Peculiarities of γ-Al[sub.2]O[sub.3] Crystallization on the Surface of h-BN Particles

• Published in: Materials 2022-11, Vol.15 (22)
• Main Authors: Grigoriev, Sergey N, Trusova, Elena A, Afzal, Asya M, Soe, Thet Naing, Kurmysheva, Alexandra Yu, Kuznetsova, Ekaterina, Smirnov, Anton, Solís Pinargote, Nestor Washington
• Format: Article
• Language: English
• Subjects: Boron nitride; Crystals; Electric properties; Electrical conductivity; Powders; Raw materials; Structure
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma15228054

The main goal of the present work was to synthesize a composite consisting of h-BN particles coated with a γ-Al[sub.2]O[sub.3] nanolayer. A method was proposed for applying nanocrystalline γ-Al[sub.2]O[sub.3] to h-BN particles using a sol-gel technique, which ensures the chemical homogeneity of the composite at the nano level. It has been determined that during crystallization on the h-BN surface, the proportion of spinel in alumina decreases from 40 wt.% in pure γ-Al[sub.2]O[sub.3] to 30 wt.% as a result of the involvement of the B[sup.3+] ions from the surface nitride monolayers into the transition complex. For comparison, nano-alumina was synthesized from the same sol under the same conditions as the composite. The characterization of the obtained nanostructured powders was carried out using TEM and XRD. A mechanism is proposed for the formation of a nanostructured γ-Al[sub.2]O[sub.3]@h-BN composite during the interaction of Al-containing sol and h-BN suspension in aqueous organic media. The resulting composite is a promising model of powdered raw materials for the development of fine-grained ceramic materials for a wide range of applications.