Patent ID: 7704549

Claim:
A method of producing a material comprising a substrate and a thin film of a nanomaterial formed on the substrate, wherein the nanomaterial satisfies at least one of the following conditions (a), (b), (c) or (d): (a) a nanomaterial of an amorphous metal oxide with uniformly distributed nanopores containing exchangeable metal ions, the nanopores in the metal oxide serving as a matrix being uniformly distributed throughout the entire nanomaterial; (b) a nanomaterial of amorphous metal oxide wherein the amorphous metal oxide has uniformly distributed nanopores capable of containing metal ions, and the nanopores in the metal oxide serve as a matrix being uniformly distributed throughout the entire nanomaterial; (c) a nanomaterial of amorphous metal oxide wherein the amorphous metal oxide has uniformly distributed nanopores capable of selectively containing specific metal ions, the nanopores in the metal oxide serving as a matrix being uniformly distributed throughout the entire nanomaterial; (d) a nanomaterial of amorphous metal oxide which comprises a metal oxide insoluble in acid amorphous solution with uniformly distributed nanopores containing metal ions soluble in acid aqueous solutions, the nanopores in the metal oxide serving as a matrix being uniformly distributed throughout the entire nanomaterial; and, wherein the method comprises conducting (i), (ii) and (iii) one or more times, and then conducting (iv): (i) bringing a mixed solution of a metal alkoxide compound capable of providing metal ions soluble in an acidic aqueous solution following hydrolysis and a metal alkoxide compound capable of providing metal oxide insoluble in water following hydrolysis into contact with the surface of a substrate having groups reactive with metal alkoxide groups of the two metal alkoxide compounds, wherein the two metal alkoxides are adsorbed on the surface; (ii) rinsing away excess metal alkoxide compounds; (iii) hydrolyzing the metal alkoxide compounds present on the substrate surface to form a thin film of a nanomaterial; and (iv) immersing the thin film of a nanomaterial in an acidic aqueous solution to remove at least a part of the metal ions soluble in the acidic aqueous solution.