Study On Preparation Of Low-dimensional Nano-carbon By Constrained Electro-explosive Graphite

The preparation of nano-materials by electric explosion method has the advantages of high energy utilization rate,precise control of process parameters,high purity of prepared products,and environmental protection.The electric explosion method was first used to make some metal wires into nano-powders,such as Cu,Mo,Al,etc.,and for some materials that are difficult to make into silk,they can only be electrically exploded in the form of powder.In this paper,a self-developed electric blasting device was used to conduct continuous electrical explosion test on graphite slurry prepared by proportioning graphite powder and lubricating oil in argon atmosphere.The method of preparing low-dimensional nano-carbon by constraining electric explosive graphite was studied..Based on the research results of the research group on electric explosion,this paper developed and designed a set of low-dimensional nano-carbon equipment for constrained electric explosive graphite.The equipment is composed of a high-voltage charging and discharging system,a constrained electric explosion device and a vacuum system.The working principle is as follows: the motor transmits power to the reciprocating screw through the coupling.Driven by the reciprocating scre w,the moving electrode on the carrier block pushes the restraining tube into the constraining hole.When the moving electrode moves to a proper position,the gas gap between the electrode and the graphite slurry is broken by a high voltage,and a large pu lse current is introduced into the graphite slurry and an electric explosion occurs in the restraining tube.The electric explosive product is suspended in the electric explosion chamber in the form of an aerosol.In the test,a very thin thermosetting epo xy resin was spin-coated on a polished copper substrate to sample the aerosol after electric explosion.This method can collect the original appearance of the electric explosion product and ensure sampling evenly distributedThe effects of initial charging voltage and constrained tube diameter on the morphology of electric explosion products were studied.The morphology of the electric explosion products was analyzed by scanning electron microscopy and transmission electron microscopy.The results show that there are nano-scale flakes,granular structures and a small number of micron-scale flakes in the electric explosive products.Under the condition that the diameter of the constrained tube is constant,with the increase of the initial charging voltage,th e nanostructure in the electric explosive product changes from thick to thin,from sheet to ellipsoid,and at 10 kV.The smaller Nano-carbon structure was found.Combined with the analysis of the current and voltage signals collected during the electric bla st,it is found that as the initial charging voltage increases,the energy density deposited on the graphite slurry also increases.In the test,the morphology of the electric explosion products prepared by the constrained tubes under the initial charging voltage was analyzed.The analysis shows that with the decrease of the diameter of the constrained tube,the proportion of nanostructures in the electric explosion product gradually increases,and the nanostructure in the product re-fines with the increase of the initial charging voltage.By analyzing the maximum air pressure generated in the constrained tube during the electric blasting process,it is considered that the pressure volume effect generated during the electric blasting process can increase the injection speed of the product and aggravate the collision between the electric blast products to nano-nitride the product.