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A great deal of attention has been paid tO the preparation and characterization of nanostructure. These materials have significant potential applications in many important advanced technologies, such as solar energy conversion, chemical sensor, catalysis, absorption and separation, and they also have some novel electrical, optical, magnetic and chemical properties. In this thesis, hexagonal AlN (h-AlN) nanopowders and nanowires were successfully synthesized by dc arc-discharge. On the other hand, producing AlN nanowires by means of sintering the nanopowders in high temperature.The morphology, chemical compositions, crystal structures and some properties of these obtained nanowires were systemically characterized, and the growth mechanism of AlN nanowire was also studied.Nanowire of nitride aluminum had been prepared by de arc-discharge in different conditions. We had investigated atmosphere, the gas pressure proportion and the power affluence on the low-dimensional A1N nanomaterial, and the composition, morphologies, microstructures were investigated. The result confirmed that the mixture of hydrogen and nitrogen with the pressure proportion of 1:1, the total pressure of 8×104pa, purity AlN nanopowders were obtained and in the others conditions the mixture of Al and AlN nanopowders were attained.With the increasing of power the yield of nanopowders was increasing, and in the atmospheres of nitrogen and ammonia the yield of nanopowders was the highest in the five atmospheres. In the atmospheres of nitrogen and ammonia, hexagonal A1N nanowires were successfully synthesized by dc arc-discharge. The diameter of hexagonal AlN nanowire distributed from 20 to ll0nm, and the maximum length was up to 20μm. Bending part is crystal without fault. Energy band structure of AlN nanowire resemble AlN nanopowder’s, which occur to blue shift and red shift.By mean of sintering of nanopowders in high temperature to produce AlN nanowires, we had investigated temperature, the keeping temperature time and raw material affluence on the A1N nanowires, and performance characterization of A1N nanowire was also studied. The result confirmed that the mixture of Al and AlN nanopowders were used as the raw material and at the temperature of 1130℃, the diameter of hexagonal AIN nanowires distributed from 20 to 100nm, and the maximum length was up to several tensμm. The result confirmed that the individual nanowire has the nature of single crystal and wurtzite structure, and the lattice parameter was a=3.11, c=5.08In the latter part of this paper, the growth mechanism of A1N nanowire was discussed primarily. According to the TEM, primary theorem of thermodynamics and learning from the former studies for the growth mechanism of one dimension nanometer material, the growth mechanism of A1N nanowires by dc arc-discharge is belong to VLS style, and in the sintering method which is attributed to SLS style.
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