CA2455428C - Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures - Google Patents
Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures Download PDFInfo
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Abstract
This invention relates to a generic process for producing a refractory oxide at a temperature below the melt-ing point of the pure refractory oxide, by reacting and dispersal-blending liquid water with at least one metal oxide reactant and a hydrogen halide composition, to produce a cat-ionically-homogeneous nanostructured colloidal mixture;
heating the mixture to a temperature at which a cationically homogeneous nanostructured solid state hydroxyhalide is pro-duced. The solid state hydroxyhalide is heated to its decom-position-temperature, by heat alone, decomposes, into a cat-ionically homogeneous nanostructured solid state oxyhalide;
and performing one of the following heating steps: (i) heating the solid state oxyhalide to a solid state oxyhalide decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refractory oxide; or (ii) heating the solid state oxyhalide to a molten state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refrac-tory oxide; or (iii) heating the solid state oxyhalide to a vapor state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refractory oxide.
heating the mixture to a temperature at which a cationically homogeneous nanostructured solid state hydroxyhalide is pro-duced. The solid state hydroxyhalide is heated to its decom-position-temperature, by heat alone, decomposes, into a cat-ionically homogeneous nanostructured solid state oxyhalide;
and performing one of the following heating steps: (i) heating the solid state oxyhalide to a solid state oxyhalide decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refractory oxide; or (ii) heating the solid state oxyhalide to a molten state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refrac-tory oxide; or (iii) heating the solid state oxyhalide to a vapor state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refractory oxide.
Description
PRODUCTION OF CATIONICALLY HOMOGENEOUS
REFRACTORY OXIDES OF NANOMETER-SCALE PARTICLE SIZE
DIAMETERS AT REDUCED TEMPERATURES
Background of the Invention This invention relates to a generic and novel process, hereinafter called the Uniform Cation Distribution Process (UCDP), for producing, at reduced temperatures, cationically homogeneous nanostructured refractory metal hydroxyhalides, metal oxyhalides and metal oxides and to the novel products thereof.
More particularly, this invention relates to a process for the manufacture, from small to commercial size quanti-ties, of refractory oxides of all compositional categories including undoped, doped, solid solution, congruent melting, incongruent melting, stoichiometric and non-stoichiometric compositions as polycrystalline, glass or three-dimensional single crystalline entities, by thermochemical reactions of hydrated homogeneously dispersed colloidal mixtures of halides or halide-oxides which form and decompose as pre-cursor complexes into refractory oxide end products.
Prior art halide hydrolysis practiced consisted of vapor phased hydrolysis, as exemplified by the below references, or by crystallizing small, thin, stoichiometric, binary oxide single crystals from programmed temperature-cooled solutions. The purity and quality of the resultant crystals were poor mainly because of inevitable solvent inclusions in the crystals and the very low acceptable crystal yields were seldom reproducible due to insufficient hydration for complete thermochemical hydrolysis of metal halides.
Some references describing thermohydrolytic prior art procedures for synthesizing refractory oxide compounds, are:
1. Popov, A.I.; Knudson, G.E., "Preparation and Properties of the Rare Earth Fluorides and Oxyfluorides,"J. Am.
Chem. Soc., 76, Feb. 1954, p. 3921.
REFRACTORY OXIDES OF NANOMETER-SCALE PARTICLE SIZE
DIAMETERS AT REDUCED TEMPERATURES
Background of the Invention This invention relates to a generic and novel process, hereinafter called the Uniform Cation Distribution Process (UCDP), for producing, at reduced temperatures, cationically homogeneous nanostructured refractory metal hydroxyhalides, metal oxyhalides and metal oxides and to the novel products thereof.
More particularly, this invention relates to a process for the manufacture, from small to commercial size quanti-ties, of refractory oxides of all compositional categories including undoped, doped, solid solution, congruent melting, incongruent melting, stoichiometric and non-stoichiometric compositions as polycrystalline, glass or three-dimensional single crystalline entities, by thermochemical reactions of hydrated homogeneously dispersed colloidal mixtures of halides or halide-oxides which form and decompose as pre-cursor complexes into refractory oxide end products.
Prior art halide hydrolysis practiced consisted of vapor phased hydrolysis, as exemplified by the below references, or by crystallizing small, thin, stoichiometric, binary oxide single crystals from programmed temperature-cooled solutions. The purity and quality of the resultant crystals were poor mainly because of inevitable solvent inclusions in the crystals and the very low acceptable crystal yields were seldom reproducible due to insufficient hydration for complete thermochemical hydrolysis of metal halides.
Some references describing thermohydrolytic prior art procedures for synthesizing refractory oxide compounds, are:
1. Popov, A.I.; Knudson, G.E., "Preparation and Properties of the Rare Earth Fluorides and Oxyfluorides,"J. Am.
Chem. Soc., 76, Feb. 1954, p. 3921.
2. Brixner, L.H., "Ferromagnetic Material Produced From Ferric Oxide And Barium Halide or Strontium Halide, And Process For Making Same," U.S. Patent 3,113,109, Dec.
3, 1963.
3. Messier, D.R.; Pask, J.A., "Kinetics of High Temper ature Hydrolysis of Magnesium Fluoride: II, Influence of Specimen Geometry and Type and of Product Layers", J. Am. Cer. Soc., Vol 48, No. 8, Sept. 1965, p. 459.
3. Messier, D.R.; Pask, J.A., "Kinetics of High Temper ature Hydrolysis of Magnesium Fluoride: II, Influence of Specimen Geometry and Type and of Product Layers", J. Am. Cer. Soc., Vol 48, No. 8, Sept. 1965, p. 459.
4. bugger. C.O., "The Growth of Pink Magnesium Aluminate (MgA1209) Single Crystals," J. of Electrochem. Soc., Vol 113, No. 3, March 1966, p. 306.
5. bugger, C.O., "Solution Growth of Oxidic Spinet and Other Oxide Single Crystals Following The Hydrolysis of Some Fluorides," J. of Phys. & Chem. of Solids Supplement, 1st Ed., Pergamon Press, New York, 1967, p.
493.
493.
6. bugger, C.O., "Method For Growing Oxide Single Crys-tals," U.S. Patent 3,595,803, July 27, 1971.
7. Utsunomya, T.; Hoshino, Y.; Sato, M., "Process of Hy-drolysis Reaction from YF3 to Y203 in a Humid Air at High Temperatures," Bulletin of the Tokyo Institute of Technology, No. 108, 1972.
Brixner, U. S. Patent No. 3,113,109, discloses a process for the production of a ferromagnetic refractory oxide material from ferric oxide and barium halide or strontium halide, in the presence of water vapor, oxygen or a mixture thereof, at 700-1350°C. In one aspect, a molten mixture of the ferric oxide and a 2-3 times stoichiometric excess of the metal ha-lide is employed as the reaction medium. In such a technique, the cation composition of the molten mixture differs from that of the oxide product, i.e., the molar ratio of the metal halide is greater in the reaction medium than its molar ratio in the refractory oxide product. Even though the product is in the form of single crystals, the product inherently is not ca n onically homogeneous because of S occluded canons from the reaction medium. Also, although transparent single crystals were obtained, they were in the form of thin substantially two dimensional platelets (10-100 microns thick and up to 2 mm in diameter); unlike three-dimensional single crystals of this invention.
The UCDP differs from the prior art refractory oxide manufacturing processes in that the refractory oxides are prOduCed r .,r r~_ r r _fr~m ~ Cat10n1Call ~~ hnmngenen»c nappstrtlCttlred substantially pure oxyhalides. The UCDP also differs in that it can produce on both large and small scales, a wide variety of novel and known crystalline refractory oxides of all compositional categories from the three states of matter [solid, liquid (molten) and vapor states).
