Synthesis And Electron Transfer Of Viologen Polymer Side Groups To The Catalytic Performance Applications

The essence of photosynthesis is the light梚nduced charge separation and electron transfer. In recent years, research work in the field of solar energy usage has been focused on the simulation of photosynthesis , that is , hydrogen generation by the reduction of water . Electron relay梫iologen(N,N - 梔ialkyl--4,4 - 梔ipyridinium,V2t) of the four梕lement simulation system is well known to be subjected to one梕lectron reduction which produces the blue radical cation (Vs) that is easily reoxidized to V2~ Thus viologen has attracted much attention because it can be used as electron transfer catalyst in the reduction of organic substances. In our work ,we have synthesized polyviologens containing different spacers , characterized their structure , studied their chemical redox properties and their application as electron梩ransfer catalyst . The dissertation presents here the following main points: Chemical simulation of photosynthesis , Four梕lement system of the simulation system and the polymeric application of electron梤elay viologens (functional polymer) in the system are reviewed. Different types of homopolymer of viologen containing various -4- spacers and end梘roups, e. g. N?Y 梞ethacryloyloxypropyl桸 梟梐lkyl?, 4 ?梑ipyridinium dibromide and its analogs, were prepared and characterized by Infrared(IR) and 慔桸uclear Magnetic Resonance (H桸MR) Copolymer of N?y 梞ethacryloyloxypropyl桸 ?梟梐lkyl?,4 - 梑ipyridinium dibromide and acrylamide together with dimethylaerylamide were synthesized and characterized, the content of bromide was inspected by Elemental Analysis so that the content of viologen group could be acquired by calculation. Butylviologen and benzylviologen were synthesized and characterized as contrast to polyviologens. Research of the electron transfer catalytic abilities of polyviologen was proceeded as follows: Chemical reduction of polyviologen and the Ultra梀iolet spectrum of viologen cation radicals were studied and compared with that of butylviologen and benzylviologen The electron transfer from reductants (Na28204) to azobenzene using viologen polymers as electron梩ransfer catalysts (ETC) was studied. Results showed that the ETC abilities of the viologen polymers were affected by the following factors such as polymeric carrier , the length of the spacer linking the viologen group and the polymeric skeleton , the substituted group in viologen , the reaction medium(solvent) etc. The electron transfer catalytic abilities of viologen copolymer -5- di N?Y 梞ethacryloyloxypropyl--N - 梟--alkyl?,4 ?梑ipyridinium dibromide and acrylamide together with dimethylacrylamide were studied and compared with butylviologen.