Highly stable CsPbBr3/ PMA perovskite nanocrystals for improved optical performance

Purusottam Reddy Bommireddy; Jagadeesh Babu B; Sreedhar Sunku; Kamal Basha C; Youngsuk Suh; Chandra Sekhar M; Si-Hyun Park

doi:10.1016/j.heliyon.2024.e24497

Highly stable CsPbBr₃/ PMA perovskite nanocrystals for improved optical performance

Heliyon. 2024 Jan 12;10(2):e24497. doi: 10.1016/j.heliyon.2024.e24497. eCollection 2024 Jan 30.

Authors

Purusottam Reddy Bommireddy¹, Jagadeesh Babu B², Sreedhar Sunku², Kamal Basha C³, Youngsuk Suh¹, Chandra Sekhar M², Si-Hyun Park¹

Affiliations

¹ Department of Electronic Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan-si, Gyeongsanbuk-do, South Korea.
² Department of Physics, Madanapalle Institute of Technology and Science, Madanapalle, 517325, India.
³ Department of Electrical and Electronics Engineering, Madanapalle Institute of Technology and Science, Madanapalle, 517325, India.

Abstract

In this study, to address the stability issues, we synthesized a CsPbBr₃-coated poly (maleic anhydride-alt-1-octadecene) (CsPbBr₃/PMA) using a modified hot-injection method. The CsPbBr₃/PMA perovskite nanocrystals (PNCs) exhibited effective green emission at 522 nm with an improved photoluminescence quantum yield (86.8 %) compared to traditional CsPbBr₃ PNCs (54.2 %). The ligands in the polymer coating can bond with the uncoordinated Pb and Br ions on the surface of PNCs to minimize surface defects and avoid exposure to the external environment, enhancing the stability of the perovskites. Time-resolved photoluminescence spectra showed longer lifetimes for CsPbBr₃/PMA PNCs, while transient absorption measurements provided valuable insights into the intraband hot-exciton relaxation and recombination. We demonstrate the potential application of CSPbBr₃/PMA in a down-conversion white-light-emitting diode (LED) by coupling green CsPbBr₃/PMA and red K₂SiF₆:Mn⁴⁺ phosphor-coated glass slides onto a 455-nm blue GaN LED. The white LED produced a white light with the International Commission on Illumination color coordinates of (0.323, 0.345), luminous efficiency of 58.4 lm/W, and color rendering index of 83.2. The fabricated, white-LED system obtained a wide color gamut of 125.3 % of the National Television Standards Committee and 98.9 % of Rec. 2020. The findings demonstrate that CsPbBr₃/PMA can be an efficient down-conversion material for white LEDs and backlighting.

Keywords: Nanocomposites; Optical materials/properties; Perovskite nanocrystals.