While the UCDP is a generic process for producing pre cisely high reproducible yields of all of the refractory oxide compositional categories, there is some scientific uncertainty as to the actual precursor (intermediate) reac-tions that occur in thermochemically converting a hydrated metal halide to a refractory oxide end product; hydroxyhalide and oxyhalide complexes are reported in the literature. In addition, it is not certain if all hydrated metal halides convert to both intermediate complexes. In this invention, however, it is assumed that all hydrated metal halides are thermochemically converted to both hydroxyhalide and oxyhalide complexes only, and the hydroxyhalide and the oxy-halide complexes are considered to be low temperature 500°C) and high temperature complexes, respectively. A
chemical complex composition of this invention consists of one or more metal halides bonded to oxygen, hydroxyl groups or both. Thus, hydroxyhalides and oxyhalides are chemical complexes which may exhibit an overall excess electric charge(s).
In the context of this invention, the term "hydrolysis"
as used herein is the chemical reaction of a substance with liquid water or its ions.
The use of liquid water as a reactant is a substantial improvement over the prior art technique of using indetermi nate moist gases or waters of crystallization as the water source reactant . The halides used in the UCDP are not only fully hydrated, ~.ahich ensures complete hydrolytic reactions, but also the liquid water, of appropriate pH, is a homogeneous reactant-mixing medium. The combined simul-taneous chemical exothermic halide-hydration reaction and homogeneous physical water-mixing produces a homogeneously dispersed colloidal reactant mixture from which all the UCDP
precursors and refractory oxides are produced.
The term "refractory oxide" is used herein in its conventional sense. It is a metal oxide, usually of one or more metal rations and which has a fusion point, i.e., it becomes molten upon heating. In this invention, the Chemical Periodic Table metals of Groups IA - VA, IB - VIIB and VIII, the lanthanides, and the actinides, thorium and uranium can be used to produce metal halides and oxides. A ration is a positively charged ion.
The term "canonically homogeneous" means that the re-fractory oxide is substantially free of occluded extraneous rations.
A refractory oxide is called either a nanostructured or nanophased composition when its colloidal particle size dia-meters are less than about a hundred nanometers. These nano-phased materials can be used to produce new classes of ceram ics and ceramic composites which demonstrate enhanced magnet ic, electronic and mechanical properties and can lead to ad vanced materials, engineering breakthroughs and new techno logies.
The term "substantially pure" as used herein means the actual cationic composition thereof differs by no more than about 5 wt~ from theoretical based upon chemical analysis, preferably less than 2 wto, and most preferably, e.g., in the case of refractory oxides to be used in a laser or a super-conductor, 0.25 wto or less.
Objects of the Invention A primary object of this invention is to provide a novel, generic and highly reliable process which, on a com mercial scale, can produce refractory oxides that are can onically homogeneous, nanostructured and substantially pure.
Another object is the provision of a process for the manufacture of such refractory oxides at temperatures ranging from 100°C to 1500°C below their pure melting points.
Yet another object is the manufacture of novel refrac-tory oxide compositions.
A further object of this invention is to provide a pro cess which markedly reduces or eliminates the prior art dis advantages attendant to refractory oxide materials prepara tion.
Still further objects of advantages and features of this invention will become apparent upon consideration of the following detailed description thereof.
Summary of the Invention In a process aspect, this invention relates to a pro-cess which comprises producing a ca n onically homogeneous nanostructured substantially pure metal oxyhalide which is thermochemically decomposes, by heat alone, into its refrac-tory oxide.
In a preferred process aspect, this invention relates to a generic process for producing a refractory oxide which comprises (a) reacting and dispersal-blending liquid water with at least one metal oxide reactant and a hydrogen halide composition to produce a ca n onically-homogeneous nano-structured colloidal mixture; (b) heating the colloidal mixture to produce a solid state metal hydroxyhalide; (c) further heating the metal hydroxyhalide to a higher tem-perature at which it chemically decomposes, by heat alone, into a ca n onically-homogeneous nanostructured solid state metal oxyhalide; and performing one of the following heating steps: (i) heating the metal oxyhalide to a solid state de-composition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; (ii) heating the metal oxy-halide to a molten state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide;
(iii) heating the metal oxyhalide to a vapor state decomposi-tion-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
In a compositional aspect, this invention relates to can onically homogeneous nanostructured refractory oxides, most of which are transparent and many of which have one or both of electrostatic and magnetic properties.
In another compositional aspect, this invention relates to chemically novel refractory oxides.
In yet another compositional aspect, this invention re-lates to the hydroxyhalide and oxyhalide precursors of the refractory oxides of this invention.
Detailed Description of the Invention The UCDP is an extraordinary and powerful manufacturing process because of its generic capability to manufacture vir-tually any refractory oxide that can be produced at atmospheric pressure. Additionally, UCDP's novel products' properties enable the products to be used in all refractory oxide procedures and applications such as sensors, filters, photonics, wave-guides, high strength near-net-shape structures, superconductors, insulators, catalysts, films, fibers nuclear waste management, etc.
As illustrated in the examples below, the number of different cations and their concentrations in the end products can vary widely. The purity, quality and homo geneity of the end products are very high and precisely reproducible.
In a preferred aspect, the refractory oxides of this invention are produced from a metal oxyhalide precursor thereto selected from the group consisting of:
a) Bal-~p+s+o.sXJRo.s~PDsUXMgi-yDyAllo-cZ+w~JZQo.~sw~m-o.sgGg DS=Ca, Sr, Pb; G=F, Cl; Q=Si, Ge;
J=Cr, Ga, Ti, Mn, V, Fe, Co; U=Na, K;
Dy=Co, Cu, Ge, Ni, Zn; R=Y, lanthanides;
g~33.7; 0<_p<_0.6; O~s<_1.0;
0<-x1.2; 0-<y<_l; O~z~0.6; O~w<7.5;
b ) Baz-pNal-(x> KxRo. 6~PNbs-yTayOls-o. sgGg G = F, Cl; R = Y, Lanthanides gS29.7; O~p~0.6; O~x~l.0; 0<_y<_5.0;
C) Sr1-(x+2p+z)BaxUpRp-Jp,n7zNb2-yTay~6-O.SgGg G = F, C1; U = Na, K;
J = Cr, Fe; R = Y, Lanthanides;
g~1.7; O~p~0.18; O~X<_1; 0<_y<_2; O~z~0.18;
d) Bal_xDXTii-(y+o.;sZ)Jz~ry03-o.sgGg D = Sr, Pb, Ca;
G = F, Cl; J = Fe, Cr g~5.7; O~x~l; 0<_Y_1; O~z~0.1;
e) KTai-cx+o.6yNbxJvO3-0.5gGg G = F, C1; J = Cr, Fe;
g<5.7; 0<x<1; 0<y<0.1;
Ll~-(x+z+d) D0. SxD0.5dJ0.33zTa1-yNbyO3-O. SgGg Dx = Ni, Co, Fe, Mg; G = F, C1;
Dd= Ni, Co, Cu, Zn; J = Cr, Fe; G = F, C1 05d~0.12; g~5.7; O~x~l; O~y~l; O~z~0.4;
g) Mgi-cx+y+z) DzJo. b~yRo.6~xOi-o. sgGg D = Ni, Co, Fe, Cu, Ge, Zn;
J = Cr, Fe, Ti; G = F, C1; R = Lanthanides C~~1 . 7 ; D~XCO . 015; V ~y~l; U~Z~1;
h) Mgl-zDzAl2-tx+v)RxJy~4-o.sgGg G = F, Cl; D = Co, Ni, Cu, Zn, Ge J = Co, Cr, Fe, Mn, Ti, V; R = Lanthanides g<7.7; 0<x~l; 0<y~2; 0<z51;
i) Pb2-zDZKl-x)NaxNbs-vTayOls-o.sgGg DZ = Ba, Ca; G = F, Cl;
g<29.7; 0<-x<_1, O~y~S, O~z~2;
) Y2- (x+dl RxJa03-o. sgGg G = F, C1; R = Lanthanides;
J = Cr, Ga, Ti, Fe, A1, V, Co, Ni, Cu, Mn;
O~d~0.15; g<-5.7; O~x~2;
k ) A12- (x+v+w> RxJvQo. ~sw03-o. sgGg J = Cr, Ga, Ti, Fe, V, Co, Mn;
G=F, C1; Q= Si, Ge, Sn; R = Lanthanides;
g~5.7; O~x~0.12; O~y~0.12; O~w<_1.8;
Brixner, U. S. Patent No. 3,113,109, discloses a process for the production of a ferromagnetic refractory oxide material from ferric oxide and barium halide or strontium halide, in the presence of water vapor, oxygen or a mixture thereof, at 700-1350°C. In one aspect, a molten mixture of the ferric oxide and a 2-3 times stoichiometric excess of the metal ha-lide is employed as the reaction medium. In such a technique, the cation composition of the molten mixture differs from that of the oxide product, i.e., the molar ratio of the metal halide is greater in the reaction medium than its molar ratio in the refractory oxide product. Even though the product is in the form of single crystals, the product inherently is not ca n onically homogeneous because of S occluded canons from the reaction medium. Also, although transparent single crystals were obtained, they were in the form of thin substantially two dimensional platelets (10-100 microns thick and up to 2 mm in diameter); unlike three-dimensional single crystals of this invention.
