Construction And Applied Study Of Nano-colorimetric Methods For Three Kinds Energetic Materials

Many toxic substances will be produced in the preparation and use process of energizing materials.Hence,it's significant to detection of energizing materials.Nano-colorimetric sensors make full use of the unique optical properties of nanomaterials,combing with the simplicity of traditional colorimetric methods,has become an important direction for the development of energetic materials.Based on the it,we did some works as follows:?1?Cya-Ag NPs have been produced by reduction in aqueous solution.The Cya-Ag NPs possess a strong surface plasmon resonance?SPR?at around 418 nm.Significantly,the SPR absorption increased and the peak blue-shifted to 410 nm with a color change from red-yellow to bright yellow in the presence of N₂H₄.These changes can be attributed to the oxidative dissolution of Ag NPs by dissolved O2 in solution due to the nucleophilicity of N₂H₄.Under the optimal experimental conditions,the relative absorbance is proportional to the logarithm of concentration of N₂H₄ in the range of 0.01-40 ?M with a correlation coefficient of 0.993.The detection limit was calculated to be 0.01 ?M based on a signal-to-noise of 3,and the detection limit was 10 ?M by nake eyes.Moreover,this assay also can be potentially useful for selective and sen sitive trace N₂H₄ in real water with good recovery and accuracy.?2?The cysteine-protected molybdenum disulfide nanosheets?Cys-MoS₂ NSs?,obtained from sonication-assisted exfoliation of bulk MoS₂ crystals,possess a great intrinsic peroxidase-like activity for the oxidation of 3,3,5,5-tetramethylbenzidine?TMB?by hydrogen peroxide?H₂O₂?to produce a blue-colored solution.Based on this finding,we proposed a colorimetric assay to trace H₂O₂ in solution with a wide linear range with a correlation coefficient of 0.995,and the detection limit was calculated to be 0.01 ??,and the detection limit was 16 ?? by nake eyes.Moreover,this assay also can be potentially useful for selective and sensitive trace N₂H₄ in real water with good recovery and accuracy.?3?A facile colorimetric assay for 2,4,6-trinitrotoluene?TNT?in aqueous solution based on the intrinsic peroxidase-like activity Cys-MoS₂ NSs is proposed.The oxidation of TMB was weakened or even prevented in the presence of TNT because of the formation of Meisenheimer complex between TNT and TMB,which results in a decrease in the absorbance and a color change of Cys-MoS₂-TMB-H₂O₂ solution?TMB reaction system?tremendously.The relative absorbance is proportional to the logarithm of concentration of TNT in the range of 0-50 ?M with a correlation coefficient of 0.994,and the detection limit was calculated to be 0.01 ??,and the detection limit was 2.5 ?M by nake eyes.Moreover,this assay for TNT is also applicable to the real water samples with good recovery and accuracy.