Combustion Based Synthesis of AlN Nanoparticles Using a Solid Nitrogen Promotion Reaction

Abstract

Combustion based synthesis of AlN nanoparticles using the "solid nitrogen" promotion reaction was investigated in Al 2 O 3 + 3Mg system in nitrogen atmosphere. A controlled amount of Mg + 0.5NH 4 Cl mixture as a solid source of nitrogen was blended with the Al 2 O 3 + 3Mg starting system and the synthesis reaction of AlN nanoparticles was conducted using the exothermic heat of the entire reaction system. The resulting AlN nanoparticles were characterized by X-ray diffraction (XRD), Raman and Fourier transform infrared spectroscopy (FTIR), PL spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and Brunauer-Emmett-Teller surface area techniques. The analysis results confirmed that single phase and crystalline AlN nanoparticles with an average size of 50-500 nm were obtained from the developed approach. Photoluminescence spectra of AlN nanopowders under the excitation of 230-270 nm UV light revealed that AlN emits yellow-red light having a wavelength near to 590 nm. The chemistry of the combustion process is discussed and the basic reactions that led to the formation of AlN are presented.

Morphological diversity of AlN nano- and microstructures: synthesis, growth orientations and theoretical modelling

“…The following chemical and physical methods have been used for synthesising AlN nanoparticles: carbothermal reduction-nitridation (CRN) [21][22][23][24][25][26][27][28][29][30][31][32], plasma synthesis (PS) [33][34][35][36][37][38][39][40], combustion synthesis (CS) [41][42][43][44], direct nitridation (DN) using NH 3 gas [45,46], and the pulsed wire discharge method (PWD) [47][48][49][50].…”

“…The reaction in plasma is a simple combination of Al and nitrogen molecules, as shown belowThe nitridation approaches used in the combustion synthesis (CS) of AlN NPs can be classified into two groups: magnesiothermic reduction-nitridation of Al 2 O 3 in the presence of halogen salts [41,42], and metathesis reaction between aluminium halide salts (Na 3 AlF 6 , AlF 3 , and AlCl 3 ) and alkali metal azides (NaN 3 and KN 3 ), referred to as ‘azide’ process [43,44]. The magnesiothermic reduction-nitridation [41,42] involves the preparation of Al 2 O 3 –Mg–NH 4 Cl precursor mixture and its subsequent combustion in a nitrogen atmosphere. During the combustion process, the temperature rapidly increases to 1400–1600°C range, and the reduction-nitridation of Al 2 O 3 occurs by the following equation:…”

Processamento, propriedades e aplicações das cerâmicas de nitreto de alumínio

“…A primeira linha de pesquisa é caracterizada pela otimização de l, similar ao observado nas décadas passadas, mas tendo como diferencial uma preocupação pelo comportamento mecânico. Mesmo com uma rota pré-estabelecida de processamento cerâmico, o AlN ainda tem estudos nas seguintes áreas: i) síntese de pós [123,124]; ii) processamento cerâmico em meio aquoso [125,126]; e iii) sistemas multicomponentes de aditivos de sinterização [38,57,94]. De modo geral, o processo de sinterização tem sido conduzido em forno convencional sem aplicação de pressão (pressureless sintering), forno convencional com aplicação de pressão (hot pressing sintering) e forno com aplicação de pressão e aquecimento induzido por corrente elétrica (spark plasma sintering).…”