Preparation of Ultrafine β-Sialon Powder by Citrate Sol-Gel and Carbothermal Reduction Nitridation

Abstract

Ultrafine β-sialon powder is synthesized by citrate sol-gel and carbothermal reduction and nitridation (CRN) process. The presence of small amounts of β-sialon as crystal seed can obviously accelerate the formation of final β-sialon product and lower its formation temperature. The effects of nitriding temperature on the formation of the final β-sialon are investigated. The mean particle size of the prepared β-sialon powder is 100 ~ 150 nm. The β-sialon precursor gel and the ultrafine β-sialon powder are characterized by XRD, TG-DTA and SEM. The isoelectric point of ultrafine β-sialon is pH 2.46.

Synthesis of Hollow Sphere and 1D Structural Materials by Sol-Gel Process

“…In the past few decades, the sol-gel method (combined with other techniques including microwave heating, ultrasonication, spin-coating, dip coating, laminar flow coating, and strong field induction) have been used to prepare various kinds of advanced materials with different morphologies including magnetic [1,2,3,4,5,6,7,8,9,10], optical [11,12,13], electronic [14,15], and structural [16,17,18,19,20,21,22,23,24,25] particles, and hollow spheres [26], fibers [27], nanowires [28] and films [29,30,31,32,33,34]. Many reviews have been published on the preparation of particles and coatings using the sol-gel process; for instance, Guo et al [35] summarized the sol-gel synthesis and application of monodisperse nanoparticles and granules including Li 2 TiO 3 , ZnO-B 2 O 3 -SiO 2 additive, La 1−x Sr x CoO 3-δ (x = 0.1 − 0.7) and Y 3 Al 5 O 12 .…”