Investigation of Chemical Origin of White-Light Emission in Two-Dimensional (C4H9NH3)2PbBr4 via Infrared Nanoscopy

Dae Young Park; Sung-Jin An; Chanwoo Lee; Duc Anh Nguyen; Kang-Nyeoung Lee; Mun Seok Jeong

doi:10.1021/acs.jpclett.9b03328

Investigation of Chemical Origin of White-Light Emission in Two-Dimensional (C₄H₉NH₃)₂PbBr₄ via Infrared Nanoscopy

J Phys Chem Lett. 2019 Dec 19;10(24):7942-7948. doi: 10.1021/acs.jpclett.9b03328. Epub 2019 Dec 11.

Authors

Dae Young Park¹, Sung-Jin An^{1

2}, Chanwoo Lee^{1

2}, Duc Anh Nguyen¹, Kang-Nyeoung Lee¹, Mun Seok Jeong^{1

2}

Affiliations

¹ Department of Energy Science , Sungkyunkwan University , Suwon 16419 , Republic of Korea.
² Center for Integrated Nanostructure Physics (CINAP) , Institute for Basic Science (IBS) , Suwon 16419 , Republic of Korea.

PMID: 31813216
DOI: 10.1021/acs.jpclett.9b03328

Abstract

The broadband light emission in low-dimensional organic lead halide perovskites (OHPs) is a fascinating property for white light-emitting diodes (LEDs). However, unique emission has been observed in highly distorted low-dimensional OHPs such as (110) and (111) perovskites. Herein, we report the first observation of white-light emission under ambient (21 °C) conditions in a rectangular microsheet of (C₄H₉NH₃)₂PbBr₄, a (100) perovskite. The origin of white-light emission in (C₄H₉NH₃)₂PbBr₄ was revealed as defect-assisted radiative recombination via excitation power-dependent photoluminescence measurement. Additionally, the origin of the defect was confirmed to be organic cation vacancies formed by intercalated water molecules via infrared nanoscopy. This result can help to improve the performance of white LEDs using low-dimensional OHPs.