Synthesis of InN nanoparticles by rapid thermal ammonolysis

AIII group nitrides have attracted a great deal of attention in the last decades due to their applications in modern microelectronic and optoelectronic devices. In this paper, simple and controllable methods for a synthesis of InN nanoparticles in the form of nanodisks and skeletal nanostructures are presented. Careful control of the experimental conditions is necessary, as the thermal stability of InN at elevated temperatures is low. The morphology of nanoparticles was investigated by scanning electron microscopy and transmission electron microscopy combined with selected area diffraction. Profile analysis of powder X-ray diffraction data shows that the apparent size of the crystals along [001] direction decreases from the size larger than 100 nm for the low temperature syntheses to about 65 nm for the high temperature ones. Structural properties were investigated using X-ray diffraction, Raman, and photoluminescence spectroscopy. Thermal stability was probed by differential scanning calorimetry coupled with thermogravimetry in Ar and air atmospheres. Chemical composition and purity of InN are strongly dependent on temperature and duration of the synthesis.