The porphyrin derivatives, 5,10,15,20-tetra(4-(N-pentane-carboxamide) phenyl) porphyrin(4 NC5-TPP), 5,10,15,20-tetra(4-(N-dodecane-carboxamide) phenyl) porphyrin(4 NC12-TPP) and their zinc-complexes(4 NC5-TPPZn and 4 NC12-TPPZn), have been synthesized. Their thermal properties and morphologies were investigated via thermal gravity analysis(TGA), differential scanning calorimetry(DSC) and polarized optical microscopy(POM). It was found that the 4 NC5-TPP was amorphous and the 4 NC5-TPPZn was crystalline at room temperature, while the 4 NC12-TPP formed the columnar liquid crystal and the 4 NC12-TPPZn showed the spherulite texture. The electron state density distributions and the optimum configuration of the porphyrin derivatives were calculated by chemical simulation. The electrochemical oxidation and reduction abilities of the porphyrin derivatives were studied by cyclic voltammetry(CV). It was indicated that the porphyrin derivatives had the potential to develop organic photovoltaic(OPV) devices. Using the porphyrin derivatives as donor materials and the 3,4,9,10-perylenetetracarboxylic dianhydride(PTCDA) as the acceptor material, the OPV devices were fabricated. The device structure is ITO/porphyrin derivatives:PTCDA/Al. The relationship between the morphology and performance of OPV was studied. It was found that the crystalline morphology of the film was beneficial to improve the efficiency of the devices.
For the purpose of developing flexible organic photovoltaic devices, we have fabricated two flexible devices using 5-formyl- 2,20:50,200:500,2000-quaterthiophene (4T-CHO), 5-formyl-2,20:50, 200:500,2000:5000,20000-quinquethiophene (5T-CHO) and 3,4,9,10-peryle- netertracarboxylic dianhydride (PTCDA). The PET-ITO/4T-CHO/PTCDA/Al device has an open circuit voltage (Voc) of 1.56 V, photoelectric conversion efficiency of 0.77%. The PET-ITO/5T-CHO/PTCDA/Al device has a Voc of 1.70 V, photoelectric conversion efficiency of 0.84%. The two flexible devices have high Voc (1.56 and 1.70 V). It is possible that intermolecular hydrogen bonding between-CHO group of nT-CHO and carboxylic dianhydride of PTCDA contributes to enhancing the efficiency by promoting interfacial electron transfer and eliminating the subconducting band trap sites.
Ping LiuTu Hua ChenWan Zhang PanMing Sheng HuangWen Ji DengYu Liang MaiAn Bo Luan
The water-soluble conjugated polyelectrolyte, poly[3-(1′-ethyloxy-2′-N- methylimidazole)thiophene](PEOIMT), was prepared. Its photophysical and electrochemical properties, and response characteristics to the external condition(e g, temperature response, solvent response and pH response), were investigated. The results show the PEOIMT belongs to the organic semiconductor. The interaction between the PEOIMT and the bovine serum albumin(BSA) was investigated using UV-vis spectroscopy. It was found that the PEOIMT could interact with the BSA. The PEOIMT can be used as a biosensor to detect the BSA.
For the purpose of developing organic photovoltaic devices with good performance characteristics,we have fabricated twodevices using 4T-CHO,5T-CHO and PTCDA.The ITO/4T-CHO/PTCDA/Al device has a V_oc of 2.45 V and photoelectricconversion efficiency of 2.76%.The ITO/5T-CHO/PTCDA/Al device has a V_oc of 2.1 3V and photoelectric conversion efficiency of2.90%.The two devices have higher Voc(2.45 and 2.13 V).It is possible that intermolecular hydrogen bonding between-CHOgroup of nT-CHO and carboxylic dianhydride of PTCDA contribute to enhance the efficiency by promoting interfacial electrontransfer and eliminating the subconducting band trap sites.
Ping LiuJia Le HuangWan Zhang PanMing Sheng HuangWen Ji DengYu Liang MaiAn Bo Luan