In this thesis we synthesize two organic materials, one is discotic liquid crystal Acid-6, and the other is novel discotic liquid crystal polymer DLC-PAM. After demonstrating the molecular structures of Acid-6 and DLC-PAM by FT-MS, 1H-NMR and FT-IR, we use the two materials as photo-sensitized dyes for dye-sensitized solar cells(DSSCs) and manufacture two kinds of cells. We use polyacrylamide(PAM) as main chain of the novel discotic liquid crystal polymer DLC-PAM and graft the discotic liquid crystal monomer Acid-6 onto PAM by chemical synthesis. DLC-PAM belongs to side-chain liquid crystal polymer, and it can show the properties of it¡¦s discotic liquid crystal function. One of the properties is absorption of visible light. By observing the UV-Vis spectrum, we can realize the absorption band is located between 200 ~ 450 nm and confirm that it is able to be a photo-sensitized dye. Another property of discotic liquid crystal is the self-assembly ability, the moleculars can assemble into hexagonal columnar structure by themselves, and the property enable discotic liquid crystal to have better mobility. In this part, we can demonstrate DLC-PAM and Acid-6 really have hexagonal columnar structure by X-ray diffractmeter. After qualitative demonstrating and optical analysis, we use DLC-PAM and Acid-6 as photo-sensitized dyes for DSSCs and manufacture two kinds of cells successfully. The more photocurrent occur when the two DSSCs are woking. Besides, the two DSSCs have good performance on power conversion efficiency which can achieve 0.047 % for DLC-PAM and 0.364 % for Acid-6. Therefore, in this research we prove that DLC-PAM and Acid-6 are able to be photo-sensitized dyes for DSSCs and successfully demonstrate that using the two materials to manufacture DSSCs is feasible.

We proposed a flexible electronics with functional poly (arylene ether)s and discotic liquid crystal. Firstly, we provided a series of the PAE polymer with remarkable thermal stability and high optical transmittance. The PAEs were synthesized via nucleophilic displacement as polymerization on a 2-trifluoromethyl-activated bisfluoro monomer, which reacted with bisphenols. Thermal analysis indicated the PAEs possessed a high glass transition point of ~300¢J and the decomposition temperature Td=500¢J at a weight loss of 5%. Additionally, high transmittance of 85%, low dielectric constant of ~2.0, and well mechanical property of the PAE films were experimentally verified, as a high potential substrate for flexible electronics. Two kind of device structure has been prepared, were organic thin film solar cell and Dye sensitized solar cell. Furthermore, we provided the self-assembled triphenylene-based liquid crystal and its polymer derivative to apply for photovoltics. The 2, 3, 6, 7-tetra-6-octyloxydibenzo[a,c]phenazine-11-carboxylic group and the polymer of merging with disc-unit and polyacrylamide. Both show a highly isotropic phase transition point of ~270¢J and the decomposition temperature Td~450¢J at a weight loss of 5%. The specific absorption in visible light region was at 200 - 450 nm. A distinct self-arrangement of columnar array was investigated by optical textures. The self-arranged pathway enhanced carrier mobility due to £k-£k conjugation in hexagonal column stacking. Finally, the PAEs and DLC materials applied to thin film solar cell (ITO/PEDOT:PSS/DLC-PAM/P3HT:PCBM/Al) as hole transporting layer. The photo-conversion efficiency was strong depending on organic compounds, such as molecular structure, photo-physic and chemical properties. On the basis of integrated characteristics, it suggested a high potential as flexible electronics for photovoltics.

We take 5,6,11,12,17,18-hexaaztrinaphthylene and dibenzo[a,c]phenazine as our central core that with dove-tailed side chains. It is shown that the size-related increase of steric interactions among the peripheral side chains substituted to the aromatic core leads to a dramatically lowered isotropization temperature.

In this PhD thesis, there are two major motifs: dibenzo[a,c]phenazine- and 2,3-diphenylquinoxaline novel discogens and fluorous polycatenar liquid crystals. The thermo properties of these new compounds were elucidated using optical microscopy, differential scanning calorimetry and powder X-ray diffraction. In the phenanthroline series (Chapter 2), 1,10-phenanthroline core incorporated into dibenzo[a,c]phenazine structure exhibit columnar mesophases with extremely wide width. X-ray diffraction study pinpoints to that half-shaped mesogens with reduced symmetry has preferential intra-molecular parallel conformation in the mesophase. This molecule has gel ability with different solvents. In dimeric crown ether series (Chapter 3A), 2,3-diphenylquinoxaline-based mesogens containing dibenzo-18-crown-6 has hexagonal columnar mesophase with extremely narrow width. Incorporation potassium metal ion into crown moiety dramatically enhanced mesomorphic stability and for metal complexes, as side chain increases, hexagonal mesophases predominate over rectangular mesophases. Furthermore, both in hexagon or rectangle, per columnar slice consist of two molecules. All of prolonged long glassy formation up to one year at room temperature. In monomeric crown ether series (Chapter 3B), metal-free molecules fail to be mesomorphic, but complexation with lithium and sodium metals enhanced thermo stability and rectangular mesophase (C2mm) were found. Also, per columnar slice was comprised of four molecules. Last (Chapter 4), a series of tri- and tetra-catenar mesogens containing various combinations of hydrocarbon and semiperfluorocarbon chains has been prepared to elucidate the fluorophlic-fluorophobic effect on mesomorphism. Tricatenar with one terminal semiperfluoro- and two hydrocarbon chains are aligned into lamellar periodicity driven by the mutual incompatibility of the hydrocarbon and fluorocarbon portions. But unsymmetric tetracatenar mesogens show rectangular mesophase.

Discotic liquid crystals (DLC) have been reported with a large number of discoid cores to improve the degree of intermolecular ordering because the liquid crystals own to self-assembly into columnar stacking and self¡Vhealing ability. In my research, a series of disc-like £k-conjugated molecules based on aromatic rigid cores have been newly synthesized. I focus on the hexaazatrinaphthylene (HATN) and dibenzo-[a,c]- phenazine as aromatic cores, changing different side chains to control the mesomorphic behavior and their supermolecular assembly.

Unsymmetrical discotic liquid crystals based on hexaazatriphenylene(HAT) have not been published until today.We have used tetrahydoxyquinone as the starting material to synthesis unsymmetrical discotic liquid crystals based on HAT and investigate their properties of liquid crystal.

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