The synthesis of NaYF₄ compounds via the “soft chemistry” of sulfide precursors (a simple Y₂S₃ and a complex NaYS₂) was performed. Hydrofluoric acid solution (HF) at a concentration of 3–45% and different contents of a saturated aqueous solution of sodium fluoride that was acidified by hydrofluoric acid (NaF + HF) were used as fluorinating components. When the fluorination proceeded using different concentrations of hydrofluoric acid, yttrium fluoride (YF₃) formed. NaYF₄ was obtained via different synthesis conditions as a mixture of cubic and hexagonal phases in nanoparticle dimensions (α=30–100 nm, β=28–60 nm).

中文翻译：

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由硫化物前体合成NaYF ₄化合物

通过硫化物前体（简单的Y ₂ S ₃和复杂的NaYS ₂）的“软化学”合成NaYF ₄化合物。使用浓度为3–45％的氢氟酸溶液（HF）和由氢氟酸（NaF + HF）酸化的氟化钠饱和水溶液的不同含量作为氟化组分。当使用不同浓度的氢氟酸进行氟化时，形成氟化钇（YF ₃）。NaYF ₄通过不同的合成条件以纳米和立方尺寸（α= 30–100 nm，β= 28–60 nm）的立方相和六方相的混合物形式获得。