Nanoparticles, and a Method of Sol-Gel Processing

• US 20090074655A1
• Filed: 12/01/2006
• Published: 03/19/2009
• Est. Priority Date: 12/02/2005
• Status: Abandoned Application

• Current Assignee: Protech AS
• Original Assignee: Protech AS
• Inventors: Suciu, Crina Silvia
• Application Number:
  US12/085,974
• Publication Number:
  US 20090074655A1
• Time in Patent Office: Days
• US Class Current: 423/608
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01B 13/32 by oxidation or hydrolysis of elements or compounds in the liquid or solid state or in non-aqueous solution, e.g. sol-gel process
• CPC Class Codes: C01B 33/152 Preparation of hydrogels
• CPC Class Codes: C01G 1/02 Oxides
• CPC Class Codes: C01G 17/02 Germanium dioxide
• CPC Class Codes: C01G 25/02 Oxides
• CPC Class Codes: C01G 27/02 Oxides
• CPC Class Codes: C01G 35/00 Compounds of tantalum
• CPC Class Codes: C01G 53/04 Oxides; Hydroxides
• CPC Class Codes: C01P 2002/60 Compounds characterised by their crystallite size
• CPC Class Codes: C01P 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2002/88 by thermal analysis data, e.g. TGA, DTA, DSC
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C01P 2006/12 Surface area

Abstract

Methods of sol-gel processing for preparing of gels and nanoparticles are described. The invention also relates to gels and nanoparticles prepared by the described methods. A preferable embodiment describes ZrO₂ nanoparticles produced by sol gel processing by using sucrose and pectin as polymerization agents.

Claims

1-42. -42. (canceled)

43. A method of sol-gel processing, characterized in that an inorganic metal salt, pectin and mono or disaccharides are used, and that said method comprises the steps:

a) preparing a first aqueous solution comprising said inorganic metal salt, and preparing a second aqueous solution comprising said mono or disaccharides;

b) mixing the first and second solutions to a third solution at a temperature from about 80 to 100°

C.;

c) incubating the combined solution from step b) at an elevated temperature of about 80 to 200°

C. in order to gelatinize the third solution to a gel material.

44. The method according to claim 43, wherein the metal salt contains a metal selected from the group consisting of aluminium, hafnium, silicon, zirconium, lanthanum, germanium, tantalum, nickel, combinations thereof, and combinations thereof with titanium.

45. The method according to claim 43, wherein the concentration of inorganic salt in the third solution is in the range of 20 g/l to 60 g/l.

46. The method according to claim 45 wherein the concentration of inorganic salt in the third solution is 26 g/l.

47. The method according to claim 43, wherein said mono or disaccharides contains a compound selected from the group consisting of sucrose, maltose, lactose, fructose and glucose.

48. The method according to claim 43, wherein the mixing step b) is conducted by slowly pouring the first solution into the second solution in a continuous flow, and where the third solution thereafter is mixed at a rate of 120-130 rot/min.

49. A gel produced according to the method of claim 43.

50. The gel produced according to the method of claim 44.

51. The gel produced according to the method of claim 45.

52. The gel produced according to the method of claim 46.

53. The gel produced according to the method of claim 47.

54. The gel produced according to the method of claim 48.

55. A method of sol-gel processing, characterized in that an inorganic metal salt, pectin and mono or disaccharides are used, and that said method comprises the steps:

a) preparing a first aqueous solution comprising said inorganic metal salt, and preparing a second aqueous solution comprising said mono or disaccharides;

b) mixing the first and second solutions to a third solution at a temperature from about 80 to 100°

C.;

c) incubating the combined solution from step b) at an elevated temperature of about 80 to 200°

C. in order to gelatinize the third solution to a gel material;

d) thermal treatment of the gelatinized material from step c) at a temperature of from 500 to 1200°

C.

56. The method according to claim 55, wherein the thermal treatment in step d) is conducted at a temperature of 700 to 1000°

C.

57. A method in accordance with claim 55, for producing nanoparticles, wherein the nanoparticles are monodisperse.

58. A method in accordance with claim 55, for producing nanoparticles, wherein the nanoparticles are less than 100 nanometers in at least one dimension.

59. A method according to claim 55, wherein the metal salt contains a metal selected from the group consisting of aluminium, hafnium, silicon, zirconium, lanthanum, germanium, tantalum, nickel, combinations thereof, and combinations thereof with titanium.

60. A gel produced according to the method of claim 55.

61. A gel produced according to the method of claim 56.

62. A gel produced according to the method of claim 57.

63. A gel produced according to the method of claim 58.

64. A gel produced according to the method of claim 59.

65. A material in the form of nanoparticles produced according to the method of claim 55.

66. A material in the form of nanoparticles produced according to the method of claim 55.

67. A material in the form of nanoparticles produced according to the method of claim 57.

68. A material in the form of nanoparticles produced according to the method of claim 58.

69. A material in the form of nanoparticles produced according to the method of claim 59.

70. ZrO₂ nanoparticles produced by sol-gel processing by using sucrose and pectin as polymerization agents, characterized in that after thermal treatment at 900°

C. the nanoparticles are in the tetragonal phase with crystallite size of 30 nm and particle size less than 35 nm.