Nanomaterials of composite metal oxides

Abstract

Exchangeable metal ions are removed from an amorphous composite metal oxide and different metal ions are introduced to manufacture a nanomaterial of composite metal oxide. Based on this method, it is possible to reliably form composite metal oxide nanomaterials over a wide range of compositions.

1 . A nanomaterial satisfying at least one of the following conditions (a), (b), (c) and (d): 
 (a) A nanomaterial of composite metal oxide which comprises an amorphous metal oxide with uniformly dispersed nanopores containing exchangeable metal ions;    (b) A nanomaterial of composite metal oxide or amorphous metal oxide wherein the composite metal oxide or the amorphous metal oxide has uniformly dispersed nanopores capable of containing metal ions;    (c) A nanomaterial of composite metal oxide or amorphous metal oxide wherein the composite metal oxide or the amorphous metal oxide has uniformly dispersed nanopores capable of selectively containing specific metal ions; and    (d) A nanomaterial of composite metal oxide or amorphous metal oxide which comprises a metal oxide insoluble in acid aqueous solution with uniformly dispersed nanopores containing metal ions soluble in acid aqueous solutions.    
     
     
         2 . The nanomaterial according to  claim 1  which satisfies condition (a).  
     
     
         3 . The nanomaterial according to  claim 1  which satisfies condition (b).  
     
     
         4 . The nanomaterial according to  claim 1  which satisfies condition (c).  
     
     
         5 . The nanomaterial according to  claim 1  which satisfies condition (d).  
     
     
         6 . The nanomaterial according to  claim 1  which comprises no organic ligand coordinated with the metal ion through a nitrogen atom, an oxygen atom, a sulfur atom or a phosphorus atom.  
     
     
         7 . The nanomaterial according to  claim 1  in the form of a thin film of from 0.5 to 100 nm in thickness.  
     
     
         8 . A material consisting of a solid and a thin film of the nanomaterial according to  claim 1  formed on the solid.  
     
     
         9 . The material according to  claim 8  wherein the solid has a surface having groups reactive with a metal alkoxide group and some or all of the reactive groups are bonded to the thin film nanomaterial.  
     
     
         10 . The material according to  claim 8  wherein the solid has positive electrical charges and some or all of the positive electrical charges are electrostatically bonded to the thin film nanomaterial.  
     
     
         11 . The material according to  claim 8  wherein the solid has groups reactive with a silicate oligomer and some or all of the reactive groups are bonded to the thin film nanomaterial.  
     
     
         12 . The material according to  claim 8  manufactured by conducting one or more times the steps of chemically adsorbing a metal alkoxide compound on the surface of the solid having groups reactive with metal alkoxide groups of the metal alkoxide compound, and rinsing the surface.  
     
     
         13 . The material according to  claim 8  manufactured by conducting one or more times the steps of: 
 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 the solid having groups reactive with metal alkoxide groups of the two metal alkoxide compounds, thereby the two metal alkoxides are adsorbed on the surface;  
 rinsing away excess metal alkoxide compounds; and  
 hydrolyzing the metal alkoxide compounds present on the solid surface to form a composite metal oxide thin film.  
 
     
     
         14 . The material according to  claim 8  manufactured by conducting at least once the steps of steps (1) and (2) below in random order on the surface of the solid having groups reactive with metal alkoxide groups: 
 step (1): bringing a solution of metal alkoxide compound capable of providing metal ions soluble in acidic aqueous solution following hydrolysis into contact with the surface of the solid, rinsing away excess metal alkoxide compound, and then hydrolyzing the metal alkoxide compound present on the solid surface to form a metal oxide thin film; and  
 step (2): bringing a solution of metal alkoxide compound capable of providing metal oxide compound insoluble in acidic aqueous solution following hydrolysis into contact with the surface of the solid, rinsing away the excess metal alkoxide compound, and hydrolyzing the metal alkoxide compound present on the solid surface to form a metal oxide thin film.  
 
     
     
         15 . The material according to  claim 8  manufactured by conducting the steps of: 
 forming an amorphous metal oxide thin film of nano-thickness on the surface of the solid having groups reactive with metal alkoxide groups,  
 immersing the amorphous metal oxide thin film in a solution comprising metal ions, and  
 rinsing away excess metal ions from the amorphous metal oxide thin film.  
 
