The Research Of Tetra(4-pyridyl)porphyrin Charge-Transfer Compounds With Photoelectric Properties

Porphyrin compounds exist widely in nature. Because of their unique structure, performance and special physiological activities, porphyrins have been applied in the field of materials chemistry, medicine, biochemistry, synthetic chemistry, analytical chemistry and energy. In most cases, porphyrins and metalloporphyrin complexes usually act as electron donors in D-A ensembles. Such properties can be tuned as electron acceptors by introducing strongly electron-withdrawing substituents, high-valent metal ions, and protons to the macrocycles. Tetrathiafulvalene(TTF) and its derivatives have attracted great interest for a long time due to the unique donor and redox properties and have been used in many areas, such as supramolecular chemistry, conductor, semiconductor, superconductor materials, biological sensors, chemical sensors and macrocyclic chemistry. In recent years, germanium chalcogenide materials also have been a hot research topic due to its application in the field of catalysis, ion exchange, and its potential application in semiconductor, nonlinear optics. In this thesis, tetrakis-(N-methyl-4-pyridinium)-porphyrin is used as the research object to study the charge-transfer properties through introducing TTF-carboxylate,(Ge4S10)4-, and metal manganese ion into the system. It mainly includes the following contents:In introduction, properties and research progress of porphyrins reviewed briefly. The applications of porphyrins in photo-voltaic materials and energy utilization were summarized. Research progress of TTFs in molecular devices and photo-voltaic materials were introduced. Besides, the applications in optical, electrical fields of charge transfer compounds were reviewed briefly. Finally, the significance and the main contents of the thesis are introduced.In chapter 2, two {[cation]n+·[TTFs]n–} ion pair charge-transfer complexes: {TMPyP-(HL1)4}?3H2O(1) and {TMPyP-(H2L2)2}?5H2O(2) were synthesized based on TTF carboxylate anion and(TMPyP)4+ cation. The strong ionic interaction enhances the charge-transfer between the regular mixed-stacking donors and acceptors, which are investigated comprehensively by spectral, electrochemical and theoretical studies. The variation in properties between L1 and L2 is of great advantage to understand the influence factors for charge-transfer. The charge-transfer properties can be modulated not only by the nature of the donor or the acceptor, but also the cation-anion ratio in the salt, which shows great flexibility of the D-A ionic dyad in the design and preparation of new charge-transfer systems.In chapter 3, compound {TMPyP-Ge4S10}?3H2O(3) was obtained through the assembly of(TMPyP)4+ with the functional anion(Ge4S10)4-. Single-crystal X-ray structural analysis shows that anion(Ge4S10)4- is sanwiched by the cation(TMPyP)4+. A significant charge-transfer absorption band can be observed in UV-vis spectra. Furthermore, a manganese coordination compound [Mn2(PyP)Cl3]?CHCl3?H2O(4) with PyP ligand was prepared. Crystal structure and optical properties of compound 4 have been investigated. The results show that fluorescence quenching occurs due to the energy transfer between molecules.