Study On The Synthesis And Properties Of Metal Hexadecafluorophthalocyanines

Organic semiconductor material is an important part of the field-effect transistors,and its properties directly affect the mobility of the OTFTs devices. To date, most ofthe organic semiconductor materials are the p-type materials, while the n-type organicsemiconductor materials are relatively rare. However, the n-type organicsemiconductor materials are the important part of pn junction diodes, bipolartransistors and complementary CMOS circuits. Therefore, the development of n-typeorganic semiconductor materials has a very significant. Phthalocyanine compoundswith18π electron conjugated structure and good thermal stability and easy to vacuumdeposition film are good semiconductor materials for the preparation of organic thinfilm transistors. In this thesis, the p-type metal phthalocyanine semiconductorsmaterials will be transformed into the n-type organic semiconductors by theintroduction of containing-F substituent, and these n-type materials will be applied inOTFTs.First, the tetrafluorophthalonitrile is synthesized using tetrafluorophthalicanhydride as a raw material by imidization, ammonification and dehydration reactionand the synthetic process is optimized. In optimum conditions, the total yield oftetrafluorophthalonitrile is46.71%and the purity is98.83%. The single crystal oftetrafluorophthalonitrile is obtained and its structure is analyzed. The crystal isattributed to orthorhombic system and its space group is P2₁2₁2₁.The seven kinds of metal hexadecafluorophthalocyanines MPcF₁₆（M=Fe、Co、Ni、Cu、Zn、VO and SnCl₂） were synthesized using tetrafluorophthalonitrile and metalsalts as raw materials through the liquid and solid state reaction and their structurewere characterized by IR, UV-Vis and MALDI-TOF-MS.The UV-vis absorption and fluorescence emission spectra of the target productwere studied. The maximal absorption peaks in the range of665⁷16nm was obtainedin the o-dichlorobenzene solutions, while the maximal absorption wavelength ofmetal hexadecafluorophthalocyanines in N, N-dimethylformamide was at654⁷02nm.With the polarity of solution enhanced, the UV-vis absorption spectrum blue-shifted,and molecular aggregation behavior occurred in a polar solvent. The maximumemission peak of metal hexadecafluorophthalocyanine in o-dichlorobenzene were at680⁷50nm. The fluorescence quantum of Zinc hexadecafluorophthalocyanine was0.67. Thermal analysis showed that the weight loss temperatures of metalhexadecafluorophthalocyanine were higher and their thermal stability was good. Cyclic voltammetry measurement showed that these compounds had LUMO energyvalue in the range of-4.64^-4.57eV, which is conducive to electron injection andmatching to the work function of the metal electrodes Au, such as the preparationn-channel field-effect devices may be provided. These properties indicate thatperfluorinated metal phthalocyanine can be candidates for the application in OTFTs asorganic semiconductor materials.Metal hexadecafluorophthalocyanines were applied in OTFTs by weak epitaxialfilm-forming technology, and high quality semiconductor thin films were obtained.The phthalocyanine molecules were approximately standing-up on the inducing layerand their intermolecular π-π conjugated direction was parallel to the base due to theintroduction of p-6p inducing layer. Devices prepared in this thesis, the field-effectmobility of OTFTs based on CuPcF₁₆is reach to0.07cm2/v s.