Sol-gel synthesis and characterization of B4C nanopowder

Abstract

In this research, the B4C nanopowder was synthesized through sol-gel method. Nanometric size of precursors were controlled through dispersing agents and controlling pH inside the sol. Mixing the ingredients in molecular size was one of the important reasons in decreasing synthesis temperature of boron carbide particles. In order to evaluate product formation mechanism during sol-gel process, TEM, SEM, DTA/TG, BET, XPS, FTIR and DLS analysis methods were employed. DLS analysis revealed that precursor's particles inside the Sol were below 10 nm. FTIR analysis on chemical bonds indicated that the B-O-C bond was formed inside the gel powder. DTA analysis demonstrated that B4 C powder particles were formed at the temperature around 1270 °C. Superficial investigations illustrated that the specific surface area of the synthesized B4 C particles is equivalent to 154 m2/g, and also the surfaces of these particles were porous. Further, the size of these cavities is in the meso range. Structural images showed that particles were less than 30 nm. These particles morphology were depend on storage time at the heating stage, as with increasing synthesis time the growth mechanism changes while spherical form of particle shapes converts to whisker.