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Four organic small-molecule hole transport materials (D41,D42,D43 and D44) of tetraarylpyrrolo[3,2-b]pyrroles were pre-pared.They can be used without doping in the manufacture of the inverted planar perovskite solar cells.Tetraarylpyrrolo[3,2-b]pyrroles are accessible for one-pot synthesis.D42,D43 and D44 possess acceptor-π-donor-π-acceptor structure,on which the aryl bearing substitutes of cyan,fluorine and trifluoromethyl,respectively.Instead,the aryl moiety of D41 is in presence of methyl with a donor-π-donor-π-donor structure.The different substitutes significantly affected their molecular surface charge distribution and thin-film morphology,attributing to the electron-rich properties of fused pyrrole ring.The size of perovskite crystalline growth particles is affected by different molecular structures,and the electron-withdrawing cyan group of D42 is most conducive to the formation of large perovskite grains.The D42 fabricated devices with power conversion efficiency of 17.3% and retained 55% of the initial photoelectric conversion efficiency after 22 days in dark condition.The pyrrolo[3,2-b]pyrrole is efficient electron-donating moiety for hole transporting materials to form good substrate in producing perovskite thin film.