Stabilization of Tetragonal Zirconia Nanocrystallites Using an Original Supercritical-Based Synthesis Route

Autor: Matthew R. Suchomel, Gilles Philippot, Aimery Auxéméry, Cyril Aymonier, Denis Testemale
Přispěvatelé: Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Matériaux, Rayonnements, Structure (MRS), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), The authors acknowledge the support of the Innovation Fund Denmark (GCAM), the Centre National de la Recherche Scientifique (CNRS), and the Région Nouvelle Aquitaine. The authors also acknowledge the European Synchrotron Radiation Facility for provision of synchrotron radiation beamtime and facilities, the FAME team for assistance in using their beamline, and the Diamond Light Source for mail-in PDF measurement access at Beamline I15-1 under Proposal CY22774.
Rok vydání: 2020
Předmět:
Zdroj: Chemistry of Materials
Chemistry of Materials, American Chemical Society, 2020, 32 (19), pp.8169-8181. ⟨10.1021/acs.chemmater.0c01550⟩
ISSN: 1520-5002
0897-4756
DOI: 10.1021/acs.chemmater.0c01550
Popis: International audience; To understand the importance of the particle size on the stabilization of metastable tetragonal ZrO2, ultrafine ZrO2 nanocrystals were synthesized via (i) the precipitation method in supercritical water using nitrate precursors, (ii) the sol–gel method in a supercritical ethanol–water mixture, and (iii) the borderline nonhydrolytic sol–gel route in supercritical ethanol using propoxide precursors. The obtained nanocrystals displayed a variation of the monoclinic versus tetragonal molar fractions from 100 wt % down to ≈10 wt % of monoclinic phase. This variation was concomitant with an overall size decrease of the nanocrystals, ranging from 7 to 2 nm depending on the synthesis procedures. Phase contents were quantified by refinement analysis of X-ray scattering data sets and crosschecked with Raman spectroscopy. Our results suggest that an upper limit of ≈90 wt % of the tetragonal ZrO2 phase is possible, even for ultrafine nanoparticles (2 nm). These findings thus question the existence of any critical size limit below which stabilization of pure t-ZrO2 is attainable at low temperatures.
Databáze: OpenAIRE