Light-induced photoluminescence enhancement in chiral CdSe quantum dot films

Yang Wang; Pan Liang; Yumeng Men; Meizhen Jiang; Lin Cheng; Jinlei Li; Tianqing Jia; Zhenrong Sun; Donghai Feng

doi:10.1063/5.0201365

Light-induced photoluminescence enhancement in chiral CdSe quantum dot films

J Chem Phys. 2024 Apr 28;160(16):161102. doi: 10.1063/5.0201365.

Authors

Yang Wang¹, Pan Liang², Yumeng Men¹, Meizhen Jiang¹, Lin Cheng¹, Jinlei Li¹, Tianqing Jia¹, Zhenrong Sun¹, Donghai Feng^{1

3}

Affiliations

¹ State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.
² College of Arts and Sciences, Shanghai Dianji University, Shanghai 201306, China.
³ Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China.

PMID: 38651809
DOI: 10.1063/5.0201365

Abstract

Chiral quantum dots (QDs) are promising materials applied in many areas, such as chiral molecular recognition and spin selective filter for charge transport, and can be prepared by facile ligand exchange approaches. However, ligand exchange leads to an increase in surface defects and reduces the efficiencies of radiative recombination and charge transport, which restricts further applications. Here, we investigate the light-induced photoluminescence (PL) enhancement in chiral L- and D-cysteine CdSe QD thin films, providing a strategy to increase the PL. The PL intensity of chiral CdSe QD films can be significantly enhanced over 100 times by continuous UV laser irradiation, indicating a strong passivation of surface defects upon laser irradiation. From the comparative measurements of the PL intensity evolutions in vacuum, dry oxygen, air, and humid nitrogen atmospheres, we conclude that the mechanism of PL enhancement is photo-induced surface passivation with the assistance of water molecules.