Incorporating organic bulky cations in the precursor or post-treatment to achieve two-dimensional/thr ee-dimensional(2D/3D)heterojunction is an effective strategy for enhancing the stability of perovskite materials.Ho...Incorporating organic bulky cations in the precursor or post-treatment to achieve two-dimensional/thr ee-dimensional(2D/3D)heterojunction is an effective strategy for enhancing the stability of perovskite materials.However,the issue of insufficient charge transport in 2D perovskites limits their development,and the fundamental mechanism of out-of-plane carrier transport remains unclear.This study designed and synthesized seven organic phenyl-core cations,differentiated at the 1-and 1,4-positions,and identified the impacts on the corresponding properties of the 2D crystalline perovskite.Shorter cations facilitated a more compact arrangement of adjacent inorganic layers,aligning to favor charge transport along the vertical direction.In addition,introducing high electronegativity led to increased intermolecular interactions,resulting in enhanced structural stability and improved phenyl ring π-orbital overlap and interlayer electron coupling,yielding efficient charge transport.Resilience to thermal stressing of the perovskite was strongly correlated with the carbon chain length of the spacer cations.The increase in cation length and the reduction in the rigidity of the amino-terminal both aided in the dispersion of thermal stress in the inorganic framework.Additional hydrogen bonding also contributed to mitigating structural disorder.展开更多
基金financially supported by the Key Fund Project of Tianjin Natural Science Foundation(24JCZDJC00510)the Fundamental Research Funds for the Central Universitiespartially supported by the U.S.Department of Energy under Contract No.DE-AC3608GO28308 with Alliance for Sustainable Energy,Limited Liability Company(LLC),the Manager and Operator of the National Renewable Energy Laboratory,through Grant No.DE-SC0020718。
文摘Incorporating organic bulky cations in the precursor or post-treatment to achieve two-dimensional/thr ee-dimensional(2D/3D)heterojunction is an effective strategy for enhancing the stability of perovskite materials.However,the issue of insufficient charge transport in 2D perovskites limits their development,and the fundamental mechanism of out-of-plane carrier transport remains unclear.This study designed and synthesized seven organic phenyl-core cations,differentiated at the 1-and 1,4-positions,and identified the impacts on the corresponding properties of the 2D crystalline perovskite.Shorter cations facilitated a more compact arrangement of adjacent inorganic layers,aligning to favor charge transport along the vertical direction.In addition,introducing high electronegativity led to increased intermolecular interactions,resulting in enhanced structural stability and improved phenyl ring π-orbital overlap and interlayer electron coupling,yielding efficient charge transport.Resilience to thermal stressing of the perovskite was strongly correlated with the carbon chain length of the spacer cations.The increase in cation length and the reduction in the rigidity of the amino-terminal both aided in the dispersion of thermal stress in the inorganic framework.Additional hydrogen bonding also contributed to mitigating structural disorder.