Self-propagating high-temperature synthesis of (Ho1-xLax)2O3 nanopowders for magneto-optical ceramics

Abstract

Weakly agglomerated nanoparticles of (Ho 1-x La x ) 2 O 3 solid solutions were synthesized with the help of a self-propagating high-temperature synthesis (SHS). The nanopowders were studied by a simultaneous thermal analysis (TG-DSC), X-ray diffraction (XRD), BET and FT-IR spectroscopy methods. Changes of the particles morphology after annealing at different temperatures and ball milling were investigated by a scanning electron microscopy (SEM) and a dynamic light scattering (DLS) method. It was found that annealing at a temperature of 900 °C in air and ball milling of the SHS nanopowders allow obtaining rounded shape particles with a mean diameter of about 20 nm and C-type cubic crystal structure. Up to 10 mol.% of the lanthana was shown to dissolve in the holmium oxide nanoparticles.

Thermo-Optical Studies of Laser Ceramics

“…The prospects of using sesquioxide ceramics thanks to their thermo-optical properties arose the interest of researcher more than 50 years ago [ 55 ]. We pay great attention to manufacturing [ 46 , 56 , 57 , 58 , 59 , 60 ], as well as to studying [ 39 , 40 , 42 , 43 , 54 , 57 ] magneto-optical and thermo-optical properties of the sesquioxide ceramics Y 2 O 3 , Tb 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Er 2 O 3 , and Yb 2 O 3 , that will be considered in this section.…”

“…To date, many methods have been developed for both the synthesis of initial rare-earth oxide nanopowders and methods for their subsequent consolidation into optical-quality ceramics. In our works, we use the method of self-propagating high-temperature synthesis (SHS) to obtain nanopowders containing matrix elements uniformly distributed over the volume, sintering and auxiliary additives (LiF, ZrO 2 , and rare earth oxides other than the main matrix oxide) [ 58 , 60 ]. SHS consists in the synthesis of a precursor containing nitrates of the corresponding metals and organic fuel—acetic or aminoacetic acids, followed by thermal initiation of its combustion.…”

“…The sinterability of the individual oxides is usually insufficient for producing laser-quality ceramics without hot isostatic pressing and is a nontrivial task, even with its application. Therefore, at free vacuum sintering, a sintering additive La 2 O 3 [ 45 , 58 , 61 ] and in some cases Y 2 O 3 is used, when the solubility of lanthanum oxide is insufficient for a single-phase ceramics to be formed (for example, in Dy 2 O 3 [ 42 , 56 ]). These additives are isovalent to REE oxides and, except for some decrease in thermal conductivity, have do not negatively affect the characteristics of ceramics.…”

Fabrication, microstructure and optical characterizations of holmium oxide (Ho2O3) transparent ceramics

“…There have been some reports on the preparation of Tb 2 O 3 [33,34], Dy 2 O 3 [35][36][37], Ho 2 O 3 [38][39][40][41][42] and Er 2 O 3 [43] magneto-optical transparent ceramics. Ho 2 O 3 ceramics were first reported in 2002 [44].…”

Спектроскопия Иттриевого Скандата, Легированного Ионами Тулия

“…Такие свойства особенно ценятся при создании твердотельных лазеров [3][4][5][6][7], поэтому Y 2 O 3 и Sc 2 O 3 , легированные редкоземельными ионами, могут стать достойной альтернативой кристаллам ИАГ. Оксидные материалы считаются перспективными для различных применений, среди которых: твердотельные светоизлучательные устройства [8,9], высокоэффективные люминесцентные материалы [10,11], редкоземельные магниты [12,13], материалы для магнитооптической записи [14] и т. д.…”