FAPbI3 has been extensively employed in high-performance perovskite solar cells(PSCs)owing to its optimal bandgap and outstanding optoelectronic properties.Nevertheless,it readily undergoes the formation of a photo-in...FAPbI3 has been extensively employed in high-performance perovskite solar cells(PSCs)owing to its optimal bandgap and outstanding optoelectronic properties.Nevertheless,it readily undergoes the formation of a photo-inactiveδ-phase during crystallization,and achieving high-qualityα-phase films becomes even more challenging in antisolvent-free fabrication processes.This study introduces a crystallization control strategy based on 2-dimethylaminopyridine(2-DMAP)ligand engineering to establish a“fast nucleation-slow growth”dual-time-domain crystallization mechanism.2-DMAP facilitates the formation of a functional intermediate phase(2-DMAP·PbI_(2)·DMSO)that enables a direct transformation to theα-FAPbI3 phase and effectively suppresses theδ-phase pathway.Theoretical calculations and systematic experimental characterizations demonstrate that 2-DMAP exhibits stronger binding affinity and a greater charge polarization effect than dimethylsulfoxide(DMSO).This promotes the formation of high-density nuclei during spin coating and delays excessive grain growth during annealing,leading to perovskite films with improved crystallinity,fewer defects,and longer carrier lifetimes.As a result,an antisolvent-free PSC device was successfully fabricated,achieving a power conversion efficiency(PCE)of 25.10%,one of the highest reported for antisolvent-free spin-coating systems.Under ISOS-L-1 standard conditions,the device retained 84.78%of its initial efficiency after 1500 h of continuous illumination,demonstrating excellent operational stability.Moreover,it exhibited remarkable long-term stability under harsh humid and thermal conditions.This work offers a valuable strategy for the large-scale fabrication of high-performance and antisolvent-free PSCs.展开更多
基金supported by the National Natural Science Foundation of China(62374104,62374103)the Taishan Scholar Foundation of Shandong Province(tsqn2023120051105)+2 种基金the Natural Science Foundation of Shandong Province(ZR2023QE321)the Shandong University-Muerhls Joint LaboratoryThe authors also appreciate the analysis help from the Analytical Center for Structural Constituent and Physical Property of Core Facilities Sharing Platform,Shandong University,for the femtosecond transient absorption spectroscopy system(TAS,2104573S).
文摘FAPbI3 has been extensively employed in high-performance perovskite solar cells(PSCs)owing to its optimal bandgap and outstanding optoelectronic properties.Nevertheless,it readily undergoes the formation of a photo-inactiveδ-phase during crystallization,and achieving high-qualityα-phase films becomes even more challenging in antisolvent-free fabrication processes.This study introduces a crystallization control strategy based on 2-dimethylaminopyridine(2-DMAP)ligand engineering to establish a“fast nucleation-slow growth”dual-time-domain crystallization mechanism.2-DMAP facilitates the formation of a functional intermediate phase(2-DMAP·PbI_(2)·DMSO)that enables a direct transformation to theα-FAPbI3 phase and effectively suppresses theδ-phase pathway.Theoretical calculations and systematic experimental characterizations demonstrate that 2-DMAP exhibits stronger binding affinity and a greater charge polarization effect than dimethylsulfoxide(DMSO).This promotes the formation of high-density nuclei during spin coating and delays excessive grain growth during annealing,leading to perovskite films with improved crystallinity,fewer defects,and longer carrier lifetimes.As a result,an antisolvent-free PSC device was successfully fabricated,achieving a power conversion efficiency(PCE)of 25.10%,one of the highest reported for antisolvent-free spin-coating systems.Under ISOS-L-1 standard conditions,the device retained 84.78%of its initial efficiency after 1500 h of continuous illumination,demonstrating excellent operational stability.Moreover,it exhibited remarkable long-term stability under harsh humid and thermal conditions.This work offers a valuable strategy for the large-scale fabrication of high-performance and antisolvent-free PSCs.
