气相沉积法制备均苯四甲酸二酰亚胺纳米材料及传感应用

摘要

以均苯四甲酸二酰亚胺(PMD)为原料,采用真空气相沉积法制得PMD纳米自组装材料,由此建立了测定三硝基甲烷的荧光化学传感新方法.采用真空气相沉积法自组装PMD纳米材料,并用扫描电镜、透射电镜、红外光谱、紫外光谱、差热分析及荧光光谱对材料进行了表征.扫描电镜图像显示,PMD纳米材料呈带状网络结构,长度为30 ～ 100 μm;TEM图像表明,PMD纳米带宽度为100 ～ 300 nm,其中纳米线直径为120 ～ 220nm.在PMD分子自组装过程中,分子间氢键、π-π等弱相互作用是构筑纳米结构的主要驱动力.一些较低沸点有机分子蒸汽对PMD纳米材料的荧光(λ./λem=377 nm/495 nm)有猝灭作用,尤其是PMD纳米材料对三硝基甲烷有灵敏的响应.测定三硝基甲烷的线性范围为2.19×10-5～ 1.37×10-4 mol/L,R2=0.995,检出限为1.02×10-6 mol/L.%Pyromellitic diimide(PMD) nanomaterial was prepared by vacuum vapor deposition and molecular self-assembly method using PMD as raw material.A new method for determination of trinitromethane was established by fluorescence chemical sensor.The properties of PMD nanomaterials synthesized by vacuum vapor deposition method were characterized by scanning electron microscopy,transmission electron microscopy,infrared spectroscopy,UV spectroscopy,differential thermal analysis and fluorescence spectroscopy.The scanning electron microscopy (SEM) results show that the PMD nanomaterial has a banding network with a length of 30-100 μm.TEM images show that the PMD nanobelts have a width of 100-300 nm,and the nanowires have a diameter of 120-220 nm.The main driving force for constructing the nanostructures of PMD in the self-assembly process is from the intermolecular hydrogen bonds and π-π weak interaction.The experiments show that some of the lower boiling organic molecules have a strong effect on the fluorescence quenching of PMD nanomaterials,especially trinitromethane does a sensitive response to PMD nanostructures.The linear range of trinitromethane is from 2.19 × 10-5 to 1.37 × 10-4 mol/L(R2 =0.995) with the detection limit of 1.02 × 10-6 mol/L.