Selective and Controlled Synthesis of Single-Crystalline Yttrium Hydroxide/Oxide Nanosheets and Nanotubes

Single-crystalline yttrium hydroxide nanotubes could be successfully synthesized in large quantities via a metastable nanosheet precursor reacted with sodium hydroxide under hydrothermal conditions. The nanosheet precursors were obtained through a facile hydrothermal synthetic method using soluble yttrium nitrate as the yttrium source and triethylamine as both an alkaline and complexing reagent. The influences of reaction time and concentration of sodium hydroxide on the formation of yttrium hydroxide nanotubes were investigated. Yttrium oxide and europium-doped yttrium oxide nanosheets and nanotubes could also be selectively obtained via a thermal decomposition method using the corresponding hydroxides as precursor. The phase structures, morphologies, and properties of the as-prepared products were investigated in detail by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), selected area electron diffraction (SAED), high-resolution transmission electron microscopy (HRTEM), and photoluminescence spectroscopies. The formation mechanisms of yttrium hydroxide nanotubes were discussed based on the experimental results. These low-dimensional nanostructures could be expected to bring new opportunities in the vast research and application areas.