Highly efficient NIR-Ⅱ window photoluminescence up to 1000 nm using heteroatomic fused-ring radicals

Jun-Yang Hui; Hai-Ping Zhou; Ying Sun; You-Liang Li; Qing-Qing Pan; Yu-He Kan; Zhong-Min Su

doi:10.1016/j.saa.2024.125592

Highly efficient NIR-Ⅱ window photoluminescence up to 1000 nm using heteroatomic fused-ring radicals

Spectrochim Acta A Mol Biomol Spectrosc. 2024 Dec 16:329:125592. doi: 10.1016/j.saa.2024.125592. Online ahead of print.

Authors

Jun-Yang Hui¹, Hai-Ping Zhou², Ying Sun¹, You-Liang Li¹, Qing-Qing Pan³, Yu-He Kan⁴, Zhong-Min Su⁵

Affiliations

¹ School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Jilin Provincial Science and Technology Innovation Center of Optical Materials and Chemistry, Jilin Provincial International Joint Research Center of Photo-functional Materials and Chemistry, Changchun 130022, China.
² State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130021, China.
³ School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Jilin Provincial Science and Technology Innovation Center of Optical Materials and Chemistry, Jilin Provincial International Joint Research Center of Photo-functional Materials and Chemistry, Changchun 130022, China. Electronic address: panqq349@nenu.edu.cn.
⁴ Jiangsu Province Key Laboratory for Chemistry of Low-Dimensional Materials, School of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an 223300, China. Electronic address: kyh@hytc.edu.cn.
⁵ School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Jilin Provincial Science and Technology Innovation Center of Optical Materials and Chemistry, Jilin Provincial International Joint Research Center of Photo-functional Materials and Chemistry, Changchun 130022, China; State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130021, China. Electronic address: zmsu@nenu.edu.cn.

PMID: 39689546
DOI: 10.1016/j.saa.2024.125592

Abstract

Neutral radicals have the potential to construct pure organic light-emitting diodes (OLEDs) with internal quantum efficiencies reaching 100%. However, neutral radical luminescent materials with emission wavelengths in the second near-infrared (NIR-II) window are rare. Herein, a serial of neutral donor-bridge-acceptor (D-π-A) type radical derivatives are investigated. The dominant elements influencing the luminescent properties of neutral radicals, such as chemical stability, excited state characteristics, radiative decay rate (k_r) and internal conversion rate (k_IC) constants are taken into consideration. Theoretical calculations reveal that introducing heteroatomic fused-rings into neutral radicals can modulate the chemical stability and result in a red shift of the emission wavelength spectrum. In the presence of charge transfer characteristics, by increasing the effective overlap between the hole and electron wavefunctions, the k_r constants of the neutral D-π-A type radicals increase. In addition, avoiding the geometric relaxation between the lowest excited state (D₁) and the ground state (D₀), as well as reducing electron-vibration coupling and non-adiabatic coupling in the low-frequency region can effectively decrease the k_IC constants. Our study proposes an innovative design approach aiming to develop stable and efficient NIR-II window neutral radical luminescent materials utilizing heteroatomic fused-rings as key elements.

Keywords: DFT/TD-DFT; Heteroatomic fused-rings; NIR-Ⅱ window; Neutral radicals; Photoluminescence quantum yield.