Carbon dots@metal–organic frameworks as dual-functional fluorescent sensors for Fe 3+ ions and nitro explosives

• Published in: CrystEngComm Vol. 23; no. 22; pp. 4038 - 4049
• Main Authors: Tao, Yufang, Jiang, Yansong, Huang, Yating, Liu, Junning, Zhang, Ping, Chen, Xiaodong, Fan, Yong, Wang, Li, Xu, Jianing
• Format: Journal Article
• Language: English
• Published: 09.06.2021
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/D1CE00392E

Carbon dots (CDs) with excellent optical properties were encapsulated into two fluorescent metal–organic frameworks (MOFs), namely, [Cd(HL)]·0.8H 2 O ( 1 ) and [Cd 3 (L) 2 ]·3H 2 O ( 2 ) (H 3 L = 4-(5-carboxypyridin-2-yl)isophthalic acid). The as-prepared CDs@ 1 and CDs+ 2 not only retained the strong fluorescence activity of CDs, but also embedded Eu 3+ ions in the hybrids to form dual-emitting Eu 3+ /CDs@ 1 and Eu 3+ /CDs+ 2 . These novel composites emitted strong red light at room temperature and exhibited good fluorescence sensing capabilities for Fe 3+ ions, p -nitrotoluene ( p -NT) and 2,4-dinitrophenol (2,4-DNP) in water solutions with detection limits of 0.034 μM, 0.0096 μM, 0.062 μM and 0.0111 μM. These results indicate that 1A and 2A (activated products of Eu 3+ /CDs@ 1 and Eu 3+ /CDs+ 2 ) could be regarded as potential dual-functional fluorescent sensors with superior sensitivity and excellent selectivity.