| dc.description.abstract | Magnetic nanomaterials have received significant attention because of their remarkable
properties enabling applications in various fields such as catalysis, as contrast agents for
magnetic resonance imaging, in sensing applications, as environmental catalysts and as
adsorbents. Magnetic properties of materials depend on certain factors such as size, shape,
crystallinity, composition, crystal structure, and synthetic methodology. Most of the pristine
magnetic nanoparticles are highly pyrophoric in nature which poses difficulties in handling
these materials. In addition, the ease of oxidation and potential toxicity of these materials
preclude their practical applications. Further, these magnetic nanoparticles have strong
magnetic interactions between them which leads to the aggregation of particles. These
features affect the magnetic behaviour as well as the other characteristics of the material. In
this context, fabricating magnetic nanomaterials with desired magnetic properties, chemical
stability and surface chemistry is quite challenging. Similarly, plasmonic metal nanoparticles
such as Ag and Cu also suffer from issues pertaining to oxidative instability upon air
exposure under ambient conditions. Therefore, it is crucial to develop protection strategies to
stabilize nanoparticles surface against oxidation.
This thesis describes the synthesis of carbon encapsulated mono- and bi-metallic
nanoparticles using solvated metal atom dispersion method in conjunction with digestive
ripening approach followed by thermal annealing. The aim of the work is to understand the
effect of size, shape, composition, and the nature of surface on the properties of these
metallic nanomaterials. In this direction, nanosystems of Fe, Ag, Cu, Fe3C, and FeCo have
been studied. | en_US |