The UCDP differs from the prior art refractory oxide manufacturing processes in that the refractory oxides are prOduCed r .,r r~_ r r _fr~m ~ Cat10n1Call ~~ hnmngenen»c nappstrtlCttlred substantially pure oxyhalides. The UCDP also differs in that it can produce on both large and small scales, a wide variety of novel and known crystalline refractory oxides of all compositional categories from the three states of matter [solid, liquid (molten) and vapor states).
While the UCDP is a generic process for producing pre cisely high reproducible yields of all of the refractory oxide compositional categories, there is some scientific uncertainty as to the actual precursor (intermediate) reac-tions that occur in thermochemically converting a hydrated metal halide to a refractory oxide end product; hydroxyhalide and oxyhalide complexes are reported in the literature. In addition, it is not certain if all hydrated metal halides convert to both intermediate complexes. In this invention, however, it is assumed that all hydrated metal halides are thermochemically converted to both hydroxyhalide and oxyhalide complexes only, and the hydroxyhalide and the oxy-halide complexes are considered to be low temperature 500°C) and high temperature complexes, respectively. A
chemical complex composition of this invention consists of one or more metal halides bonded to oxygen, hydroxyl groups or both. Thus, hydroxyhalides and oxyhalides are chemical complexes which may exhibit an overall excess electric charge(s).
In the context of this invention, the term "hydrolysis"
as used herein is the chemical reaction of a substance with liquid water or its ions.
The use of liquid water as a reactant is a substantial improvement over the prior art technique of using indetermi nate moist gases or waters of crystallization as the water source reactant . The halides used in the UCDP are not only fully hydrated, ~.ahich ensures complete hydrolytic reactions, but also the liquid water, of appropriate pH, is a homogeneous reactant-mixing medium. The combined simul-taneous chemical exothermic halide-hydration reaction and homogeneous physical water-mixing produces a homogeneously dispersed colloidal reactant mixture from which all the UCDP
precursors and refractory oxides are produced.
The term "refractory oxide" is used herein in its conventional sense. It is a metal oxide, usually of one or more metal rations and which has a fusion point, i.e., it becomes molten upon heating. In this invention, the Chemical Periodic Table metals of Groups IA - VA, IB - VIIB and VIII, the lanthanides, and the actinides, thorium and uranium can be used to produce metal halides and oxides. A ration is a positively charged ion.
The term "canonically homogeneous" means that the re-fractory oxide is substantially free of occluded extraneous rations.
A refractory oxide is called either a nanostructured or nanophased composition when its colloidal particle size dia-meters are less than about a hundred nanometers. These nano-phased materials can be used to produce new classes of ceram ics and ceramic composites which demonstrate enhanced magnet ic, electronic and mechanical properties and can lead to ad vanced materials, engineering breakthroughs and new techno logies.
The term "substantially pure" as used herein means the actual cationic composition thereof differs by no more than about 5 wt~ from theoretical based upon chemical analysis, preferably less than 2 wto, and most preferably, e.g., in the case of refractory oxides to be used in a laser or a super-conductor, 0.25 wto or less.
Objects of the Invention A primary object of this invention is to provide a novel, generic and highly reliable process which, on a com mercial scale, can produce refractory oxides that are can onically homogeneous, nanostructured and substantially pure.
Another object is the provision of a process for the manufacture of such refractory oxides at temperatures ranging from 100°C to 1500°C below their pure melting points.
Yet another object is the manufacture of novel refrac-tory oxide compositions.
A further object of this invention is to provide a pro cess which markedly reduces or eliminates the prior art dis advantages attendant to refractory oxide materials prepara tion.
Still further objects of advantages and features of this invention will become apparent upon consideration of the following detailed description thereof.
Summary of the Invention In a process aspect, this invention relates to a pro-cess which comprises producing a ca n onically homogeneous nanostructured substantially pure metal oxyhalide which is thermochemically decomposes, by heat alone, into its refrac-tory oxide.
In a preferred process aspect, this invention relates to a generic process for producing a refractory oxide which comprises (a) reacting and dispersal-blending liquid water with at least one metal oxide reactant and a hydrogen halide composition to produce a ca n onically-homogeneous nano-structured colloidal mixture; (b) heating the colloidal mixture to produce a solid state metal hydroxyhalide; (c) further heating the metal hydroxyhalide to a higher tem-perature at which it chemically decomposes, by heat alone, into a ca n onically-homogeneous nanostructured solid state metal oxyhalide; and performing one of the following heating steps: (i) heating the metal oxyhalide to a solid state de-composition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; (ii) heating the metal oxy-halide to a molten state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide;
(iii) heating the metal oxyhalide to a vapor state decomposi-tion-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
In a compositional aspect, this invention relates to can onically homogeneous nanostructured refractory oxides, most of which are transparent and many of which have one or both of electrostatic and magnetic properties.
In another compositional aspect, this invention relates to chemically novel refractory oxides.
In yet another compositional aspect, this invention re-lates to the hydroxyhalide and oxyhalide precursors of the refractory oxides of this invention.
Detailed Description of the Invention The UCDP is an extraordinary and powerful manufacturing process because of its generic capability to manufacture vir-tually any refractory oxide that can be produced at atmospheric pressure. Additionally, UCDP's novel products' properties enable the products to be used in all refractory oxide procedures and applications such as sensors, filters, photonics, wave-guides, high strength near-net-shape structures, superconductors, insulators, catalysts, films, fibers nuclear waste management, etc.
As illustrated in the examples below, the number of different cations and their concentrations in the end products can vary widely. The purity, quality and homo geneity of the end products are very high and precisely reproducible.
