Circularly polarized electroluminescence from chiral supramolecular semiconductor thin films

• 成果类型: Article
• 署名作者: Chowdhury, Rituparno; Preuss, Marco D.; Cho, Hwan-Hee; Thompson, Joshua J. P.; Sen, Samarpita; Baikie, Tomi K.; Ghosh, Pratyush; Boeije, Yorrick; Chua, Xian Wei; Chang, Kai-Wei; Guo, Erjuan; van der Tol, Joost; van den Bersselaar, Bart W. L.; Taddeucci, Andrea; Daub, Nicolas; Dekker, Daphne M.; Keene, Scott T.; Vantomme, Ghislaine; Ehrler, Bruno; Meskers, Stefan C. J.; Rao, Akshay; Monserrat, Bartomeu; Meijer, E. W.; Friend, Richard H.
• 署名单位: University of Cambridge; Eindhoven University of Technology; Eindhoven University of Technology; University of Cambridge; University of Cambridge; University of Cambridge; University of Cambridge; Huazhong University of Science & Technology; Diamond Light Source; University of Pisa; AMOLF; Yonsei University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13785
• DOI: 10.1126/science.adt3011
• 发表日期: 2025-03-14
• 页码: 1175-1181
• 关键词: viscoelastic phase-separation; light-emitting-diodes; spin selectivity; room-temperature; dichroism; polymers

摘要

Current organic light-emitting diode (OLED) technology uses light-emitting molecules in a molecular host. We report green circularly polarized luminescence (CPL) in a chirally ordered supramolecular assembly, with 24% dissymmetry in a triazatruxene (TAT) system. We found that TAT assembled into helices with a pitch of six molecules, associating angular momentum to the valence and conduction bands and obtaining the observed CPL. Cosublimation of TAT as the guest in a structurally mismatched host enabled fabrication of thin films in which chiral crystallization was achieved in situ by thermally triggered nanophase segregation of dopant and host while preserving film integrity. The OLEDs showed external quantum efficiencies of up to 16% and electroluminescence dissymmetries >= 10%. Vacuum deposition of chiral superstructures opens new opportunities to explore chiral-driven optical and transport phenomena.