Photostable and Low-Toxic Yellow-Green Carbon Dots for Highly Selective Detection of Explosive 2,4,6-Trinitrophenol Based on the Dual Electron Transfer Mechanism

Abstract

Advances in the development of fluorescent carbon dots (CDs) for detecting nitro-explosives have attracted great interest. However, developing long-wavelength luminescence CDs for highly selective determination of 2,4,6-trinitrophenol (TNP) and getting insight into the detection mechanism remain further to be investigated. Here, excitation-independent yellow-green emission CDs with good photostability and low biotoxicity were introduced for detecting TNP selectively. Then, two types of electron transfer (ET) processes including hydrogen-bond interaction-assisted ET and proton transfer-assisted ET are suggested to be responsible for their photophysical behavior. Finally, the visual detection of TNP has been successfully developed by a CD-based indicator paper. The facile, highly sensitive, and selective detection for TNP in both of a solution and a solid phase makes CDs potentially useful in environmental sensor applications.

A stable pillared metal–organic framework constructed by H4TCPP ligand as luminescent sensor for selective detection of TNP and Fe3+ ions

“…Furthermore, TNP was most efficiently detected probably because it has three nitro functional groups. As the NO 2 group of the nitro explosive increases, electron transfer becomes easier, which leads to efficient fluorescence quenching …”

Recent advance of carbon dots in bio-related applications

“…Based on these unique optical properties, fluorescent CDs are great potential candidates for fluorescent bioimaging. In addition, CDs also exhibit great potential on the sensor for ions [23][24][25] and (bio)molecules [26][27][28] and antibacterial materials, which introduced the positively charged quaternary ammonium groups or silver nanoparticles [29][30][31][32][33]. In this review, we are focusing on the fluorescent carbon dots used for fluorescent probes for bioimaging and related multiple function composites for biological applications.…”

Biogreen Synthesis of Carbon Dots for Biotechnology and Nanomedicine Applications

“…The group attributed the fluorescence quenching of CDs in the presence of TNP to IFE. More recently, Ju et al [ 235 ] investigated the quenching mechanism of CDs in the presence of TNP. The group proposed that the fluorescence quenching of CDs after the addition of TNP is attributed to electron transfer processes, which include hydrogen-bonding-assisted electron transfer and proton-assisted electron transfer.…”