Synthesis Of Carbon-precious Metal Nanocomposites And Its Application In Portable Nitroaromatic Explosives Sensors

In recent years,terrorist bombings have occurred frequently around the world,and various forms of explosives and explosive devices have been used in terrorist criminal activities,causing a large number of casualties and property losses.Nitroaromatic explosives are the most widely used explosives currently.The related compounds and their degradation products emitted during the explosion also cause serious pollution to the environment and cause harm to human health.Therefore,analyzing and detecting nitroaromatic explosives by physical,chemical and other technological is great significance not only for preventing and combating terrorist crimes,but also for maintaining international peace and development,for monitoring and preventing environmental pollution,and for maintaining the survival of animals and plants,and keeping human health.Compared with the commonly used detection methods,electrochemical detection has the advantages of short detection time,simple operation,low cost and high sensitivity.However,the commonly used electrochemical testing equipment does not meet the requirements of environmental and safety testing for the portability of the device,which greatly limits its application in actual actual testing.Therefore,it is of great significance to develop a portable electrochemical detection platform with high sensitivity and low cost of nitroaromatic explosives.This paper designs and implements an portable electrochemical detection platform for nitroaromatic explosives based on intelligent electronic devices.The electrochemical detection platform uses the intelligent electronic devices?tablet computers?which are widely used currently as mobile terminals for command input,detection control,result display and data processing,and uses the portable electrochemical workstation to reduce the size of the instrument,and uses the screen printed electrode to replace the traditional three-electrode system,which simplifies the circuit design and reduces the overall cost of the electrochemical detection system.Then,a variety of nanocomposites were designed to functionalize the screen printing electrode,and it was applied in the quantitative analysis of nitroaromatic explosives.Furthermore,the nitroaromatic electrochemical detection platform was applied to the actual environmental testing to verify the possibility of its practical application.This paper is divided into four parts:Chapter 1:this part introduces the background,significance and methods of explosives detection,and summarizes the research progress of nitroaromatic explosives detection from two aspects of testing equipment and materials.Based on this,the paper puts forward the idea of the topic.Chapter 2:the screen-printed electrodes modified by Pd NFs-CNTs-GNSs three-dimensional porous nanomaterials were designed,and the quantitative detection of various nitroaromatic explosives was realized by electrochemical detection system based on intelligent electronic equipment.The nitroaromatic compounds is detected by the oxidation of a nitroaromatic compound molecule on the surface of the electrode to generate an electrical signal.In this paper,the three-dimensional skin-skeleton nanostructures constructed by two-dimensional nanomaterials GNS and one-dimensional nanomaterials CNTs.And modifying palladium nanoflowers on the skin-skeleton structure surface.The CNTs-GNSs skeleton structure not only has good electron transport ability,but also has excellent adsorption capacity for nitroaromatic compounds through?-?interaction.Palladium nanoflowers can efficiently catalyze the reduction of nitroaromatic compounds on the electrode surface.In this paper,Pd NFs-CNTs-GNSs are modified on the surface of screen-printed electrodes,and can sensitive and fast detect of variety of nitroaromatic compounds?TNT,TNB,DNT,DNB,Cl-DNB,4-NP?by a portable electrochemical detection platform.Its detection limit for TNT is 32.4n M,and the sensitivity is 4.30?A?M^-1 cm^-2,and the linear range is 100 n M-20?M.It can complete the quantitative detection of various nitroaromatic compounds in the actual natural environment.Chapter 3:the Pd-CNT-Ti₃C₂T_x three-dimensional nanocomposites were designed to achieve high-precision quantitative detection of various nitroaromatic explosives.So far,there are few reports on the application of Ti₃C₂T_x in the field of electrochemical sensing.In this work,Ti₃C₂T_x was innovative applied in the field of nitroarene electrochemical,and designed Pd-CNT-Ti₃C₂T_x three-dimensional nanocomposites.In-situ growth of CNTs on the surface of Ti₃C₂T_x by Pd nanoparticles catalysis can prevent the agglomeration of Ti₃C₂T_x and CNTs and increase the specific surface area,electrochemical active sites,electron transport capacity,adsorption capacity of Ti₃C₂T_x-CNTs substrates.And palladium nanoparticles bound to the top of the CNT can efficiently catalyze the reduction of nitroaromatics.Therefore,the material can achieve ultra-sensitive,rapid and convenient detection of various nitroaromatic compounds?TNT,TNB,DNT,DNB,Cl-DNB?,and has good stability and reproducibility.The detection limit for TNT is2.28 n M,the sensitivity is 43.36?A?M^-1 cm^-2,and the linear range is 10 n M-10?M.Chapter 4:Conclusion and Outlook.This chapter summarizes the research work of this paper,that mainly expounds the design and implementation of the electrochemical detection platform based on intelligent electronic equipment,and the application of the detection platform in the detection of nitroaromatic explosives.Finally,The problems existing in the work were analyzed objectively,and the future work was prospectively prospected from the improvement of testing equipment and the design of testing materials.