     
     
         16 . The material according to  claim 8  manufactured by the steps of: 
 conducting one or more times the operations of bringing a metal alkoxide compound capable of providing metal oxide insoluble in water following hydrolysis into contact with the surface of a solid comprising groups reactive with metal alkoxide groups of the metal alkoxide compound whereby the metal alkoxide compound is adsorbed on the surface, rinsing away excess metal alkoxide compound, and hydrolyzing the metal alkoxide compound present on the solid surface to form a metal oxide thin film;  
 immersing the metal oxide thin film in a solution comprising metal ions; and  
 rinsing away excess metal ions from the metal oxide thin film.  
 
     
     
         17 . The material according to  claim 8  manufactured by repeating the steps of: 
 conducting one or more times the operations of bringing a metal alkoxide compound capable of providing metal oxide insoluble in water following hydrolysis into contact with the surface of a solid comprising groups reactive with metal alkoxide groups of the metal alkoxide compound whereby the metal alkoxide compound is adsorbed on the surface, rinsing away excess metal alkoxide compound, and hydrolyzing the metal alkoxide compound present on the solid surface to form a metal oxide thin film;  
 immersing the metal oxide thin film in a solution comprising metal ions; and  
 rinsing away excess metal ions from the metal oxide thin film.  
 
     
     
         18 . The material according to  claim 8  manufactured by the steps of: 
 bringing a silicate oligomer aqueous solution into contact with the surface of a solid having groups reactive with the silicate oligomer whereby the silicate oligomer is adsorbed on the surface; and  
 rinsing away the excess silicate oligomer from the surface.  
 
     
     
         19 . The material according to  claim 8  manufactured by the steps of: 
 bringing a silicate oligomer aqueous solution into contact with the surface of a solid having groups reactive with the silicate oligomer whereby the silicate oligomer is adsorbed on the surface;  
 rinsing away the excess silicate oligomer from the surface; and  
 immersing the resultant material in a solution of a metal ion different from the metal ions contained in the material to introduce the different metal ion.  
 
     
     
         20 . The material according to  claim 8  manufactured by repeating the steps of: 
 bringing a silicate oligomer aqueous solution into contact with the surface of a solid comprising groups reactive with the silicate oligomer whereby the silicate oligomer is adsorbed on the surface;  
 rinsing away the excess silicate oligomer from the surface; and  
 immersing the resultant material in a solution of metal ions different from the metal ions contained in the material to introduce these different metal ions.  
 
     
     
         21 . The material according to  claim 8  manufactured by any one of the following procedures (a)-(h): 
 (a) conducting one or more times the steps of chemically adsorbing a metal alkoxide compound on the surface of the solid having groups reactive with metal alkoxide groups, and rinsing the surface;  
 (b) conducting one or more times the steps of: 
 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 the solid having groups reactive with metal alkoxide groups of the two metal alkoxides, thereby the two metal alkoxides are adsorbed on the surface;  
 rinsing away excess metal alkoxide compounds; and hydrolyzing the metal alkoxide compound present on the solid surface to form a composite metal oxide thin film;  
 
 (c) conducting at least once the steps of steps (1) and (2) below in random order on the surface of the solid having groups reactive with metal alkoxide groups: 
 step (1): bringing a solution of metal alkoxide compound capable of providing metal ions soluble in acidic aqueous solution following hydrolysis into contact with the surface of the solid, rinsing away excess metal alkoxide compound, and then hydrolyzing the metal alkoxide compound present on the solid surface to form a metal oxide thin film; and  
 step (2): bringing a solution of metal alkoxide compound capable of providing metal oxide compound insoluble in acidic aqueous solution following hydrolysis into contact with the surface of the solid, rinsing away the excess metal alkoxide compound, and hydrolyzing the metal alkoxide compound present on the solid surface to form a metal oxide thin film.  
 
 (d) conducting the steps of: 
 forming an amorphous metal oxide thin film of nano-thickness on the surface of the solid having groups reactive with metal alkoxide groups,  
 
 immersing the amorphous metal oxide thin film in a solution comprising metal ions, and 
 rinsing away excess metal ions from the amorphous metal oxide thin film;  
 (e) conducting the steps of: 
 conducting one or more times the operations of bringing a metal alkoxide compound capable of providing metal oxide insoluble in water following hydrolysis into contact with the surface of a solid comprising groups reactive with metal alkoxide groups of the metal alkoxide compound whereby the metal alkoxide compound is adsorbed on the surface, rinsing away excess metal alkoxide compound, and hydrolyzing the metal alkoxide compound present on the solid surface to form a metal oxide thin film;  
 
 immersing the metal oxide thin film in a solution comprising metal ions; and  
 rinsing away excess metal ions from the metal oxide thin film  
 
