TY - JOUR
T1 - Impact of Halogen Groups on the Properties of PEA-Based 2D Pb–Sn Halide Perovskites
AU - Foadian, Elham
AU - Sanchez, Sheryl L.
AU - Harris, Sumner B.
AU - Lawrie, Benjamin J.
AU - Dubey, Astita
AU - Tang, Yipeng
AU - Hu, Bin
AU - Yang, Jonghee
AU - Ahmadi, Mahshid
N1 - Publisher Copyright:
© 2025 Wiley-VCH GmbH.
PY - 2025
Y1 - 2025
N2 - Tuning broad emission in 2D Pb–Sn halide perovskites (HPs) is essential for advancing optoelectronic applications, particularly for color-tunable and white-light-emitting devices. This broad emission is linked to structural factors, such as defects and phase segregation of the Pb component within the Pb–Sn system, which are strongly influenced by the molecular structure and chemical properties of spacer cations. Atomic tuning of the spacers via halogenation opens up a new way to fine-tune the molecular properties, enabling further augmentations of HP functionalities. Nevertheless, the distinct broad emission's sensitivity to spacer chemistry remains underexplored. Here, halogenation's influence is systematically investigated on 2D HP emission characteristics using a high-throughput workflow. These findings reveal that the F-containing phenethylammonium (4F-PEA) spacer narrows the broadband PL, whereas Cl broadens it. Through a correlative study, it is found that 4F-PEA reduces not only the local phase segregation but also the defect levels and microstrains in 2D HPs. This is likely attributed to the manifestation of less lattice distortion via stronger surface coordination of the dipole-augmented 4F-PEA. These results highlight halogenation as a key factor in modulating phase segregation and defect density in 2D Pb–Sn HPs, offering a promising pathway to tune the emission for enhanced optoelectronic performance.
AB - Tuning broad emission in 2D Pb–Sn halide perovskites (HPs) is essential for advancing optoelectronic applications, particularly for color-tunable and white-light-emitting devices. This broad emission is linked to structural factors, such as defects and phase segregation of the Pb component within the Pb–Sn system, which are strongly influenced by the molecular structure and chemical properties of spacer cations. Atomic tuning of the spacers via halogenation opens up a new way to fine-tune the molecular properties, enabling further augmentations of HP functionalities. Nevertheless, the distinct broad emission's sensitivity to spacer chemistry remains underexplored. Here, halogenation's influence is systematically investigated on 2D HP emission characteristics using a high-throughput workflow. These findings reveal that the F-containing phenethylammonium (4F-PEA) spacer narrows the broadband PL, whereas Cl broadens it. Through a correlative study, it is found that 4F-PEA reduces not only the local phase segregation but also the defect levels and microstrains in 2D HPs. This is likely attributed to the manifestation of less lattice distortion via stronger surface coordination of the dipole-augmented 4F-PEA. These results highlight halogenation as a key factor in modulating phase segregation and defect density in 2D Pb–Sn HPs, offering a promising pathway to tune the emission for enhanced optoelectronic performance.
KW - 2D Pb–Sn halide perovskites
KW - defects
KW - halogenation of spacer cation
KW - high-throughput experiments
KW - phase segregation
UR - http://www.scopus.com/inward/record.url?scp=85214527099&partnerID=8YFLogxK
U2 - 10.1002/adom.202403120
DO - 10.1002/adom.202403120
M3 - Article
AN - SCOPUS:85214527099
SN - 2195-1071
JO - Advanced Optical Materials
JF - Advanced Optical Materials
ER -