Influence of TiO₂ nanoparticles on the photovoltaic efficiency of the ITO/PEDOT:PSS/fluorine copolymers/polythiophene: TiO₂/Al architecture

Results of a study on the application of a copolymer of fluorine as acceptor and 1H-pyrazolo[3,4- b]quinoxaline as a donor in bulk heterojunction solar cells are given. To the best of our knowledge, 1H-pyrazolo[3,4- b]quinoxaline co-polymers were not applied in organic photovoltaic devices yet. Organic photovoltaic devices as well as devices of active layers with TiO ₂ nanocrystals of different crystallite size were investigated. The methods of polymer and TiO₂ nanocrystllites synthesis are presented and their physical properties are given. The fabricated photovoltaic structures possess high values of Uoc voltage as as well as relatively high parameters of Isc currents. The maximally achieved parameters corresponded to open circuit voltage Uoc = 1.13[V], and short current density Isc = 33.49[μA] under illumination 1,3 [μW cm^-2], which correspond to energy conversion efficiency equal to about 0.80 %. The TiO₂ nanocrystallites play a crucial role in the photovoltaics parameters.