In a preferred aspect, the refractory oxides of this invention are produced from a metal oxyhalide precursor thereto selected from the group consisting of:
a) Bal-~p+s+o.sXJRo.s~PDsUXMgi-yDyAllo-cZ+w~JZQo.~sw~m-o.sgGg DS=Ca, Sr, Pb; G=F, Cl; Q=Si, Ge;
J=Cr, Ga, Ti, Mn, V, Fe, Co; U=Na, K;
Dy=Co, Cu, Ge, Ni, Zn; R=Y, lanthanides;
g~33.7; 0<_p<_0.6; O~s<_1.0;
0<-x1.2; 0-<y<_l; O~z~0.6; O~w<7.5;
b ) Baz-pNal-(x> KxRo. 6~PNbs-yTayOls-o. sgGg G = F, Cl; R = Y, Lanthanides gS29.7; O~p~0.6; O~x~l.0; 0<_y<_5.0;
C) Sr1-(x+2p+z)BaxUpRp-Jp,n7zNb2-yTay~6-O.SgGg G = F, C1; U = Na, K;
J = Cr, Fe; R = Y, Lanthanides;
g~1.7; O~p~0.18; O~X<_1; 0<_y<_2; O~z~0.18;
d) Bal_xDXTii-(y+o.;sZ)Jz~ry03-o.sgGg D = Sr, Pb, Ca;
G = F, Cl; J = Fe, Cr g~5.7; O~x~l; 0<_Y_1; O~z~0.1;
e) KTai-cx+o.6yNbxJvO3-0.5gGg G = F, C1; J = Cr, Fe;
g<5.7; 0<x<1; 0<y<0.1;
Ll~-(x+z+d) D0. SxD0.5dJ0.33zTa1-yNbyO3-O. SgGg Dx = Ni, Co, Fe, Mg; G = F, C1;
Dd= Ni, Co, Cu, Zn; J = Cr, Fe; G = F, C1 05d~0.12; g~5.7; O~x~l; O~y~l; O~z~0.4;
g) Mgi-cx+y+z) DzJo. b~yRo.6~xOi-o. sgGg D = Ni, Co, Fe, Cu, Ge, Zn;
J = Cr, Fe, Ti; G = F, C1; R = Lanthanides C~~1 . 7 ; D~XCO . 015; V ~y~l; U~Z~1;
h) Mgl-zDzAl2-tx+v)RxJy~4-o.sgGg G = F, Cl; D = Co, Ni, Cu, Zn, Ge J = Co, Cr, Fe, Mn, Ti, V; R = Lanthanides g<7.7; 0<x~l; 0<y~2; 0<z51;
i) Pb2-zDZKl-x)NaxNbs-vTayOls-o.sgGg DZ = Ba, Ca; G = F, Cl;
g<29.7; 0<-x<_1, O~y~S, O~z~2;
) Y2- (x+dl RxJa03-o. sgGg G = F, C1; R = Lanthanides;
J = Cr, Ga, Ti, Fe, A1, V, Co, Ni, Cu, Mn;
O~d~0.15; g<-5.7; O~x~2;
k ) A12- (x+v+w> RxJvQo. ~sw03-o. sgGg J = Cr, Ga, Ti, Fe, V, Co, Mn;
G=F, C1; Q= Si, Ge, Sn; R = Lanthanides;
g~5.7; O~x~0.12; O~y~0.12; O~w<_1.8;
8 1 ) Y3-xRxAlS- (y+w) JyQO. 75w012-0. SgGg G = F, C1; R = Lanthanides J = Cr, Ga, Ti, Fe, V, Co, Mn;
Q = Si, Ge g_<23.7; O~w<_5; O~x<3; 0-<<y~0.5;
m) Y3-xRxFeS_yJyO~2-O.sgGg G = F, C1; R = Lanthanides J = Cr, Al, Ga, Co, Mn;
g<_23.7; 05x<-3; 0<-y<-5; and where "U" "D" "R" "J" and "Q" are one or more: uni-valent, divalent, rare-earth, trivalent and tetravalent ca n ons, respectively; and, "G" is one or more halogen ions;
and, each lower-case letter of the formulae denotes a variable numerical value of the atomic ratio of that chemical element in the composition. The preferred refractory oxides of this invention otherwise correspond to the above formulae without the Gg element.
UCDP compositions are manufactured by the below thermo chemical Reactions I-IV. For example, in the case of yttrium oxide (Y203), the overall reaction equation is:
2YF3 (p) + 3H20 (1) --> Yz03 (c) + 6HF (g) The hydrogen fluoride product weight percent loss is ca. 350.
Reaction I: YF3 hydration (chemisorption ca.20°C to ca.
150°C) 2YF3(p) + 3H20(1) --> 2[YF3~1.5H20] (c) + heat.
Reactio:. II: Thermochemical halide hydrolytic reactions and shifting chemical equilibria cause the formation of a solid state hydroxyfluoride complex from ca. 150°C to ca. 500°C.
2 [YF3~1 .5H20] (c) --> YZ (OH) 3F3 (c) + 3HF (g) Reaction IIA: Oxide-hydrogen halide hydrolytic group alter-nate reaction to Reactions I & II.
Q = Si, Ge g_<23.7; O~w<_5; O~x<3; 0-<<y~0.5;
m) Y3-xRxFeS_yJyO~2-O.sgGg G = F, C1; R = Lanthanides J = Cr, Al, Ga, Co, Mn;
g<_23.7; 05x<-3; 0<-y<-5; and where "U" "D" "R" "J" and "Q" are one or more: uni-valent, divalent, rare-earth, trivalent and tetravalent ca n ons, respectively; and, "G" is one or more halogen ions;
and, each lower-case letter of the formulae denotes a variable numerical value of the atomic ratio of that chemical element in the composition. The preferred refractory oxides of this invention otherwise correspond to the above formulae without the Gg element.
UCDP compositions are manufactured by the below thermo chemical Reactions I-IV. For example, in the case of yttrium oxide (Y203), the overall reaction equation is:
2YF3 (p) + 3H20 (1) --> Yz03 (c) + 6HF (g) The hydrogen fluoride product weight percent loss is ca. 350.
Reaction I: YF3 hydration (chemisorption ca.20°C to ca.
150°C) 2YF3(p) + 3H20(1) --> 2[YF3~1.5H20] (c) + heat.
Reactio:. II: Thermochemical halide hydrolytic reactions and shifting chemical equilibria cause the formation of a solid state hydroxyfluoride complex from ca. 150°C to ca. 500°C.
2 [YF3~1 .5H20] (c) --> YZ (OH) 3F3 (c) + 3HF (g) Reaction IIA: Oxide-hydrogen halide hydrolytic group alter-nate reaction to Reactions I & II.
9 Y203 + 3HF --> Y2 (OH) 3F3 Reaction III: Increasing temperature (>500°C), shifting chemical equilibria and solid state activated hydroxyfluoride decomposition causes the for-mation of a solid state oxyfluoride complex at ca . 1000°C .
YZ (OH) 3F3 (C) --> Y2~3F33 (c) + 3H+(g) Reaction IIIA: Solid state activated oxyhalide complex decomposition to refractory end product at ca. 1100°C & 80 hrs.
Y2~3F33 ( C ) --> Y2O3 ( C ) ~- 3 F ( g ) Reaction IV: Molten or vapor state isothermal y~O~F33-(~i,g) decomposition temperature at ca. 1550°C pro-duces transparent Y203 crystals.
