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During the past decade,the power conversion efficiencies(PCEs)of organic-inorganic hybrid perovskite solar cells(PSCs)have exceeded 25%[1],which is expected to be one of the candidates for the next generation of thin-film pho-tovoltaic technology.Fundamentally speaking,the perfor-mance of PSCs mainly depends on the light absorption capacity,defect passivation and photo-induced exciton se-paration and extraction of perovskite films.Under the light illumination,photo-induced excitons were separated and extracted by the built-in electric field of PSCs.Un-fortunately,relatively small built-in electric fields do not provide enough driving force to completely separate the excitons and allow the captured charge to escape from the deep-level defect states[2,3].In this process,the non-ra-diative recombination of perovskites caused by internal and surface defects,especially deep-level defects,may become a serious recombination center,which is unfavorable to pho-togenerated electrons and holes,resulting in significant en-ergy loss[4].Therefore,the enhancement of the built-in electric field to promote the separation and transportation of electrons and holes,and the passivation of defects to reduce the non-radiation recombination has important significance for the efficient PSCs.