In this study, we demonstrate a synthetic method of zirconia sol using ZrO(NO₃)₂·xH₂O as Zr⁴⁺ precursor, tetramethylammonium hydroxide as mineralizer, and oxalic acid as a complexing agent. X-ray diffraction, transmission electron microscopy, Raman spectroscopy, and UV–vis adsorption spectroscopy were used to characterize the nanocrystals. The effect of oxalic acid content on the growth of zirconia nanocrystals was investigated. Zirconia sol cannot be synthesized without oxalic acid. The oxalic acid content has no obvious effect on the phase formation of monoclinic zirconia. The transparent and monoclinic zirconia sol with particle size <10 nm was synthesized. This provides a new hydrothermal system for the synthesis of zirconia sol.

中文翻译：

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单斜氧化锆溶胶的水热合成

_{在本研究中，我们展示了一种使用 ZrO(NO 3} ) ₂ · x H ₂ O 作为 Zr ⁴⁺的氧化锆溶胶的合成方法前驱体，四甲基氢氧化铵为矿化剂，草酸为络合剂。X 射线衍射、透射电子显微镜、拉曼光谱和紫外-可见吸收光谱用于表征纳米晶体。研究了草酸含量对氧化锆纳米晶体生长的影响。没有草酸就不能合成氧化锆溶胶。草酸含量对单斜氧化锆的相形成没有明显影响。合成了粒径<10nm的透明单斜氧化锆溶胶。这为氧化锆溶胶的合成提供了一种新的水热体系。