Chemistry Reference
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using different methods and techniques [51, 52]. The group
developed a hydrothermal synthetic strategy based on liquid-
solid-solution growth, which was employed to synthesize a range
of REF
nanomaterials. Figure 2.4 shows the TEM images of the
hexagonal- or orthorhombic-phase polyhedron of fluorides. Alkali-
lioleate, linoleate acid, and ethanol were used with rare earth
nitrate precursors at a reaction temperature of 100-200°C. The
resulting nanocrystals were varied in shape and size but generally
monodisperse and crystalline. The authors also investigated the
dependence of nanocrystal shapes on the rare earth ionic radius
and proposed that the growth of nanocrystals changed with ionic
size.
4
Figure 2.4
TEM images of (A, B, C) NaYF4, (D) CeF3, (E) PrF4, (F) NdF3,
(G,H) LaF3, (I) NaYb2F7 [52].
Using a microemulsion method, Lemyre and Ritcey [53]
demonstrated the synthesis of a range of 0D fluorides nanomaterials.
YCl
were used as precursors and dissolved in
the microemulsion of water, Igepal CO520, and cyclohexane.
The resultant 0D nanoparticles showed high crystallinity,
monodispersity, and different morphologies (Fig. 2.5). Surfactant-
to-water ratio and precursor concentrations played a critical role in
shape and size control of these materials. Similar 0D spherical Y
and NH
HF
3
4
2
O
2
3
has been reported by Arriagada
et al
. [54] using a microemulsion
method.