 (f) repeating the procedure (e);  
 (g) repeating the steps of: 
 bringing a silicate oligomer aqueous solution into contact with the surface of a solid having groups reactive with the silicate oligomer whereby the silicate oligomer is adsorbed on the surface; and  
 rinsing away the excess silicate oligomer from the surface;  
 
 (h) conducting the steps of: 
 bringing a silicate oligomer aqueous solution into contact with the surface of a solid having groups reactive with the silicate oligomer whereby the silicate oligomer is adsorbed on the surface;  
 rinsing away the excess silicate oligomer from the surface; and  
 immersing the resultant material in a solution of a metal ion different from the metal ions contained in the material to introduce the different metal ion.  
 
 
     
     
         22 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid, which is manufactured by the step of immersing the material according to  claim 21  in an acidic aqueous solution to remove exchangeable metal ions.  
     
     
         23 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid, which is manufactured by the step of immersing the material according to  claim 22  in a solution of a metal ion different from the metal ions contained in the material to introduce the differing metal ion.  
     
     
         24 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid, which is manufactured by the step of immersing the material according to  claim 23  in a solution of two or more metal ions different from the metal ions contained in the material to introduce the two or more metal ions.  
     
     
         25 . The nanomaterial according to  claim 1  which is in the form of particles from 1 to 500 nm in size.  
     
     
         26 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size wherein the material comprises a metal component or a mixed valence metal oxide component obtained by reducing some or all of the metal atoms in the material according to  claim 21 .  
     
     
         27 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size wherein the material comprises a metal component or a mixed valence metal oxide component obtained by reducing some or all of the metal atoms in the material according to  claim 23 .  
     
     
         28 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size wherein the material comprises a metal component or a mixed valence metal oxide component obtained by reducing some or all of the metal atoms in the material according to  claim 24 .  
     
     
         29 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size where in the material comprises a metal chalcogenite component obtained by reacting some or all of the metal atoms in the material according to  claim 21  with a chalcogen compound.  
     
     
         30 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size wherein the material comprises a metal chalcogenite component obtained by reacting some or all of the metal atoms in the material according to  claim 23  with a chalcogen compound.  
     
     
         31 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size wherein the material comprises a metal chalcogenite component obtained by reacting some or all of the metal atoms in the material according to  claim 24  with a chalcogen compound.  
     
     
         32 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid which is manufactured by subjecting the material according to  claim 21  to a heat treatment or an oxygen plasma treatment to reduce the ion-exchange capability of the exchangeable metal ions.  
     
     
         33 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid which is manufactured by subjecting the material according to  claim 23  to a heat treatment or an oxygen plasma treatment to reduce the ion-exchange capability of the exchangeable metal ions.  
     
     
         34 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid which is manufactured by subjecting the material according to  claim 24  to a heat treatment or an oxygen plasma treatment to reduce the ion-exchange capability of the exchangeable metal ions.  
     
     
         35 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size which is obtained by re-oxidizing at least a portion of the metal component or mixed valence metal oxide component that has been reduced by the step described in  claim 26 .  
     
     
         36 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size which is obtained by re-oxidizing at least a portion of the metal component or mixed valence metal oxide component that has been reduced by the step described in  claim 27 .  
     
     
         37 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size which is obtained by re-oxidizing at least a portion of the metal component or mixed valence metal oxide component that has been reduced by the step described in  claim 28 .  
     
     
         38 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size which is obtained by subjecting the metal component or mixed valence metal oxide component that has been re-oxidized by the step described in  claim 35  to a reducing step or an alternating sequence of a reducing step and an oxidizing step in that order one or more times.  
     
     
         39 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size which is obtained by subjecting the metal component or mixed valence metal oxide component that has been re-oxidized by the step described in  claim 36  to a reducing step or an alternating sequence of a reducing step and an oxidizing step in that order one or more times.  
     
     
         40 . A material consisting of a solid and a thin film of the nanomaterial formed on the solid or in the form of particles from 1 to 500 nm in size which is obtained by subjecting the metal component or mixed valence metal oxide component that has been re-oxidized by the step described in  claim 37  to a reducing step or an alternating sequence of a reducing step and an oxidizing step in that order one or more times.