YzO3F33 (m, g) to fcrm YZO3 (c) + 3F (g) In the above equations, p=powder; 1=liquid; g=gas; c=crys-talline; m=molten; and --> = reaction direction and heating.
The proposed Reactions I-IV are assumed to be molecular complex reactions that proceed by shifting ehemic:al equi-libria irreversibly to the right to produce refractory oxides.
A general implementation of the above UCDP manufactur-ing thermochemical reactions is as follows:
1. Write the appropriate chemical equations and calculate:
a) reactant weights;
b) product weight percent loss..
2. Use at least one metal oxide and a hydrogen halide com-position. Calculate and weigh out each reactant; se-quentially, homogeneously dry-mix the reactants, mix with water to form a homogeneously dispersed colloidal state, dry the uniform mixture up to about 150°C and pulverize and sieve the mixture through a 200 mesh screen (Reaction I).
3. Place the powdered composition in a pre-weighed empty crucible, weigh and program heat the crucible to the appropriate temperature and hold for an appropriate time which ensures complete solid state hydroxyhalide complex formation (Reaction II).
4. Cool the furnace; weigh the crucible and determine the composition's wto loss; pulverize the composition and sieve through 200 mesh screen. Use X-ray analysis to confirm that the precursor complex phase has completely formed.
5. Compact and place the powdered composition in a pre-weighed empty crucible, weigh and program heat the cru-cible to a Reaction III temperature and maintain the contents at that temperature for a period of time suf ficient to ensure the oxyhalide reaction has gone to completion. Determine wt o loss, pulverize, sieve and X-ray to confirm that the presence of the precursor complex phase.
6 Compact the Step 5 composition and program heat it to a Reaction IIIA temperature. Maintain a constant (isothermal) temperature for a sufficient time period to ensure the decomposition of the solid state activated oxyhalide complex.
7. Compact the Step 5 composition and program heat it to a ReaCtiOii i vJ mvi teii t2mperatiir2 .
8. Program cool the molten temperature to a lower molten or solidification temperature; or, isothermally maintain or program cool an end product seed crystal in contact with the molten complex.
9. Heat the compacted composition from Step 5 to within a temperature range from about twenty (20°C) Celsius de grees to three hundred (300°C) Celsius degrees above the Reaction IV initial molten temperature to obtain a vapor state temperature.
YZ (OH) 3F3 (C) --> Y2~3F33 (c) + 3H+(g) Reaction IIIA: Solid state activated oxyhalide complex decomposition to refractory end product at ca. 1100°C & 80 hrs.
Y2~3F33 ( C ) --> Y2O3 ( C ) ~- 3 F ( g ) Reaction IV: Molten or vapor state isothermal y~O~F33-(~i,g) decomposition temperature at ca. 1550°C pro-duces transparent Y203 crystals.
YzO3F33 (m, g) to fcrm YZO3 (c) + 3F (g) In the above equations, p=powder; 1=liquid; g=gas; c=crys-talline; m=molten; and --> = reaction direction and heating.
The proposed Reactions I-IV are assumed to be molecular complex reactions that proceed by shifting ehemic:al equi-libria irreversibly to the right to produce refractory oxides.
A general implementation of the above UCDP manufactur-ing thermochemical reactions is as follows:
1. Write the appropriate chemical equations and calculate:
a) reactant weights;
b) product weight percent loss..
2. Use at least one metal oxide and a hydrogen halide com-position. Calculate and weigh out each reactant; se-quentially, homogeneously dry-mix the reactants, mix with water to form a homogeneously dispersed colloidal state, dry the uniform mixture up to about 150°C and pulverize and sieve the mixture through a 200 mesh screen (Reaction I).
3. Place the powdered composition in a pre-weighed empty crucible, weigh and program heat the crucible to the appropriate temperature and hold for an appropriate time which ensures complete solid state hydroxyhalide complex formation (Reaction II).
4. Cool the furnace; weigh the crucible and determine the composition's wto loss; pulverize the composition and sieve through 200 mesh screen. Use X-ray analysis to confirm that the precursor complex phase has completely formed.
5. Compact and place the powdered composition in a pre-weighed empty crucible, weigh and program heat the cru-cible to a Reaction III temperature and maintain the contents at that temperature for a period of time suf ficient to ensure the oxyhalide reaction has gone to completion. Determine wt o loss, pulverize, sieve and X-ray to confirm that the presence of the precursor complex phase.
6 Compact the Step 5 composition and program heat it to a Reaction IIIA temperature. Maintain a constant (isothermal) temperature for a sufficient time period to ensure the decomposition of the solid state activated oxyhalide complex.
7. Compact the Step 5 composition and program heat it to a ReaCtiOii i vJ mvi teii t2mperatiir2 .
8. Program cool the molten temperature to a lower molten or solidification temperature; or, isothermally maintain or program cool an end product seed crystal in contact with the molten complex.
9. Heat the compacted composition from Step 5 to within a temperature range from about twenty (20°C) Celsius de grees to three hundred (300°C) Celsius degrees above the Reaction IV initial molten temperature to obtain a vapor state temperature.
10. Obtain a refractory oxide end product compound by: a) maintaining, isothermally, the higher Step 9 temper-ature for a sufficient time period to ensure that the shifting chemical equilibria caused by the gas-forming reactions and the consuming decomposition reactions of the vapor state activated complexes to solid oxide are completed.
11 11. Perform X-ray, chemical and infrared absorption analyses on the end product composition.
12. Anneal, if necessary to impart a specific property to the refractory oxide, in an appropriate gaseous envi-ronment, such as dry or moist air, O2, H2, Nz, CO/COz, HF, He or Ar.
The temperatures at which the Reactions I-IV occur in the process of this invention range from about ambient (20°C) temperature for the initial reaction to about 1700°C for the final refractory oxide production step and at virtually any pressure which does not adversely affect shifting chemical equilibria reactions. The length of time for a complex to decompose is principally a function of the complex composi-tion, the quantity of the complex and the decomposition temperature employed. The reaction time periods are usually maintained for a plurality of hours at designated temperatures to ensure that a complete complex reaction is achieved. These reaction parameters can be empirically esti-mated and roughly in situ determined. More sophisticated known in situ thermoanalytical techniques can be used to de-termine the optimum UCDP reaction kinetic parameters, which can then be precisely reproduced.
The specific decomposition-temperatures used depend upon the specific oxyhalide being thermochemically decomposed but generally is about 100°C to 1500°C below the true melting point of the corresponding refractory oxide. Ordinarily the temperatures are maintained substantially constant, e.g., within about 5°C and preferably within about 1°C. The ge neric process of this invention, therefore, provides a precise, highly reproducible yield process for manufacturing all refractory oxide compositional categories at lower tem-peratures than heretofore possible and produces refractory oxide end products which are cationically homogeneous, with manometer-scale particle sizes, of high quality and purity as verified by chemical and/or X-ray analyses. The invention also provides a method for the manufacture not only of refractory oxide compositions which are presently commer-d ally available but also heretofore commercially unavailable known refractory oxides. The process also enables the manu-facture of a potentially inexhaustible number of novel refractory compositions, including those disclosed herein.
In the manufacture of refractory oxides by the UCPD, fluorides, chlorides and fluoride-chloride combinations are used. Also additional reactants may be used, such as other halides, hydroxides, carbonates, nitrates and sulfates;
whether anhydrous or hydrated. Although ultrapure pure reactants may be used to produce refractory oxides of the highest of purity, off-the-shelf (reagent grade) chemical re-actants generally are used because they become highly purified during the complex formation-decomposition reac-tions. Thus, UCDP refractory oxide end products can be manufactured very economically.
