Synthesis And Properties Of Small-molecule Organic Field-effect Transistor Containing Tetrathiafulvalene Groups

Organic field-effect transistor(OFET) is an very important device of organic electronics devices. OFETs have attracted great interest in organic electronics due to their special advantages of low-cost, large-scale yield, mechanical flexibility, high performance, etc. Their applications include use in integrated circuits, displays, electronic papers, radio frequency identification (RFID) tags, sensors, storage devices, etc. Recent development of new organic semiconductors and processing techniques have achieved high-performance OFETs with field-effect mobility (FET) higher than 1.0 cm2 V-1 s-1. TTF and its derivatives, as electron donors in organic charge-transfer(OCT) materials or organic radical salts, have been intensively investigated in the field of organic conductors and superconductors. On the other hand, TTF derivatives have some good features for acting as semiconducting layers in OFETs. In this paper, the main purpose is to the design and synthesize novel TTF derivatives for OFETs. The main research contents are as follows:1. We designed and synthesized a series of benzene-fused bis-TTF small molecules bearing electron-withdrawing alkoxycarbonyl group, the π-conjugated benzene-fused bis-TTF backbone is a basically planar configuration with very small interplanar twist angles. Their oxidation potentials determined by cyclic voltammetry were shifted cathodically by more than 0.20 eV. This strategy indeed brought many useful changes, such as thermal stability, HOMO energies level, packing structure. Their oxidation potentials determined by cyclic voltammetry were shifted cathodically by more than 0.20 eV compared with the alkylthio group substituted analogues, the best performing device exhibited a hole mobility up to 0.057 cm2V-1s-1 under ambient conditions.2. We designed and synthesized a series of T-shaped organic conjugates,on both of its pyridazine on the basis of the introduction of benzene ring increased different ability of electron-donating and electron-withdrawing group material of small molecule 7a-7c. There HOMO and LUMO energy levels were work out to be respectively in the range from-4.88～-5.04 eV and-3.74～-3.9 eV, which suggest that this series of compounds may be used as organic semiconductor. But it is a pity that in the aspect of its device test showed a poor performance...