Metastable states of laser synthesized oxide nanoparticles

Sintering of transparent Yb-doped Lu 2 O 3 ceramics using nanopowder produced by laser ablation method

“…Same features were observed for Eu:Lu 2 O 3 films prepared by pulsed laser deposition and were attributed to the monoclinic phase [23]. This conclusion is confirmed by analogy with the behavior of Y 2 O 3 nanoparticles synthesized by laser ablation method [24]. From XRD analysis, we determined the lattice constants of the main monoclinic phase via Rietveld refinement: a = 13.72 Å, b = 3.42 Å, c = 8.45 Å, b = 100.27°.…”

Sintering and optical quality of highly transparent yb‐doped yttrium lanthanum oxide ceramics

“…2. It revealed all the samples are monoclinic single-phase, which typical for Y 2 O 3 produced by laser synthesis [13]. The phase characteristics for MI-151 nanopowder: a = 13.96 Å, b = 3.516 Å, с = 8.65 Å, β = 100.2°, coherence area (crystallite size) 18 nm.…”

“…TG-DSC analysis of the nanopowder (Fig. 3) revealed weak exothermal reaction of phase transformation (from monoclinic to cubic) at 1150-1250 °С, which is typical for metastable yttria oxide nanoparticles [13]. The content of adsorbats in the powder was 6 wt.%.…”

Highly transparent Yb-doped (LaxY1−x)2O3 ceramics prepared through colloidal methods of nanoparticles compaction

“…The analysis revealed the particles to be monoclinic B-type Y 2 O 3 (Base-centered monoclinic, S.G: C2/m, PDF No. 047-1274), which is typical for Y 2 O 3 condensed from a vapor phase [25,40]. The phase characteristics for Yb 0.17 La 0.19 Y 1.64 O 3 nanopowder are: a = 13.96 Å, b = 3.516 Å, c = 8.65 Å, ␤ = 100.2 • , coherence area (crystallite size) 18 nm.…”

“…A characteristic feature of the laser synthesized nanoparticles is a metastable phase structure, which is caused by extremely fast cooling, when the laser plasma intermingles with air [25]. This monoclinic Y 2 O 3 lattice transforms to cubic, when the particles are heated [26].…”