Nanoscopic yttrium oxide fluorides: non-aqueous fluorolytic sol–gel synthesis and structural insights by 19F and 89Y MAS NMR

Abstract

Nanoscopic yttrium acetate fluorides Y(CH₃COO)_3−zF_z and yttrium oxide fluorides YO_(3−z)/2F_z were prepared with tunable Y/F molar ratios via the fluorolytic sol–gel route. All samples were characterized by X-ray diffraction, elemental analysis and thermal analysis. In addition, local structures of all samples were studied by ¹⁹F MAS, ¹⁹F–⁸⁹Y CP MAS and ¹H–⁸⁹Y CP MAS NMR spectroscopy and the respective chemical shifts are given. For both classes of compounds, only the fluorination using one equivalent of F (z = 1) leads to defined, well crystalline matrices: yttrium acetate fluoride Y(CH₃COO)₂F and r-YOF.