All-inorganic CsPbIBr2perovskite solar cells(PSCs)have attracted considerable research attention in recent years due to their excellent thermal stability.However,their power conversion efficiencies(PCEs)are relatively...All-inorganic CsPbIBr2perovskite solar cells(PSCs)have attracted considerable research attention in recent years due to their excellent thermal stability.However,their power conversion efficiencies(PCEs)are relatively low and still far below the theoretical limit.Here,we report the use of an organic dye molecule(namely VG1-C8)as a bifunctional interlayer between perovskite and the hole-transport layer in CsPbIBr2PSCs.Combined experimental and theoretical calculation results disclose that the multiple Lewis base sites in VG1-C8 can effectively passivate the trap states on the perovskite films.Meanwhile,theπ-conjugated dye molecule significantly accelerates the hole extraction from the perovskite absorber as evidenced by the photoluminescence analysis.Consequently,the VG1-C8 treatment simultaneously boosts the photovoltage and photocurrent density values from 1.26 V and 10.80 mA cm^(-2) to 1.31 V and 12.44 m A cm^(-2),respectively.This leads to a significant enhancement of PCE from 9.20%to12.10%under one sun irradiation(AM 1.5G).To our knowledge,this is the record efficiency reported so far for CsPbIBr_(2) PSCs.Thus,the present work demonstrates an effective interfacial passivation strategy for the development of highly efficient PSCs.展开更多
基金the financial support by the National Natural Science Foundation of China(52161145408 and21975038)the Fundamental Research Funds for the Central Universities(DUT20RC(3)085)。
文摘All-inorganic CsPbIBr2perovskite solar cells(PSCs)have attracted considerable research attention in recent years due to their excellent thermal stability.However,their power conversion efficiencies(PCEs)are relatively low and still far below the theoretical limit.Here,we report the use of an organic dye molecule(namely VG1-C8)as a bifunctional interlayer between perovskite and the hole-transport layer in CsPbIBr2PSCs.Combined experimental and theoretical calculation results disclose that the multiple Lewis base sites in VG1-C8 can effectively passivate the trap states on the perovskite films.Meanwhile,theπ-conjugated dye molecule significantly accelerates the hole extraction from the perovskite absorber as evidenced by the photoluminescence analysis.Consequently,the VG1-C8 treatment simultaneously boosts the photovoltage and photocurrent density values from 1.26 V and 10.80 mA cm^(-2) to 1.31 V and 12.44 m A cm^(-2),respectively.This leads to a significant enhancement of PCE from 9.20%to12.10%under one sun irradiation(AM 1.5G).To our knowledge,this is the record efficiency reported so far for CsPbIBr_(2) PSCs.Thus,the present work demonstrates an effective interfacial passivation strategy for the development of highly efficient PSCs.