In the UCDP's chemical vapor deposition procedure, chlorides are generally used rather than fluorides because chlorides melt at much lower temperatures and exhibit much higher vapor pressures at given temperature than fluorides.
Each example below exhibits a decomposition-temperature range derived by heating a small sample reactant mixture to each of the temperatures at which a chemical conversion occurs and maintaining the sample at each of those temper atures for at least about three hours. Microscopic exami nations of the compositions can identify the molten state ranges.
The temperatures at which the Reactions I-IV occur in the process of this invention range from about ambient (20°C) temperature for the initial reaction to about 1700°C for the final refractory oxide production step and at virtually any pressure which does not adversely affect shifting chemical equilibria reactions. The length of time for a complex to decompose is principally a function of the complex composi-tion, the quantity of the complex and the decomposition temperature employed. The reaction time periods are usually maintained for a plurality of hours at designated temperatures to ensure that a complete complex reaction is achieved. These reaction parameters can be empirically esti-mated and roughly in situ determined. More sophisticated known in situ thermoanalytical techniques can be used to de-termine the optimum UCDP reaction kinetic parameters, which can then be precisely reproduced.
The specific decomposition-temperatures used depend upon the specific oxyhalide being thermochemically decomposed but generally is about 100°C to 1500°C below the true melting point of the corresponding refractory oxide. Ordinarily the temperatures are maintained substantially constant, e.g., within about 5°C and preferably within about 1°C. The ge neric process of this invention, therefore, provides a precise, highly reproducible yield process for manufacturing all refractory oxide compositional categories at lower tem-peratures than heretofore possible and produces refractory oxide end products which are cationically homogeneous, with manometer-scale particle sizes, of high quality and purity as verified by chemical and/or X-ray analyses. The invention also provides a method for the manufacture not only of refractory oxide compositions which are presently commer-d ally available but also heretofore commercially unavailable known refractory oxides. The process also enables the manu-facture of a potentially inexhaustible number of novel refractory compositions, including those disclosed herein.
In the manufacture of refractory oxides by the UCPD, fluorides, chlorides and fluoride-chloride combinations are used. Also additional reactants may be used, such as other halides, hydroxides, carbonates, nitrates and sulfates;
whether anhydrous or hydrated. Although ultrapure pure reactants may be used to produce refractory oxides of the highest of purity, off-the-shelf (reagent grade) chemical re-actants generally are used because they become highly purified during the complex formation-decomposition reac-tions. Thus, UCDP refractory oxide end products can be manufactured very economically.
In the UCDP's chemical vapor deposition procedure, chlorides are generally used rather than fluorides because chlorides melt at much lower temperatures and exhibit much higher vapor pressures at given temperature than fluorides.
Each example below exhibits a decomposition-temperature range derived by heating a small sample reactant mixture to each of the temperatures at which a chemical conversion occurs and maintaining the sample at each of those temper atures for at least about three hours. Microscopic exami nations of the compositions can identify the molten state ranges.
13 A variety of furnaces and techniques can be used to manufacture refractory oxide compositions by the UCDP from solid, molten, or vapor states. The furnace-pressure capa-bilities can range from negative pressures (vacuums) to overpressures greater than one atmosphere. Compacted reactant-mixture billets or platinum, ceramic or molybdenum crucibles can be used to hold the reacting compositions in the appropriate gas environments such as air, nitrogen, oxygen and hydrogen.
Each example below is either a specific representative derivative compound of the parent compound or a specific par-ent compound selected for manufacture from the immediate below general formula group series. Each group is of similar chemical-type of compounds, within given concentration range and suggests similar UCDP temperature-range manufacture. No new X-ray lattice constants were determined for doped and solid solution compounds if a JCPD X-ray card does not exist.
The lattice constants of these compounds are reported as the standard JCPD values for identical constituent compounds but of different concentrations. In general, a parent compound is one in which the elements' atomic ratios (subscript numbers) are integers.
In the examples, air at atmospheric pressure, was the furnace gas environment used; and, lanthanides are the atomic number elements 57 to 71 of the Chemical Periodic Table.
GENERAL FORMULA GROUP SERIES
The novel refractory oxides described below are pro duced from a metal oxyhalide precursor, whose structure otherwise corresponds thereto except for the absence of the Gg element, selected from the group consisting of:
Each example below is either a specific representative derivative compound of the parent compound or a specific par-ent compound selected for manufacture from the immediate below general formula group series. Each group is of similar chemical-type of compounds, within given concentration range and suggests similar UCDP temperature-range manufacture. No new X-ray lattice constants were determined for doped and solid solution compounds if a JCPD X-ray card does not exist.
The lattice constants of these compounds are reported as the standard JCPD values for identical constituent compounds but of different concentrations. In general, a parent compound is one in which the elements' atomic ratios (subscript numbers) are integers.
In the examples, air at atmospheric pressure, was the furnace gas environment used; and, lanthanides are the atomic number elements 57 to 71 of the Chemical Periodic Table.
GENERAL FORMULA GROUP SERIES
The novel refractory oxides described below are pro duced from a metal oxyhalide precursor, whose structure otherwise corresponds thereto except for the absence of the Gg element, selected from the group consisting of:
14 1 ) Bal-(2p+s+0. sx) UpRpDSAxMgl-yDyAllo- (Z+w) JZQo.
~sw~m 2 ) Ba2-apNal- (x-p) KxRpNbs-yTayOis 3 ) S rl- (x+2p) BaxUpRpJO. 57Nb2_yTay~g 4 ) Bal-xDXTil_ (y+o.~sZ) Jzzry03 5) KTal-(x+o.6y)NbxJy03 L11-(x+z+d) D0.5xD0.5dJ0.33zTa1-yNby~3 7 ) Mgl-(x+y+z) DzJo.6'7yRo.67x~
8 ) Mg1-xDXAl2-yJy09 9 ) Pb2-ZDZKi-xNaxNbs-yTayOls 10 ) YZ-xRXJd03 11 ) Pal2- (x+y+w) RxJyQ0.75w~3 12 ) Y3-xRxAls (y+w) JyQo.75w~12 13 ) Y3-xRxFes-yJy012 #here "U", "D", "R", "J" and "Q" are as defined hereinabove.
The UCDP manufacturing procedure, which illustrates Reactions I-IV, as already set forth, is responsible for the production of an assortment of compositions. The below examples a re given to exemplify the UCDP and the scope of the invention and are not intended to be limiting in the sense of the scope of the invention.
EXAMPLE I
General Formula Bal_(p+S+o.sx)Ro.67pDsUxMgi-yDyAllo-(Z+w)JzQo.7swW 7 R=Y, lanthanides; DS=Ca, Sr, Pb; U=K, Na;
Dy=Co, Cu, Ge, Ni, Zn; J=Cr, Ga, Ti, Mn, V, Fe, Co;
Q=Si, Ge;
0<_p<_0.6; 0.05SsS1; O~w<_7.5;
0<_x<_1.2; 0<-y<-1; 0<-z<_0.6 Specific End Product Compound Bao.9oNao.osNdo.osMg~119.siaCro.oo6Tio.oaCm (c) (New Composition) The temperature of a three gram reactant mixture, con-sisting of, in mole %, 3.12BaFz + 0.02NaF + 0.02NdF3 + 3.5MgFz + 20.6A1F3 + 6.9AIz03 + O.O1Ti203 + 58.5HZ0, in an alumina crucible, was raised to the isothermal decomposition-temper-ature of 1370°C for five (5) hours. The temperature was then programmed cooled at 15°C per hour to 1175°C and the furnace cooled to room temperature. The ca non reactant concentra-tions were: A1=82.6 at.o, Mg=8.3 at.%, Ba=7.5 at.o, Ti=0.7 ato, Na=0.4 at. o, Nd=0.4 at. a, Cr=0.1 at. o. The X-ray purity is 990. The crystal class is hexagonal where a=5.625A and c=22.62A. After materials characterization, the compound is then ready for potential fabrications and applications, such as a solid state electrolyte, phosphor, red or tunable laser.
