Oxide Nano Dispersion List
Nanoparticles have unique surface interface effect, small size effect, quantum size effect and macroscopic quantum tunneling effect, which have been widely used in the fields of light, electricity, magnetism, force, sound and catalysis. Nanoparticle dispersions can be prepared by uniformly dispersing nanoparticles in a liquid medium (such as water). Various forms of aggregates composed of dried nanoparticles can be reduced to primary particles and distributed stably and uniformly in the medium. Oxide nanoparticle dispersion refers to the dispersion of one or more oxide nanoparticles in another liquid medium.
Nano dispersions can be widely used in fields such as energy saving and heat insulation, electronic information, biomedical nanocomposites, and high-efficiency pseudo-homogeneous nano-catalysts.
- Nanocomposites: Nano-dispersions based on different functions can create a variety of functional nanocomposites such as light, electricity, and flame retardant. For example, zirconia has the advantages of high refractive index, good optical properties, low coefficient of thermal expansion, high hardness and excellent thermal stability. Transparent ZrO2 nanocomposites were prepared by solution blending method and when the inorganic filler is a transparent dispersion of nano-ZrO2, the nanocomposite film is still highly transparent when the amount of ZrO2 is very high. Similarly, the prepared resin transparent nanocomposites have good light emitting rate and have important application prospects in the field of LED lighting device packaging. In addition, various ultraviolet / infrared transparent nanocomposite films can be prepared by blending nano-dispersions with other solutions with shielded near-infrared nanoparticles. For example, because zinc oxide has excellent UV shielding and antibacterial properties, ZnO / carbon nanotubes / poly (butyl methacrylate) films can be prepared by in-situ polymerization, which not only has good light transmittance and UV shielding properties, but also has excellent mechanical properties (tensile strength and elongation at break).
Figure 1. SEM micrographs of PVA/ZrO2.
- Catalyst: Metal nanoparticles can be uniformly dispersed in a solvent to form a quasi-homogeneous system, which can be used to catalyze the reaction process. For example, the methanol and ethylene glycol phase dispersions of nano-ZnO can be used as pseudo-homogeneous nano-catalysts for alcoholysis of PET. The quasi-homogeneous nano-catalyst has the advantages of high efficiency and reusability, and has a good application prospect in the alcoholysis of PET. In addition, oxide nanodispersions can also be used in the field of photocatalysis. For example, ZrO2 can be used as a catalyst for photocatalytic degradation of organic pollutants in wastewater. Compared with common photocatalysts , ZrO2 has unique advantages because of its acid and alkali resistance and chemical inertia. The aqueous dispersion of nano-ZrO2 clusters can be prepared by introducing nano-ZrO2 aqueous phase dispersions into SrSnO3,.Because of its unique structure, the catalyst shows the advantages of high efficiency, easy recovery and reusability, and can be used for the degradation of many kinds of dye wastewater in the future.
Figure 2. Nano-dispersions used as photocatalyst.
There are many methods that can be used to prepare oxide nano-dispersions, such as liquid-solid-liquid phase transfer method, organometallic precursor thermal decomposition method, biomimetic and polymer template method, hydrothermal reaction method and sol-gel method.
- F.R.Lamastra.(2008) “Nanohybrid PVA/ZrO2 and PVA/Al2O3 electrospun mats.” Chemical Engineering Journal. 145(1): 169-175.
- Luzia Maria CastroHonori.(2020) “Supporting the photocatalysts on ZrO2: An effective way to enhance the photocatalytic activity of SrSnO3.” Applied Surface Science.528(30): 146991.