Synthesis of one-dimensional ZrO₂ nanomaterials from Zr(OH)₄ precursors assisted by glycols through a facile precursor-templating method

Abstract

One-dimensional (1D) ZrO2 nanomaterials were successfully prepared from local zircon-based Zr(OH)4 precursors assisted by glycols (as the 1D structure directing templates) in water-based solvent through a facile precursor-templating method. The 1D ZrO2 nanomaterials were initially synthesized by mixing the precursors with glycols at precursor pHs 9, 7, 5, 4, 3, 2, and 1. Glycols were mixed with the precursors at a stoichiometric mole ratio of 1:1 at precursor pHs 9, 7, and 5. Meanwhile, the addition of glycols to the precursor at pH 1–4 was carried out based on a precursor-to-glycol volume ratio (Vp/Veg) of 1, 2.5, and 15. At 800 °C, the samples synthesized at precursor pHs 9, 7, 5, 4 and 3, generally consisted of metastable tetragonal and monoclinic phases of ZrO2. The samples synthesized at precursor pHs 3 and 4 exhibited 1D structures such as nanorods, nanotubes, and elongated agglomerates at that temperature. Besides that, 1D ZrO2 nanomaterials with high specific surface areas were produced, namely 48.305 m2 g−1 and 47.283 m2 g−1, at precursor pH 3 with Vp/Veg = 15 and at precursor pH 4 with Vp/Veg = 2.5, respectively. During the synthesis of the nanomaterials, a lower precursor pH, especially from pH 3–4, was observed to be an optimum condition for the formation of the 1D ZrO2 structure. Meanwhile, at precursor pH 3, the higher the precursor concentration used in the synthesis, the better the characteristics of zirconia produced, such as more uniform 1D structures, longer nanorods or nanotubes, and the highest specific surface areas compared to the other samples.