EXAMPLE II
General Formula L11-(x+z+d) D0.5xD0.5dJ0.33zTa1-yNbyO3 Dx = Ni, Co, Fe, Mg; Dd= Ni, Co, Cu, Zn;
J = Cr, Fe; G = F, Cl;
0<_d<_0.12; 0<-x<-1; 0<-y~l; O~z-0.4 Specific End Product Compound LlTap.65Nb0.3503 (C) The temperature of a three gram reactant mixture, con-sisting of, in mole%, 50LiF + 8.8Nb205 + 16.3Ta205 + 25H20, in an alumina crucible, was raised to the isothermal decomposi-tion-temperature of 1160°C for five (5) hours. The tempe-rature was then programmed cooled at 20°C per hour to 1000°C
and the furnace cooled to room temperature. The crystal structure is rhombohedral with a=5.1539A and c=13.81512A.
After materials characterization, the compound is then ready for potential electro-mechanical transduction fabrications and applications.
EXAMPLE III
General Formula Mgi- (x+y+Z) DZJo. 6~yRo. s~x0 D = Ni, Co, Fe, Cu, Ge, Zn;
J = Cr, Fe, Ti; R = Lanthanides 0<-x<-0.005; 0-<y<-1; 0<_z<_1 Specific End Product Compound Mg0(c) The temperature of a three gram reactant mixture, con-sisting of in mole o, 50MgF2 + 50H20, in a magnesium oxide crucible, was raised to the isothermal decomposition-tempera-ture of 1290°C for eight (8) hours. The temperature was then programmed cooled at 20°C per hour to 1050°C and the furnace cooled to room temperature. The cation reactant concentrat-ions was: Mg=100 at.%. The X-ray purity is 1000. The crystal class is cubic with a=4.213A. The product is suitable for use in infrared transmission and substrate fabrications and applications.
EXAMPLE IV
General Formula Pb2_ZDZKl_XNaxNbs-yTayOls DZ = Ba, Ca;
0<_x_<1; 0<_y_<5; 0_<z<_2 Specific End Product Compound Pb2KNbsOls ( c ) The temperature of a three gram reactant mixture; con-sisting of, in mole o, 25PbF2 + 12 . 5KF + 31. 3Nb20s + 31 . 3H20, in an alumina crucible, was raised to the isothermal decompo-sition-temperature of 1120°C for five (5) hours. The temperature was then programmed cooled at 10°C per hour to 1070°C and the furnace cooled to room temperature. The cat-ion reactant concentrations were: Pb=25.0 at.%, K=12.5 at.%, Nb=62.5 at.~. The crystal class is orthorhombic with a=17.757A, b=18.O11A, c=3.917A. The product can be used in ferroelectric-ferroelastic fabrications and applications.
EXAMPLE V
General Formula Y3_XRXAls_ ~y+W~ JyQo.7sW012 J = Cr, Ga, Ti, Fe, V, Co, Mn;
Q = Si, Ge; R = Lanthanides 0<_x<_3; 0<_y_<0.5; 0<-w-<5;
Specific End Product Compound Y2.71Nd0.29A14.999Cr0.006~12 (C) The temperature of a three gram reactant mixture, con-sisting of in mole o of, 13 . 6YF3 + 1. 5NdF3 + 14 . 9A1F3 + 5A120s + 60H20 + 150ppm Cr203, in an alumina crucible, was raised to the isothermal decomposition-temperature of 1430°C for six (5) hours. The temperature was then programmed cooled at
~sw~m 2 ) Ba2-apNal- (x-p) KxRpNbs-yTayOis 3 ) S rl- (x+2p) BaxUpRpJO. 57Nb2_yTay~g 4 ) Bal-xDXTil_ (y+o.~sZ) Jzzry03 5) KTal-(x+o.6y)NbxJy03 L11-(x+z+d) D0.5xD0.5dJ0.33zTa1-yNby~3 7 ) Mgl-(x+y+z) DzJo.6'7yRo.67x~
8 ) Mg1-xDXAl2-yJy09 9 ) Pb2-ZDZKi-xNaxNbs-yTayOls 10 ) YZ-xRXJd03 11 ) Pal2- (x+y+w) RxJyQ0.75w~3 12 ) Y3-xRxAls (y+w) JyQo.75w~12 13 ) Y3-xRxFes-yJy012 #here "U", "D", "R", "J" and "Q" are as defined hereinabove.
The UCDP manufacturing procedure, which illustrates Reactions I-IV, as already set forth, is responsible for the production of an assortment of compositions. The below examples a re given to exemplify the UCDP and the scope of the invention and are not intended to be limiting in the sense of the scope of the invention.
EXAMPLE I
General Formula Bal_(p+S+o.sx)Ro.67pDsUxMgi-yDyAllo-(Z+w)JzQo.7swW 7 R=Y, lanthanides; DS=Ca, Sr, Pb; U=K, Na;
Dy=Co, Cu, Ge, Ni, Zn; J=Cr, Ga, Ti, Mn, V, Fe, Co;
Q=Si, Ge;
0<_p<_0.6; 0.05SsS1; O~w<_7.5;
0<_x<_1.2; 0<-y<-1; 0<-z<_0.6 Specific End Product Compound Bao.9oNao.osNdo.osMg~119.siaCro.oo6Tio.oaCm (c) (New Composition) The temperature of a three gram reactant mixture, con-sisting of, in mole %, 3.12BaFz + 0.02NaF + 0.02NdF3 + 3.5MgFz + 20.6A1F3 + 6.9AIz03 + O.O1Ti203 + 58.5HZ0, in an alumina crucible, was raised to the isothermal decomposition-temper-ature of 1370°C for five (5) hours. The temperature was then programmed cooled at 15°C per hour to 1175°C and the furnace cooled to room temperature. The ca non reactant concentra-tions were: A1=82.6 at.o, Mg=8.3 at.%, Ba=7.5 at.o, Ti=0.7 ato, Na=0.4 at. o, Nd=0.4 at. a, Cr=0.1 at. o. The X-ray purity is 990. The crystal class is hexagonal where a=5.625A and c=22.62A. After materials characterization, the compound is then ready for potential fabrications and applications, such as a solid state electrolyte, phosphor, red or tunable laser.
EXAMPLE II
General Formula L11-(x+z+d) D0.5xD0.5dJ0.33zTa1-yNbyO3 Dx = Ni, Co, Fe, Mg; Dd= Ni, Co, Cu, Zn;
J = Cr, Fe; G = F, Cl;
0<_d<_0.12; 0<-x<-1; 0<-y~l; O~z-0.4 Specific End Product Compound LlTap.65Nb0.3503 (C) The temperature of a three gram reactant mixture, con-sisting of, in mole%, 50LiF + 8.8Nb205 + 16.3Ta205 + 25H20, in an alumina crucible, was raised to the isothermal decomposi-tion-temperature of 1160°C for five (5) hours. The tempe-rature was then programmed cooled at 20°C per hour to 1000°C
and the furnace cooled to room temperature. The crystal structure is rhombohedral with a=5.1539A and c=13.81512A.
