文献类型：期刊文献

英文题名：Synthesis and characterization of nano Si3N4 powder via sol foaming and carbothermal reduction and nitridation

作者：Li, Sifang[1];Wang, Yan[1];Wang, Deqiang[1];Fan, Yalei[2]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai 200237, Peoples R China;[2]Hebei Univ Architecture, Sch Mech Engn, Zhangjiakou 075132, Peoples R China

年份：2024

卷号：130

期号：10

外文期刊名：APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING

收录：;EI(收录号：20243717016316);WOS:【SCI-EXPANDED(收录号:WOS:001307857600003)】；

语种：英文

外文关键词：Nanoparticles; Silicon compounds; Sol-gel processing; Nitridation; Reduction

摘要：Nano Si(3)N(4 )powder was successfully synthesized using a combination of sol foaming and carbothermal reduction and nitridation techniques. The process utilized fumed silica (amorphous nano SiO2 powder) as the silicon source, sucrose (C12H22O11) as the carbon source, ammonium chloride (NH4Cl) as the foaming agent, and nitric acid (HNO3) as the oxidant, to prepare precursor of the Si3N4 powder. The objective of this research was to investigate the influence of various factors on the size of the Si3N4 particles. Specifically, the molar ratio of NH4Cl to SiO2 (epsilon), the foaming temperature, the sintering temperature, and the holding time were analyzed in detail. The results revealed that under the optimized conditions of epsilon = 1, a SiO2 : C12H22O11 = 1 : 1.5, and a foaming temperature of 350 degrees C, a fluffy precursor was obtained. This precursor featured amorphous SiO(2 )evenly coated with organic carbon, which was crucial for the subsequent synthesis process. Subsequently, the precursor was subjected to a nitridation process at 1500 degrees C for 2 h. This resulted in the formation of nano alpha-Si3N4 powder. The powder displayed a specific surface area of about 52 m(2)/g, an average particle size of approximately 20 nm, and a high degree of sphericity.