摘要:
Embodiments of a method for synthesizing aqueous precursors comprising Hf4+ or Zr4+ cations, peroxide, and a monoprotic acid are disclosed. The aqueous precursors are suitable for making HfO2 and ZrO2 thin films, which subsequently can be patterned. The disclosed thin films are dense and continuous, with a surface roughness of = 0.5 nm and a refractive index of 1.85-2.0 at ? = 550 nm. Some embodiments of the disclosed thin films have a leakage-current density = 20 nA/cm2 at 1 MV/cm, with a dielectric breakdown = 3 MV/cm. The thin films can be patterned with radiation to form dense lines and space patterns.
摘要:
Embodiments of a method for synthesizing aqueous precursors comprising Hf4+ or Zr4+ cations, peroxide, and a monoprotic acid are disclosed. The aqueous precursors are suitable for making HfO2 and ZrO2 thin films, which subsequently can be patterned. The disclosed thin films are dense and continuous, with a surface roughness of = 0.5 nm and a refractive index of 1.85-2.0 at ? = 550 nm. Some embodiments of the disclosed thin films have a leakage-current density = 20 nA/cm2 at 1 MV/cm, with a dielectric breakdown = 3 MV/cm. The thin films can be patterned with radiation to form dense lines and space patterns.
摘要:
Preparation of semiconductor nanocrystals and their dispersions in solvents and other media is described. The nanocrystals described herein have small (1 -10 nm) particle size with minimal aggregation and can be synthesized with high yield. The capping agents on the as-synthesized nanocrystals as well as nanocrystals which have undergone cap exchange reactions result in the formation of stable suspensions in polar and nonpolar solvents which may then result in the formation of high quality nanocomposite films.
摘要:
Surface-modified zirconia nanoparticles include zirconia nanoparticles and surface-modifying ligands attached to the zirconia nanoparticles. The ligand includes a hydroxamate functionality, and either a reactive group or an oligomeric group. Reactive groups include chain transfer groups or photoinitiator groups. Oligomeric groups include poly(meth)acrylate or poly(meth)acrylamide groups. Articles can be prepared that include the surface-modified zirconia nanoparticles in an organic matrix.
摘要:
Porous materials are fabricated using interpenetrating inorganic-organic composite gels. A mixture or precursor solution including an inorganic gel precursor, an organic polymer gel precursor, and a solvent is treated to form an inorganic wet gel including the organic polymer gel precursor and the solvent. The inorganic wet gel is then treated to form a composite wet gel including an organic polymer network in the body of the inorganic wet gel, producing an interpenetrating inorganic-organic composite gel. The composite wet gel is dried to form a composite material including the organic polymer network and an inorganic network component. The composite material can be treated further to form a porous composite material, a porous polymer or polymer composite, a porous metal oxide, and other porous materials.
摘要:
Porous materials are fabricated using interpenetrating inorganic-organic composite gels. A mixture or precursor solution including an inorganic gel precursor, an organic polymer gel precursor, and a solvent is treated to form an inorganic wet gel including the organic polymer gel precursor and the solvent. The inorganic wet gel is then treated to form a composite wet gel including an organic polymer network in the body of the inorganic wet gel, producing an interpenetrating inorganic-organic composite gel. The composite wet gel is dried to form a composite material including the organic polymer network and an inorganic network component. The composite material can be treated further to form a porous composite material, a porous polymer or polymer composite, a porous metal oxide, and other porous materials.
摘要:
La composition de l'invention est à base d'oxydes de zirconium, de cérium et d'au moins une terre rare autre que le céhum, avec une teneur en oxyde de cérium d'au plus 50% en masse et elle présente après calcination à 1000°C, 6 heures, une température maximale de réductibilité d'au plus 500°C et une surface spécifique d'au moins 45 m 2 /g. Elle est préparée par un procédé dans lequel on fait réagir en continu un mélange de composés du zirconium, du cérium et de l'autre terre rare avec un composé basique avec un temps de séjour d'au plus 100 millisecondes; le précipité est chauffé puis mis en contact avec un tensioactif avant d'être calciné.