Investigation of the interaction between adsorbed water and various morphologies of boehmite nanoparticles prepared by continuous supercritical hydrothermal synthesis

Erwan Peigney (1) , Angeline Poulon-Quintin (1) , Marjorie Cavarroc (2) , Guillaume Aubert (1) , Mathieu Duttine (1) , Christine Labrugère Sarroste (3) , Cyril Aymonier (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Safran Tech
3 PLACAMAT - Plateforme Aquitaine de Caractérisation des Matériaux

Boehmite applications are often subject to specific characteristics in terms of morphologies and surface properties. The versatile continuous supercritical hydrothermal method allows synthesizing various boehmite morphologies from rhombic to hexagonal platelet-like nanoparticles depending on the preferential adsorption of part of the precursor after transformation species on the (020) surface resulting in a preferential growth along [001] and mostly [100] directions. This adsorption on surface free sites plays the role of morphology stabilizer and results in the reduction of adsorbed water. The interaction between adsorbed water and the boehmite morphology depends on various parameters: 1) the structure order of boehmite as exhibited by XPS analysis associated with 1H Solid-State NMR spectroscopy and, 2) the number of available free sites, which tend to be filled by the adsorption of nitrates as observed by Raman spectroscopy.

Mots clés: Synthetic boehmite nanoparticles; Water and nitrate adsorption; pH-dependent morphology; Continuous supercritical hydrothermal synthesis; Supercritical water

Domaines: Matériaux

Erwan Peigney, Angeline Poulon-Quintin, Marjorie Cavarroc, Guillaume Aubert, Mathieu Duttine, et al.. Investigation of the interaction between adsorbed water and various morphologies of boehmite nanoparticles prepared by continuous supercritical hydrothermal synthesis. Journal of Supercritical Fluids, 2023, 193, 105829 (11 p.). ⟨10.1016/j.supflu.2022.105829⟩. ⟨hal-03907821⟩