The Effects of Various Parameters of the Microwave-Assisted Solvothermal Synthesis on the Specific Surface Area and Catalytic Performance of MgF2 Nanoparticles

Yawen Wang (1) , Zahra Gohari-Bajestani (2) , Jérôme Lhoste (2) , Sandy Auguste (2) , Annie Hémon-Ribaud (2) , Monique Body (2) , Christophe Legein (2) , Vincent Maisonneuve (2) , Amandine Guiet (2) , Sylvette Brunet (1)

1 IC2MP [Poitiers] - Institut de chimie des milieux et matériaux de Poitiers [UMR 7285]
2 IMMM - Institut des Molécules et Matériaux du Mans

High-specific-surface-area MgF2 was prepared by microwave-assisted solvothermal synthesis. The influences of the solvent and the magnesium precursors, and the calcination atmospheres, on the nanoparticle sizes and specific surface areas, estimated by X-Ray Powder Diffraction, N2 sorption and TEM analyses, were investigated. Nanocrystallized (~7 nm) magnesium partially hydroxylated fluorides (MgF2−x(OH)x) with significant specific surface areas between 290 and 330 m2∙g−1 were obtained. After activation under gaseous HF, MgF2−x(OH)x catalysts underwent a large decrease of both their surface area and their hydroxide, rates as shown by their 19F and 1H solid-state NMR spectra. Expect for MgF2 prepared from the acetate precursor, an activity of 30–32 mmol/h∙g was obtained which was about 40% higher compared with that of MgF2 prepared using Trifluoroacetate method (21.6 mmol/h∙g).

Mots clés: inorganic fluorides; nanoparticles; nanoparticle size; microwave synthesis; solvothermal route; catalytic performance; BET surface area; XRPD data; TEM data; solid-state NMR

Domaines: Matériaux; Chimie inorganique; Cristallographie

Yawen Wang, Zahra Gohari-Bajestani, Jérôme Lhoste, Sandy Auguste, Annie Hémon-Ribaud, et al.. The Effects of Various Parameters of the Microwave-Assisted Solvothermal Synthesis on the Specific Surface Area and Catalytic Performance of MgF2 Nanoparticles. Materials, 2020, 13 (16), pp.3566. ⟨10.3390/ma13163566⟩. ⟨hal-02961375⟩