A study on boron nitride nanomaterials And their nanocomposites for Electrical magnetic and Surface properties

Abstract

Boron Nitride (BN) is a ceramic material capable of withstanding newlinevery high temperatures and has a very high bandgap. It is a polymorphic newlinecompound made of boron and nitrogen. It exists in several different crystal newlinestructures namely amorphous BN, hexagonal BN (hBN) and cubic BN among newlineothers. Here the research work focuses on the varied applications in which newlineBN plays a major role. Boron Nitride Nanotubes (BNNTs) are the center of newlineattention in this research work. BNNTs are rolled-up variations of hBN. They newlineare highly crystalline akin to carbon nanotubes (CNTs) but offer better newlinethermal conductivity than CNTs. They are used in medical applications, newlinenanocomposites and neutron shields to name a few. They can be dispersed newlineeasily in a polymer matrix than CNTs, this property is quite rare in newlinenanomaterials. Here, hBN in both particulate form and nanotube form were newlineused to fabricate nanocomposites. newlineThis research thesis is divided into three sections, each section newlinecontaining separate works using BN nanomaterials. newline1. BNNT synthesis and ferromagnetism in BNNTs newlineBNNTs were synthesized by chemical vapor deposition technique newline(CVD) at 1150 °C. The CVD technique is very simple and it offers high yield newlineand high purity compared to other techniques such as laser ablation and arc newlinedischarge. Elemental amorphous boron and nickel oxide were the two solid newlineprecursors used. The synthesis was carried out in a tubular furnace, with the newlinereactants carefully mixed in weight ratios and placed inside newline