Page 29 - Synthesis of Functional Nanoparticles Using an Atmospheric Pressure Microplasma Process - LiangLiang Lin
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Introduction - Plasma and Microplasma-assisted Nanofabrication
cells by hyperthermia.
In addition to the hyperthermia, magnetic nanoparticles can be also used for drug delivery. By engineering drugs with magnetic properties and put in a controllable external magnetic field, they can be transported and fixed at the local site where the medication should be released. Meanwhile, drug delivery to a specific site can also eliminate possible side effects and reduce the dosage required. The surfaces of these composites are generally modified by organic polymers or inorganic metals to make them biocompatible.80,81 The drug localization process uses magnetic delivery systems which is based on the competition forces between the the blood compartment and the magnetic forces from the extelnal magnetic field.
4) Functional coatings
Another promising field for nanoparticles lies in the deposition of functional coatings. Metal oxide nanomaterials with different performances are perfect coating materials in many applications. For example, TiO2 coated surface is hydrophilic and remain transparent under mist or rainwater because the contact angle between water and surface is small. There is hardly any water droplet formed on the coated surface. Such coatings could be used for eyeglasses or automobile side-view mirrors.137 Al2O3 nanomaterial is an ideal coating material which is very attractive for the metal cutting industry because of its favorable chemical stability, excellent thermal property, great wear and deformation resistance, together with its super toughness.138 Cu2O nanomaterials recently have received significant attentions as alternatives for indium tin oxide (ITO) in transparent conductive films, which are attributed to their excellent optical absorption properties.139 Mo oxides coatings have also been used in a wide range of engineering fields due to their high melting point, excellent corrosion resistance as well as beneficial mechanical property, making it possible to control the friction and wear performance of materials over a broad range of temperatures.140
In addition to metal oxide nanomaterials, metal nitrides, especially transition metal nitrides, have attracted enormous interest due to their extraordinary properties. They are known for the refractory properties, meaning chemically stable at temperatures above 2000 °C while still exhibit metallic behavior. Thus, they can be used as ideal coating material of high performance such as plasmonics, cermet, cutting tools, and refractory material. Such coatings as cubic boron nitride (c-BN) nanofilms, being similar to diamond in structure, are extremely stable under high pressure and temperature.138 Incorporating a transition metal, for instance, Ti, into the BN composites introduces metallic bonding. As a result, it not only increases the adhesion between the coating and the substrate, but also enhances the wear properties. The generated Ti-B-N nitrides films would perform well as radiation hard semiconductors, or as efficient heat-dissipating semiconductor substrates.

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