Efficient Red/Near‐Infrared‐Emissive Carbon Nanodots with Multiphoton Excited Upconversion Fluorescence

• Published in: Advanced science Vol. 6; no. 17; pp. 1900766 - n/a
• Main Authors: Liu, Kai‐Kai, Song, Shi‐Yu, Sui, Lai‐Zhi, Wu, Si‐Xuan, Jing, Peng‐Tao, Wang, Ruo‐Qiu, Li, Qing‐Yi, Wu, Guo‐Rong, Zhang, Zhen‐Zhong, Yuan, Kai‐Jun, Shan, Chong‐Xin
• Format: Journal Article
• Language: English
• Published: Germany John Wiley & Sons, Inc 01.09.2019; John Wiley and Sons Inc; Wiley
• Subjects: Automation; carbon nanodots; cellular imaging; Communication; Communications; Experiments; fluorescence; Fourier transforms; Lasers; Microscopy; Morphology; multiphoton excitation; NMR; Nuclear magnetic resonance; red/near‐infrared; Solvents; Spectrum analysis; carbon nanodots; red/near‐infrared; cellular imaging; multiphoton excitation; fluorescence
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.201900766

Red/near‐infrared (NIR) emissive carbon nanodots (CNDs) with photoluminescence (PL) quantum yield (QY) of 57% are prepared via an in situ solvent‐free carbonization strategy for the first time. 1‐Photon and 2‐photon cellular imaging is demonstrated by using the CNDs as red/NIR fluorescence agent due to the high PL QY and low biotoxicity. Further study shows that the red/NIR CNDs exhibit multiphoton excited (MPE) upconversion fluorescence under excitation of 800–2000 nm, which involves three NIR windows (NIR‐I, 650–950 nm; NIR‐II, 1100–1350; NIR‐III, 1600–1870 nm). 2‐Photon, 3‐photon, and 4‐photon excited fluorescence of the CNDs under excitation of different wavelengths is achieved. This study develops an in situ solvent‐free carbonization method for efficient red/NIR emissive CNDs with MPE upconversion fluorescence, which may push forward the application of the CNDs in bioimaging. Red/near‐infrared (NIR) emissive carbon nanodots (CNDs) with photoluminescence quantum yield of 57% are demonstrated via an in situ solvent‐free strategy. 1‐Photon and 2‐photon cellular imaging is demonstrated. Furthermore, multiphoton excited red/NIR fluorescence of the CNDs is achieved.