After materials characterization, the compound is then ready for potential electro-mechanical transduction fabrications and applications.
EXAMPLE III
General Formula Mgi- (x+y+Z) DZJo. 6~yRo. s~x0 D = Ni, Co, Fe, Cu, Ge, Zn;
J = Cr, Fe, Ti; R = Lanthanides 0<-x<-0.005; 0-<y<-1; 0<_z<_1 Specific End Product Compound Mg0(c) The temperature of a three gram reactant mixture, con-sisting of in mole o, 50MgF2 + 50H20, in a magnesium oxide crucible, was raised to the isothermal decomposition-tempera-ture of 1290°C for eight (8) hours. The temperature was then programmed cooled at 20°C per hour to 1050°C and the furnace cooled to room temperature. The cation reactant concentrat-ions was: Mg=100 at.%. The X-ray purity is 1000. The crystal class is cubic with a=4.213A. The product is suitable for use in infrared transmission and substrate fabrications and applications.
EXAMPLE IV
General Formula Pb2_ZDZKl_XNaxNbs-yTayOls DZ = Ba, Ca;
0<_x_<1; 0<_y_<5; 0_<z<_2 Specific End Product Compound Pb2KNbsOls ( c ) The temperature of a three gram reactant mixture; con-sisting of, in mole o, 25PbF2 + 12 . 5KF + 31. 3Nb20s + 31 . 3H20, in an alumina crucible, was raised to the isothermal decompo-sition-temperature of 1120°C for five (5) hours. The temperature was then programmed cooled at 10°C per hour to 1070°C and the furnace cooled to room temperature. The cat-ion reactant concentrations were: Pb=25.0 at.%, K=12.5 at.%, Nb=62.5 at.~. The crystal class is orthorhombic with a=17.757A, b=18.O11A, c=3.917A. The product can be used in ferroelectric-ferroelastic fabrications and applications.
EXAMPLE V
General Formula Y3_XRXAls_ ~y+W~ JyQo.7sW012 J = Cr, Ga, Ti, Fe, V, Co, Mn;
Q = Si, Ge; R = Lanthanides 0<_x<_3; 0<_y_<0.5; 0<-w-<5;
Specific End Product Compound Y2.71Nd0.29A14.999Cr0.006~12 (C) The temperature of a three gram reactant mixture, con-sisting of in mole o of, 13 . 6YF3 + 1. 5NdF3 + 14 . 9A1F3 + 5A120s + 60H20 + 150ppm Cr203, in an alumina crucible, was raised to the isothermal decomposition-temperature of 1430°C for six (5) hours. The temperature was then programmed cooled at
15°C per hour to 1150°C and the furnace cooled to room tem-perature. The cation reactant concentrations were: Y=33.87 at.%, Nd=3.63 at.~, A1=62.42 at.$, Cr=0.08 at.$. The X-ray purity is 99%. The crystal class is cubic where a=12.009.x.
The product is suitable for use in doubly doped laser fabri-cations.
While the embodiments described herein are illustrative of the principles of this UCDP invention, various modifica-tions and advantages may be achieved by those skilled in the art without departing from the scope and the spirit of this invention; as defined by the following claims.
_ ~ ~
The product is suitable for use in doubly doped laser fabri-cations.
While the embodiments described herein are illustrative of the principles of this UCDP invention, various modifica-tions and advantages may be achieved by those skilled in the art without departing from the scope and the spirit of this invention; as defined by the following claims.
_ ~ ~
Claims (2)
1. A process for producing a refractory oxide which com-prises (a) reacting and dispersal-blending liquid water with at least one metal oxide reactant and a hydrogen halide composition, to produce a cationically-homogeneous nanostruc-tured colloidal mixture; (b) heating the colloidal mixture to produce a solid state metal hydroxyhalide; (c) further heating the metal hydroxyhalide to a higher temperature at which it chemically decomposes, by heat alone, into a cat-ionically-homogeneous nanostructured solid state metal oxy-halide; and performing one of the following heating steps:
(i) heating the metal oxyhalide to a solid state de-composition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; (ii) heating the metal oxy-halide to a molten state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide;
(iii) heating the metal oxyhalide to a vapor state decomposi-tion-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
(i) heating the metal oxyhalide to a solid state de-composition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; (ii) heating the metal oxy-halide to a molten state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide;
(iii) heating the metal oxyhalide to a vapor state decomposi-tion-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
2. A process according to claim 1, wherein the reactants, Y2O3, a hydrogen fluoride composition and liquid water, are mixed and heated to the Y2O3F3 3- decomposition-temperature of ca.1550°C to produce transparent Y2O3 crystals.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US84321892A | 1992-02-28 | 1992-02-28 | |
| US07/843,218 | 1992-02-28 | ||
| CA002131326A CA2131326C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002131326A Division CA2131326C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
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|---|---|
| CA2455428A1 CA2455428A1 (en) | 1993-09-16 |
| CA2455428C true CA2455428C (en) | 2004-10-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| CA002131326A Expired - Lifetime CA2131326C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
| CA002455428A Expired - Lifetime CA2455428C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
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| CA002131326A Expired - Lifetime CA2131326C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
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| WO (1) | WO1993017959A1 (en) |
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| IT1277836B1 (en) * | 1995-03-13 | 1997-11-12 | Colorobbia Italiana Spa | ALUMINATES OF Yttrium AND / OR RARE EARTH WITH PEROVSKITIC STRUCTURE, THEIR PREPARATION AND USE AS PIGMENTS |
| DK172530B1 (en) | 1995-11-10 | 1998-11-23 | Leo Pharm Prod Ltd | Additive product for drinking water and animal feed and method of addition |
| KR100290437B1 (en) * | 1998-10-07 | 2001-09-22 | 박찬구 | Preparation of Niodymium Halogen Complexes Suitable for Continuous 1,3-Butadiene Polymerization |
| US6316377B1 (en) * | 1999-09-10 | 2001-11-13 | Battelle Memorial Institute | Rare earth oxide fluoride nanoparticles and hydrothermal method for forming nanoparticles |
| CN105905930B (en) * | 2016-04-12 | 2017-10-20 | 广西华银铝业有限公司 | Sodium aluminate solution refines filter aid and prepared and filter cake Application way in alumina producing |
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| US2942944A (en) * | 1958-11-26 | 1960-06-28 | Harley A Wilhelm | Process of preparing zirconium oxychloride |
| US3148943A (en) * | 1962-12-26 | 1964-09-15 | M & T Chemicals Inc | Novel process for preparing antimony oxychloride |
| US3370017A (en) * | 1963-07-30 | 1968-02-20 | Du Pont | Microcrystalline corundum powder, sols thereof, and processes for preparing both |
| US3607770A (en) * | 1968-10-23 | 1971-09-21 | Gen Electric | Gaseous reaction process for the production of rare earth oxyhalide and oxide luminescent materials |
| US4271131A (en) * | 1979-04-11 | 1981-06-02 | Foote Mineral Company | Production of highly pure lithium chloride from impure brines |
-
1993
- 1993-03-01 CA CA002131326A patent/CA2131326C/en not_active Expired - Lifetime
- 1993-03-01 WO PCT/US1993/001846 patent/WO1993017959A1/en active Application Filing
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| WO1993017959A1 (en) | 1993-09-16 |
| CA2455428A1 (en) | 1993-09-16 |
| CA2131326A1 (en) | 1993-09-16 |
| CA2131326C (en) | 2005-02-15 |
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