Preparation Of Novel N-doped Carbon Nanomaterials And Their Applied Basic Research

In this thesis,the filling and compressing methods were used to prepare anodes respectively and N-doped carbon nanomaterials were prepared by DC arc discharge under hyperthermal N₂ atmosphere.The morphology,phase and elemental compositions,element bonding state,and optical properties of the products were characterized by using FESEM,TEM,HRTEM,XRD,EDX,EELS and UV-vis,respectively.The effects of the intake temperature of nitrogen and placed positions of the stainless steel sheets on the morphology,structure,and content of nitrogen of the N-doped carbon nanomaterials were investigated.Besides,the repeatability of the experiment was also investigated.The mechanism of formation of the N-doped hollow carbon spheres?NDHCSs?was discussed briefly.NDHCSs were prepared by DC arc discharge,using the anode prepared by filling method under nitrogen of 800?.The outer diameters of the NDHCSs are between 110 nm and 543 nm and their wall thicknesses are in the range of 2–12 nm.The walls consist of two parts,i.e.,the inner part is the comparatively complete structure of graphite and the outside one is the discontinuously wave-like structure of layer.The NDHCSs consist of C,N and O elements.There are three bonding types between N and C,i.e.,pyridine-like,pyrrole-like and graphite-like configurations.The phase composition of NDHCSs mainly includes graphitic carbon and another carbon phase.The UV-vis spectra of the suspensions of the NDHCSs in ethanol show three absorption peaks at 210 nm,221 nm and 264 nm respectively.Such suspension emits green luminescence under the irradiation of UV light.The compositions of anode,the gradients of temperature and concentration in the discharge chamber play important role on the morphology,wall thickness,composition and sizes of the NDHCSs.The placed positions of the stainless steel sheets have certain influence on the morphology of the deposits.They also have certain impact on the uniformity of the deposits and the content of nitrogen,but there is no obvious regularity.The intake temperature of nitrogen has obvious impact on the morphology of the products deposited on the stainless steel sheets.The higher the intake temperature of nitrogen is,the more diversifications the morphology have.In addition,the intake temperature of nitrogen also has influence on the content of nitrogen in the products.The higher the intake temperature of nitrogen is,the higher the content of nitrogen is.The products prepared by DC arc discharge are diversified.Some of the products?A^F?collected at the different positions in the arc discharge chamber have the similar morphology,but others have different morphology.The conditions of the different experiments have little influence on the morphology of products?A^F?collected at the different positions in the arc discharge chamber.The experiments have good repeatability.The results of this thesis have importantly practical and theoretical significance to prepare novel N-doped carbon nanomaterials by DC arc discharge and explore their potential applications.