Carbon Dot Functionalized Papers for the Selective Detection of 2,4,6-Trinitrophenol in Aqueous Solutions

The development of probes for the testing of the carcinogenic pollutant 2,4,6-trinitrophenol (TNP) is of great importance for environmental protection and human health. In this paper, a new rapid and sensitive fluorescence detection method based on carbon dots (CDs) was designed for the detection of TNP. The CDs were synthesized by simple pyrolysis using citric acid as raw material and characterized by various advanced techniques. The addition of TNP caused a significant turn off in the fluorescence of the CDs. The fluorescence quench intensity and TNP concentration exhibited a good linear correlation in the range of 0–80 μM with a minimum detection limit of 0.48 μM and a related coefficient of 0.994. The analytical method was applied to the determination of trace TNP in river water and tap water with recoveries in the range of 98%–110% and relative standard deviations less than 5%. Importantly, carbon dots functionalized papers (CDFPs) were prepared using the synthesized CDs and successfully applied to the determination of TNP in aqueous solutions, demonstrating the promising application of the method.