Investigation of thermal parameters of AlN nanoparticles at the different heating rates

Abstract

Heat flux and mass change of AlN nanoparticles at the different heating rates were considered as a function of temperature. The Gibbs energy of the AlN nanoparticles system was determined in the temperature range of 300 ÷ 1400K, at the heating rates as 5, 10, 15 and 20 K/min. Experiments in heating and cooling processes were carried out separately and the results were analyzed. The surface oxidation process under the influence of temperature is formed AlxNyOz compound, which is explained by phonon oscillations on the Raman spectrum. The hydroxide effect on crystallization and properties of the material is clear on the Raman spectrum. Simultaneously, on the surface of nanoparticles Al(OH)3 or AlOOH are formed as a result of the hydration, and phonon oscillations are observed. Moreover, as a result of the temperature effect, VN and VAl3−−3×ON+ defect complexes can be formed in the sample. Space symmetry of AlN nanoparticles and preserving the crystalline structure at the nanoscale were investigated by the XRD method. The size and surface imaging of nanoparticles were studied using HRTEM analyses.