Excited-State Modulation for Controlling Fluorescence and Phosphorescence Pathways toward White-Light Emission

doi:10.1002/adom.201900767

CORC > 化学研究所 > 中国科学院化学研究所

	Excited-State Modulation for Controlling Fluorescence and Phosphorescence Pathways toward White-Light Emission
	Feng, Changfu; Li, Shuai; Xiao, Xiaoxiao; Lei, Yilong; Geng, Hua; Liao, Yi; Liao, Qing; Yao, Jiannian; Wu, Yishi; Fu, Hongbing
刊名	ADVANCED OPTICAL MATERIALS
	2019-08-02
ISSN号	2195-1071
DOI	10.1002/adom.201900767
英文摘要	Luminescence originated from singlet (S-1) and triplet (T-1) states is categorized as fluorescence and phosphorescence, respectively. Modulation of fluorescence and phosphorescence pathways plays a central role in developing organic luminescent materials, but remains difficult because of the lack of control ways. Here, luminescence of cocrystals of 1,7-phenanthroline (PR) and 1,4-diiodotetrafluorobenzene (DITFB) can be switched by adjusting their stoichiometry, from bluish fluorescence for 1:0 pure PR crystal (P1D0) to yellowish phosphorescence for 1:1 PR:DITFB cocrystal (P1D1). More importantly, 2:1 PR:DITFB cocrystal (P2D1) is found to exhibit dual fluorescence and phosphorescence simultaneously, thus giving rise to white-light emission. Experimental and time-dependent density-function-theory results reveal that although the S-1 and T-1 energies keep invariable, high-lying T-n states introduced in cocrystals decreases the S-1-T-n energy gap, meanwhile multiple intermolecular halogen bonding enhances the spin-orbital coupling. As a result, the S-1 -> T-n intersystem crossing rate (k(ISC)) is accelerated by 2 orders of magnitude, making k(ISC) comparable and faster than the fluorescence decay rate k(Fl) for P1D0 (fluorescence), P2D1 (dual emissions), and P1D1 (phosphorescence), respectively. The results provide not only a quantum-mechanical understanding but also a novel strategy to modulate the excited-state dynamics toward fluorescence and/or phosphorescence emissions for luminescent materials.
语种	英语
WOS记录号	WOS:000478972200001
内容类型	期刊论文
源URL	[http://ir.iccas.ac.cn/handle/121111/82686]
专题	中国科学院化学研究所
作者单位	Chinese Acad Sci, Inst Chem, Beijing 100190, Peoples R China
推荐引用方式 GB/T 7714	Feng, Changfu,Li, Shuai,Xiao, Xiaoxiao,et al. Excited-State Modulation for Controlling Fluorescence and Phosphorescence Pathways toward White-Light Emission[J]. ADVANCED OPTICAL MATERIALS,2019.
APA	Feng, Changfu.,Li, Shuai.,Xiao, Xiaoxiao.,Lei, Yilong.,Geng, Hua.,...&Fu, Hongbing.(2019).Excited-State Modulation for Controlling Fluorescence and Phosphorescence Pathways toward White-Light Emission.ADVANCED OPTICAL MATERIALS.
MLA	Feng, Changfu,et al."Excited-State Modulation for Controlling Fluorescence and Phosphorescence Pathways toward White-Light Emission".ADVANCED OPTICAL MATERIALS (2019).