A process of making a dense, cohesive and uniform aluminum oxide coating on a metallic substrate includes electrodepositing polynuclear aluminum oxide hydroxide clusters from a polynuclear aluminum oxide hydroxide cluster solution on a metallic substrate to form a precursor coating, and post-treating the precursor coating to form a final aluminum oxide coating on the metallic substrate.

A process of making a dense, cohesive and uniform aluminum oxide coating on a metallic substrate includes electrodepositing polynuclear aluminum oxide hydroxide clusters from a polynuclear aluminum oxide hydroxide cluster solution on a metallic substrate to form a precursor coating, and post-treating the precursor coating to form a final aluminum oxide coating on the metallic substrate.

Disclosed is boehmite having a ratio of a micropore volume to a mesopore volume of 0.50 or more and a loose bulk density of 0.30 g/mL or more. The loose bulk density is preferably 0.70 g/mL or more.

Disclosed is boehmite having a ratio of a micropore volume to a mesopore volume of 0.50 or more and a loose bulk density of 0.30 g/mL or more. The loose bulk density is preferably 0.70 g/mL or more.

A negative electrode active material for a non-aqueous electrolyte secondary battery, includes: negative electrode active material particles that contain a silicon compound (SiO.sub.x: 0.5?x?1.6) containing a Li compound, wherein the silicon compound is at least partially coated with a carbon coating, and at least a part of a surface of the silicon compound, a surface of the carbon coating, or both of them are coated with a composite layer that contains a composite composed of amorphous metal oxide and metal hydroxide. This provides a negative electrode active material for a non-aqueous electrolyte secondary battery that is highly stable in aqueous slurry, having a high capacity, favorable cycle performance and first efficiency.

A negative electrode active material for a non-aqueous electrolyte secondary battery, includes: negative electrode active material particles that contain a silicon compound (SiO.sub.x: 0.5?x?1.6) containing a Li compound, wherein the silicon compound is at least partially coated with a carbon coating, and at least a part of a surface of the silicon compound, a surface of the carbon coating, or both of them are coated with a composite layer that contains a composite composed of amorphous metal oxide and metal hydroxide. This provides a negative electrode active material for a non-aqueous electrolyte secondary battery that is highly stable in aqueous slurry, having a high capacity, favorable cycle performance and first efficiency.

A method for producing aluminum oxide is provided. The method uses an aluminum-oxide-forming agent containing a partially hydrolyzed aluminum alkyl compound containing an aluminum trialkyl or a mixture thereof, and a solvent. It is thus possible to produce an aluminum oxide thin film or aluminum oxide particles on or in a substrate that is not resistant to polar solvents. A method of producing a polyolefin-based polymer nanocomposite containing zinc oxide particles or aluminum oxide particles using a solution containing a partially hydrolyzed zinc alkyl or a solution containing a partially hydrolyzed aluminum alkyl is also provided. The polyolefin-based polymer nanocomposite contains a polyolefin substrate and zinc oxide particles or aluminum oxide particles, and does not contain a dispersant. The zinc oxide particles or aluminum oxide particles have an average particle size of less than 100 nm.

Provided is a method for producing a porous metal oxide. The method includes: preparing a slurry by mixing a metal source, a pore forming agent and an aqueous solvent; drying the slurry to obtain a metal oxide precursor; and sintering the metal oxide precursor to generate a porous metal oxide. The metal source is an organometallic compound or hydrolyzate thereof containing a metal that makes up the porous metal oxide; the pore forming agent is an inorganic compound that generates a gas by decomposing at a temperature equal to or lower than a temperature at which the metal oxide precursor is sintered; and the slurry is prepared using 50 parts by weight or more of the pore forming agent with respect to 100 parts by weight of the metal source.

Provided is a method for producing a porous metal oxide. The method includes: preparing a slurry by mixing a metal source, a pore forming agent and an aqueous solvent; drying the slurry to obtain a metal oxide precursor; and sintering the metal oxide precursor to generate a porous metal oxide. The metal source is an organometallic compound or hydrolyzate thereof containing a metal that makes up the porous metal oxide; the pore forming agent is an inorganic compound that generates a gas by decomposing at a temperature equal to or lower than a temperature at which the metal oxide precursor is sintered; and the slurry is prepared using 50 parts by weight or more of the pore forming agent with respect to 100 parts by weight of the metal source.

An alumina having a multimodal particle size distribution wherein at least one of the particle sizes giving local maximum values in the particle size distribution is less than 10 m, and wherein the alumina comprises 1 to 5 wt % of at least one of La and Ba.