Defects at the surface and grain boundaries of the perovskite films are extremely detrimental to both the efficiency and stability of perovskite solar cells(PSCs).Herein,a simple and stable quaternary ammonium halide,...Defects at the surface and grain boundaries of the perovskite films are extremely detrimental to both the efficiency and stability of perovskite solar cells(PSCs).Herein,a simple and stable quaternary ammonium halide,named chlormequat chloride(i.e.,chlorinated choline chloride,CCC),is introduced to regulate the upper surface chemical environment of perovskite films.The anion(Cl^(-))and cation[ClCH_(2)CH_(2)N(CH_(3))_(3)]+in CCC could effectively self-search and passivate positively and negatively charged ionic defects in per ovskites,respectively,which contributes to inhibited nonradiative recombination and reduced energy los in PSCs.As a result,the champion power conversion efficiency(PCE)of PSCs can be significantly enhanced from 22.82%to 24.07%.Moreover,the unencapsulated device with CCC modification retains 92.0%of it original PCE even subject to thermal aging at 85℃ for 2496 h.This work provides guidance for the ratio nal design of functional molecules as defect passivators in PSCs,which is beneficial for the improvement in both device performance and stability.展开更多
基金supported by the National Natural Science Foundation of China(No.21773218)and Huacai Solar Co.,Ltd.。
文摘Defects at the surface and grain boundaries of the perovskite films are extremely detrimental to both the efficiency and stability of perovskite solar cells(PSCs).Herein,a simple and stable quaternary ammonium halide,named chlormequat chloride(i.e.,chlorinated choline chloride,CCC),is introduced to regulate the upper surface chemical environment of perovskite films.The anion(Cl^(-))and cation[ClCH_(2)CH_(2)N(CH_(3))_(3)]+in CCC could effectively self-search and passivate positively and negatively charged ionic defects in per ovskites,respectively,which contributes to inhibited nonradiative recombination and reduced energy los in PSCs.As a result,the champion power conversion efficiency(PCE)of PSCs can be significantly enhanced from 22.82%to 24.07%.Moreover,the unencapsulated device with CCC modification retains 92.0%of it original PCE even subject to thermal aging at 85℃ for 2496 h.This work provides guidance for the ratio nal design of functional molecules as defect passivators in PSCs,which is beneficial for the improvement in both device performance and stability.
