Preparation And Properties Of Bipyridine Ru Dye-sensitizer

The dye-sensitized nanocrystalline solar cell( NPC) is superior other kinds of chemical solar cell. The properties of dye-sensitizer will affect the light -electricity conversion efficiency of the solar cell. The main characteristics of dye-sensitizer are followed as: 1) dye-sensitizer must have a broad and strong absorption in the range of visible light; 2) The dye-sensitizer must have ability of interfacial charge exchange between dye-sensitizer and semiconducting solids; 3) The dye-sensitizer must have some functional groups that can make dye-sensitizer attach firmly on TiO2 surface. In the recent years many scholars concentrate on studies of low molecule dye-sensitizers. Because liquid electrolyte is widely used, it is found that dye-sensitizers can not attach efficiently on TiO2 surface. Now Cis- Ru (H2- debpy) 2(NCS)2 is the best sensitizer in all sensitizers, but the preparing process is much complicated, therefore looking for a new dye-sensitizer become very important. Focusing on development of the essential materials and on the review of the current research in NPC, we use N-vinylcarbazole as the cavity transferring material and use 4-methyl-pyridine to synthesize macromolecule dye-sensitizer Ru[p(vk-vA)]L22+. Firstly 4-Methyl-2,2'-bipyridines is synthesized through Stille coupling reaction, and then reacted with allyl chloride to get 4-(3–alkene–1–butyl)–2 ,2 ' –bipridine.The experiment results indicate that the nucleophilic agent is much important in Stille coupling reaction. Secondly 4-(3-alkene-1-butyl)-2,2'-bipridine is copolymerized with N–vinylcarbazole, high molecular weight bipyridines polymer is got by prolong reaction time. The structure of copolymer is characterized by NMR , IR ,UV,GPC.Thirdly the copolymer reacts with RuⅡL2cl2.2H2O to synthesize the macromolecule dye-sensitizer Ru[p(vk-vA)]L22+ . The N-vinylcarbazole chain segments in the copolymer are a cavity-transferring material that can improve the transferring capability of electron. The macromolecule characteristic and the presence of –COOH groups can increase the efficiency of NPC. Finally it is available to prepare solar cell by the measure of UV and cyclic voltammogram. The photocurrent test proves that the dye-sensitizer has dye-sensitized function and can get higher light photovoltaic.