Ahn, Jihoon Ma, Sunihl Kim, Ji-Young Kyhm, Jihoon Yang, Wooseok Lim, Jung Ah Kotov, Nicholas A. Moon, Jooho 2024-01-19T18:01:52Z 2024-01-19T18:01:52Z 2021-09-05 2020-03-04 0002-7863 https://pubs.kist.re.kr/handle/201004/118865 The effect of chemical-composition modification on the chiroptical property of chiral organic ammonium cation-containing organic inorganic hybrid perovskite (chiral OIHP) is investigated. Varying the mixing ratio of bromide and iodide anions in S- or R-C6H5CH2(CH3)NH3)(2)PbI4(1-x)Br4x modifies the band gap of chiral OIHP, leading to a shift of the circular dichroism (CD) signal from 495 to 474 nm. However, it is also found that an abrupt crystalline structure transition occurs, and the CD signal is turned off when iodide-determinant phases are transformed into the bromide-determinant phase. To obtain CD in the wavelength range where the bromide-determinant phase is supposed to exhibit chiroptical activity, that is, <474 nm, S- or R-C12H7CH2(CH3)NH3 with a larger spacer group can be adopted; thus, the CD signal can be further blue-shifted to similar to 375 nm. Here, we show that chemical-composition modification of chiral OIHP affects the chiroptical properties of chiral OIHP in two ways: (1) tuning the wavelength of CD by modulating the excitonic band structure and (2) switching the CD on and off by inducing a crystalline-structure change. These properties can be utilized for structural engineering of high-performance chiroptical materials for spin-polarized light-emitting devices and polarization-based optoelectronics. English AMER CHEMICAL SOC HALIDE PEROVSKITES NANOPARTICLES SPECTRUM Chiral 2D Organic Inorganic Hybrid Perovskite with Circular Dichroism Tunable Over Wide Wavelength Range Article 10.1021/jacs.9b11453 1 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, v.142, no.9, pp.4206 - 4212 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 142 9 4206 4212 scie scopus 000518700800018 2-s2.0-85080139582 Chemistry, Multidisciplinary Chemistry Article HALIDE PEROVSKITES NANOPARTICLES SPECTRUM circular dichroism perovskite organic inorganic hybrid