic hydrogen producing system with cobaloxime complexes Co1 as catalysts, nitrogen heterocyclic acridine dye as photosensitizer and TEOA as electron donor. We also optimized the conditions of photocatalytic, and the optimal condition are as follows: MeCN/H2O(v/v=1:1) as solvent, TEOA(6%) as electron donor, pH=7. Under the optimal condition, seven nitrogen heterocyclic organic dye acridine derivatives are effective for H2 production. The system based on 12 and 15 as photosensitizer are more effective, the lifetime is about 50 hours and the TON of H2 are 1100 and 1280 respectively.Organic dye photosensitizers are flexible to prepare and low cost. They have potential applications in photocatalytic H2 generation system. Our study are useful for design of organic dye photosensitizers.