Room-temperature phosphorescence and fluorescence nanocomposites as a ratiometric chemosensor for high-contrast and selective detection of 2,4,6-trinitrotoluene

Weili Kong; Meina Liu; Jinhui Zhang; Hongbo Wu; Yaqin Wang; Qin Su; Qin Li; Jun Zhang; Chengli Wu; Wen-Sheng Zou

doi:10.1016/j.aca.2023.341930

Room-temperature phosphorescence and fluorescence nanocomposites as a ratiometric chemosensor for high-contrast and selective detection of 2,4,6-trinitrotoluene

Anal Chim Acta. 2023 Nov 22:1282:341930. doi: 10.1016/j.aca.2023.341930. Epub 2023 Oct 17.

Authors

Weili Kong¹, Meina Liu¹, Jinhui Zhang¹, Hongbo Wu², Yaqin Wang³, Qin Su¹, Qin Li¹, Jun Zhang⁴, Chengli Wu⁵, Wen-Sheng Zou⁶

Affiliations

¹ School of Materials and Chemical Engineering, Key Laboratory of Functional Molecule Design and Interface Procedure, Anhui Jianzhu University, Hefei, 230022, China.
² School of Chemical Engineering, Anhui University of Science and Technology, Huainan, 232001, China.
³ School of Materials and Chemical Engineering, Key Laboratory of Functional Molecule Design and Interface Procedure, Anhui Jianzhu University, Hefei, 230022, China. Electronic address: yqwang@ahjzu.edu.cn.
⁴ School of Materials and Chemical Engineering, Key Laboratory of Functional Molecule Design and Interface Procedure, Anhui Jianzhu University, Hefei, 230022, China; New Energy Photovoltaic Industry Research Center, Qinghai University, Xining, 810016, China.
⁵ School of Chemical Engineering, Anhui University of Science and Technology, Huainan, 232001, China. Electronic address: chlwu@aust.edu.cn.
⁶ School of Materials and Chemical Engineering, Key Laboratory of Functional Molecule Design and Interface Procedure, Anhui Jianzhu University, Hefei, 230022, China. Electronic address: wszou@ahjzu.edu.cn.

PMID: 37923408
DOI: 10.1016/j.aca.2023.341930

Abstract

Reports on using complementary colours for high-contrast ratiometric assays are limited to date. In this work, graphitized carbon nitride (g-C₃N₄) nanosheets and mercaptoethylamine (MEA) capped Mn-doped ZnS QDs were fabricated by liquid exfoliation of bulk g-C₃N₄, and by a coprecipitation and postmodification strategies, respectively. Mn-doped ZnS quantum dots were deposited onto g-C₃N₄ nanosheets through an electrostatic self-assembly to form new nanocomposites (denoted as Mn-ZnS QDs@g-C₃N₄). Mn-ZnS QDs@g-C₃N₄ can emit a pair of complementary colour light, namely, orange room-temperature phosphorescence (RTP) at 582 nm and blue fluorescence at 450 nm. After 2,4,6-trinitrotoluene (TNT) dosing into Mn-ZnS QDs@g-C₃N₄ aqueous solution, and pairing with MEA to generate TNT anions capable of quenching the emission of Mn-doped ZnS QDs, the fluorescence colours of the solution changed from orange to blue across white, exhibiting unusual high-contrast fluorescence images. The developed ratiometric chemosensor showed very good linearity in the range of 0-12 μM TNT with a limit of detection of 0.56 μM and an RSD of 6.4 % (n = 5). Also, the ratiometric probe had an excellent selectivity for TNT over other nitroaromatic compounds, which was applied in the ratiometric test paper to image TNT in water, and TNT sensing under phosphorescence mode to efficiently avoid background interference. A high-contrast dual-emission platform for selective ratiometric detection of TNT was therefore established.

Keywords: 2,4,6-Trinitrotoluene (TNT); Complementary colours; High-contrast; Ratiometric assay; Room-temperature phosphorescence (RTP).