Piezochromic luminescence of dicoronylene: Key for revealing hidden Raman modes at high pressure. (September 2022)

• Record Type: Journal Article
• Authors: Nakagawa, Takeshi; Dalladay-Simpson, Philip; Bu, Kejun; Guo, Songhao; Vrankić, Martina; Wang, Dong; Sereika, Raimundas; Zhang, Jianbo; Zhang, Caoshun; Hu, Qingyang; Lü, Xujie; Ding, Yang; Mao, Ho-kwang
• Is Part Of: Carbon. Volume 197(2022)
• Page Start: 563
• Page End: 569
• Publication Date: 2022-09
• Subjects: Polycyclic aromatic hydrocarbons -- Fluorescence -- Piezochromism -- Raman spectroscopy -- High pressure; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2022.06.009
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: Molecular crystals of dicoronylene (C48 H20 ), a member of very large polycyclic aromatic hydrocarbons (PAHs), exhibits strong red fluorescence under ambient conditions. This strong fluorescence induced by visible light excitation obscures entire Raman spectrum of dicoronylene. We employed in-situ high-pressure photoluminescence spectroscopy to observe a reversible piezochromic effect, in which the fluorescence exhibits a drastic red-shift with a rapid quenching of intensity. Above 4 GPa, under red-shifted and reduced fluorescence, hidden Raman modes are observed with 532 nm green laser up to 20 GPa. In this work, we show that the application of pressure can finely tune the fluorescence of dicoronylene, allowing the observation of the Raman spectrum with an appropriate laser wavelength and we discovered that dicoronylene has high chemical stability among PAH molecules with multiple aromatic rings. Graphical abstract: Image 1 Highlights: Systematically investigated structure-property relation of C48 H20 at high pressure. Piezochromic luminescence behaviour of C48 H20 from visible to near-IR range. Piezochromic behaviour reveals the Raman modes of C48 H20 at high-pressure. High-pressure IR and XRD revealed C48 H20 high stability and reversibility.