Studies On Preparation, Characterization Of Hybird LB Films Of Alkynylplatinum-zinc Porphyrinate/Heteropolyoxometalate And Covalently-linked Organic-polyoxometalates Hybrid Materials

A series of novel organic porphyrin derivative/polyacid(polyoxometalate,POM) hybrid LB films were prepared by Langmuir-Blodgett(LB) technique using several different structure polyoxometalates as inorganic composites, organic and organomet-allic porphyrin derivatives as organic composites. The forming film stability, structural and photoelectric properties of these LB films were characterized by π-A isotherms, absorption and photoluminescence spectra, atomic force microscopy imaging, scanning tunneling microscopy, and surface photovoltaic spectroscopy. In addition, a new organic-inorganic covalently linked hybrid was synthesized by using organic phosphate derivative as organic composite, Dawson type of phosphorus tungsten acid as inorgaic composite. The structural and photoelectric properties of these compounds were studied.Chapter Ⅰ Literature reviewThe chapter introduced the development and preparation of organic-inorganic hybrid materials. An overview of the polyacids, LB films, alkynylplatinum(Ⅱ) zinc(Ⅱ) porphyrinate were made, and organometallic porphyrin derivatives of Dawson type POM were described as well. The design idea on this research was proposed.Chapter Ⅱ Preparation, characterization and photoelectric properities of alkynylplatinum(Ⅱ) zinc(Ⅱ) porphyrinate/heteropolyoxometalate hybrid LB filmsUsing three kinds of the Keggin, Dawson, Anderson types of polyoxometalate as inorganic composites, alkynylplatinum(Ⅱ)zinc(Ⅱ) porphyrinate as organic composites, a new family of organic/inorganic hybrid LB films were prepared by LB technique. The structures, photoelectric properties and electric conductivity of these LB films were studied. The results showed that it can form a stable and ordered monolayer or multilayer films in gas-liquid interface. Because organic porphyrin contains π-conjugated system, which can be acted as the electron donor, the polyoxometalate can be acted as a good electron acceptor, electron and energy transfer in the π-conjugated system might be the main reason that result in the good electrical conductivity, quenching effect of luminescence and good photovoltaic responsibilty in the these covalently linked hybrids.Chapter Ⅲ Preparation, characterization and photoelectric properities of alkynylplatinum(Ⅱ)zinc(Ⅱ) porphyrinate/europium-substituted polyoxometalate hybrid LB filmsThe rare earth element of europium-substituted polyoxometalates as inorganic co-mposites, one porphyrin derivatives as organic composite, monolayer and multilayers LB films were prepared by LB technique. The structures, photoelectric properties and electric conductivity of these LB films were studied. The results showed that it can form a stable and ordered monolayer or multilayer films, because of the two composites can form the π-conjugated donor-acceptor-system, the LB films showed good photoelectric property.Chapter Ⅳ Preparation and characterization of organic-Dawson type polyoxometalate hybrid solidUsing the Dawson type polyoxometalate as inorganic composite, organphosphite derivatives as organic composites, two new covalently linked hybrid materials were synthesized. The structure and photoluminescence properties of the new hybrids were studied. The results show that the red shift of the emission was observed in the hybrid due to the longer conjugated chain in the system. In addition, we can infer that the polyoxometalate may accept some excited electrons from the organic conjugated system which results in the partly quenching effect of fluorescence in the hybird.