ABSTRACT
Three new azomethines based on triphenylamine with two or three substituents were obtained. Chemical structure and purity were confirmed by 1H NMR, FTIR elemental analysis and mass spectroscopy. The investigations were focused on the relationship between chemical structure and properties important for optoelectronic materials. Thus, the studies of thermal, optical and electrochemical properties were carried out based on differential scanning calorimetry, thermogravimetric analysis, electronic absorption, photoluminescence and cyclic voltammetry measurements. The ongoing consideration of experimental results was complemented by theoretical calculations using the density functional theory method. The donor activity of obtained compounds was tested in bulk-heterojuntion photovoltaic cells with structure ITO/PEDOT:PSS/imine:PCBM/Al and ITO/PEDOT:PSS/imine:P3HT:PCBM/Al). The effect of the presence of the amino-thiophene-3,4-dicarboxylic acid diethyl ester groups and various number of hexyloxyphenyl units on imines properties was demonstrated.
ABSTRACT
Third-generation solar cells, including dye-sensitized solar cells, bulk-heterojunction solar cells, and perovskite solar cells, are being intensively researched to obtain high efficiencies in converting solar energy into electricity. However, it is also important to note their stability over time and the devices' thermal or operating temperature range. Today's widely used polymeric materials are also used at various stages of the preparation of the complete device-it is worth mentioning that in dye-sensitized solar cells, suitable polymers can be used as flexible substrates counter-electrodes, gel electrolytes, and even dyes. In the case of bulk-heterojunction solar cells, they are used primarily as donor materials; however, there are reports in the literature of their use as acceptors. In perovskite devices, they are used as additives to improve the morphology of the perovskite, mainly as hole transport materials and also as additives to electron transport layers. Polymers, thanks to their numerous advantages, such as the possibility of practically any modification of their chemical structure and thus their physical and chemical properties, are increasingly used in devices that convert solar radiation into electrical energy, which is presented in this paper.
