Home» CeO2 Nanoparticles Dispersion
Nanomaterials are being applied across a wide range of high-tech industries and advanced technologies due to their excellent optical, magnetic, catalytic and electronic properties. The properties of nanomaterials depend greatly on their structure, shape, and size.
Cerium is a Block F, Period 6 element. It is the most abundant of the rare earth elements, and is found in minerals bastnasite, synchysite, hydroxylbastnasite, sallanite, monazite, rhabdophane, and zircon. It is malleable and oxidizes very readily at room temperature.
CeO2 Nanoparticles Dispersion: Cerium (IV) oxide, also known as ceric oxide, ceric dioxide, ceria, cerium oxide or cerium dioxide, is an oxide of the rare-earth metal cerium. It is a pale yellow-white powder with the chemical formula CeO2. It is an important commercial product and an intermediate in the purification of the element from the ores. The distinctive property of this material is its reversible conversion to a non stoichiometric oxide.
Ceria (cerium oxide, CeO2) nano dispersion finds applications in the precision polishing of most semiconductor substrate materials including silicon, sapphire, GaAs, etc. Ceria dispersion has been shown to not only demonstrate tremendous advantages in the planarization process of most semiconductor materials but glassy materials employed in photonic applications as well.
CeO2 Nanoparticles Dispersion
Today, cerium oxide is largely used in the catalysis field (mainly for diesel engines), and in chemical and mechanical polishing (CMP). However, cerium oxide is also well known for its optical properties and ability to filter ultraviolet (UV) rays. Moreover, expertise ensures good size control from 5-nm diameter up to 100 nanometers. Researchers are able to obtain stable sols of cerium oxide nanoparticles with diameters of 10 nm. These sols appear as a clear liquid, since the particles are small enough to be totally transparent. For instance, at the same solid concentration (1g/l) and for similar particle size, a titanium dioxide sol appears milky.
Water-repellence and water-barrier properties are of primary importance for the durability and the stability of the coatings. The action of rain and humidity on outdoor constructions is a key factor in the degradation of the coatings because photo-degradation and final failure of the protective coating is the result of the combined action of UV, oxygen and water molecules. Moreover, water penetration in the coating leads to a lack of adherence of the coating onto the wood substrate, causing macroscopic failure. In this respect, a water absorption test on pine panels was performed, comparing a reference to a cerium oxide colloid modified alkyd formulation. The water absorption of the reference is 72 g/m2 and decreased to 45 g/m2 for the cerium oxide containing coating.
Cerium oxide nanoparticles, properly dispersed in coating formulations using the specific chemistry described previously, combine the advantages of organic ultraviolet (UV) absorbers with those of mineral additives. The cerium oxide nanoparticles ensure the durability of the UV absorption function whilst improving the hardness and strengthening the organic binders currently used in wood technology. Since the nanoparticles do not scatter light, the coating remains transparent. The transparency (i.e. no coloration, no whitening) is an important requirement for the wood coating industry; since wood is a natural material, the coating must be as neutral as possible. When the durability is targeted, colored pigments are often added to help in this way, but this negatively impacts the aesthetics of the end product. Organic UV absorbers are also efficient, but their actions are limited because of progressive destruction of active molecules (migration, leaching, photochemical activity).
Cerium Nanomaterials have unique regenerative properties owing to their low reduction potential and the coexistence of both Ce(3+)/Ce(4+) on their surfaces. Defects in the crystal lattice due to the presence of Ce(3+) play an important role in tuning the redox activity of Cerium nanomaterials. The surface Ce(3+):Ce(4+) ratio is influenced by the microenvironment. Therefore, the microenvironment and synthesis method adopted also plays an important role in determining the biological activity and toxicity of Cerium nanodispersions. The presence of a mixed valance state plays an important role in scavenging reactive oxygen and nitrogen species. They found to be effective against pathologies associated with chronic oxidative stress and inflammation. Also they are well tolerated in both in vitro and in vivo biological models, which make cerium nano dispersions well suited for applications in nanobiology and regenerative medicine.