Lanthanum Oxyfluoride Sol−gel Thin Films by a Simple Single-Source Precursor Route

Abstract

Highly transparent and homogeneous nanostructured LaO 1-x F 1+2x (0e x e 1) thin films have been synthesized by a simple sol-gel procedure using La(hfa) 3 · diglyme (Hhfa ) 1,1,1,5,5,5-hexafluoro-2,4-pentanedione; diglyme ) bis(2-metoxyethyl) ether) as source compound for both lanthanum and fluorine. While thermal treatments up to 500°C resulted in highly fluorinated nanosystems, i.e., LaF 3 at 300°C and LaF 3 + LaOF at 500°C, pure and single-phase nanostructured lanthanum oxyfluoride thin films with a mean crystallite size of ∼15 nm have been obtained at 700°C. The microstructure and composition of the samples and their interplay with the synthesis procedure were investigated by glancing incidence X-ray diffraction, X-ray photoelectron, and X-ray excited Auger electron spectroscopy. Finally, the optical properties of the films were studied by UV-vis-NIR spectroscopy and spectroscopic ellipsometry.

High-Energy X-ray Photoemission and Structural Study of Ultrapure LaF3 Superionic Conductor Thin Films on Si

“…In this work, we studied the growth, morphology, and chemical composition of highly ordered LaF 3 epitaxial layers on silicon by high-energy X-ray photoelectron spectroscopy (HAXPES) flanked by conventional XPS, atomic force microscopy (AFM), and reflection high-energy electron diffraction (RHEED). Indeed, LaF 3 thin films have been investigated quite extensively in the literature. − ,,,− Different methods of growth were applied, including sol–gel technique, chemical vapor deposition, vacuum thermal deposition, and molecular beam epitaxy (MBE). Defects, either vacancies or impurities, play a fundamental role in ion conduction, but they also influence optical properties.…”

Synthesis, characterization and application of lanthanum-impregnated activated alumina for F removal

“…S6 †). The peaks of F 1s were resolved into 685.7 and 684.4 eV for Al-F and La-F, 35,36 respectively. Al-F was obtained in AA and LAA, whereas La-F was obtained in LAA and LaOOH.…”

Well-defined lanthanum ethylenediaminetetraacetates as the precursors of catalysts for the oxidative coupling of methane

“…Usually, the metal oxides can be synthesized in several ways, such as sol-gel [33][34][35][36], carbonate [37], templates [38][39][40], homogeneous precipitation [41,42] et al Thermal treatment of well-defined polymeric precursor method is attractive, since it decomposes to high purity oxides at a moderate calcinating temperature with explicit composition [43]. Besides that, there is template effect of precursor morphology during the syntheses of oxide through thermal decomposition method [44,45].…”