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A gas detection device comprising a measuring circuit, said measuring surface comprising a substrate, a resistance heater bonded to said substrate and a coating, said coating comprising SnO2 nanoparticles doped with In2O3 nanoparticles and Pd oxide, said Pd oxide being formed from a solution of a Pd

A gas detection device comprising a measuring circuit, said measuring surface comprising a substrate, a resistance heater bonded to said substrate and a coating, said coating comprising SnO2 nanoparticles doped with In2O3 nanoparticles and Pd oxide, said Pd oxide being formed from a solution of a Pd salt, such as PdCl2. The SnO2 nanocrystals have a specific surface of at least about 50 m2/g, a mean particle size of between about 5 nm and about 20 nm, and the contact points between individual nanoparticles of SnO2 and In2O3 and the associated Pd oxide are less than about 100 Å. The Pd salt solution is a solution of a palladium chloride in a dilute acid solution, such as HCl. The palladium salt to an oxide of palladium at an elevated temperature, as for example, by calcining said oxide of palladium. The palladium Marked Copy oxide is in the form of a coating on nanoparticles of SnO2 and In2O3.

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1. A composition for use in producing a gas sensitive material with high efficiency and fast response, said composition comprising: —SnO2— nanocrystals doped with —In2O3— and a solution of a salt of a platinum group metal, wherein said salt of a platinum group metal is a Pd salt selected from the gr

1. A composition for use in producing a gas sensitive material with high efficiency and fast response, said composition comprising: —SnO2— nanocrystals doped with —In2O3— and a solution of a salt of a platinum group metal, wherein said salt of a platinum group metal is a Pd salt selected from the group comprising (ethylenediamine)palladium(II) chloride Pd(H2NCH2CH2NH2)Cl2, ammonium tetrachloropalladate(II) (NH4)2PdCl4, Bis(acetonitrile)dichloropalladium(II) PdCl2.(CH3CN)2, Bis(benzonitrile)palladium(II) chloride (C6H5CN)2PdCl2, (2-methylallyl)palladium(II) chloride dimer [(C4H7)PdCl]2, and combinations thereof. 2. The composition of claim 1, further comprising at least one of a surfactant and a blowing agent. 3. A composition for use in producing a gas sensitive material with high efficiency and fast response, said composition comprising: SnO2 nanocrystals doped with In2O3 and a solution of a salt of a platinum group metal wherein said salt is PdCl2 in an HCl solution. 4. The composition of claim 3, further comprising a surfactant and a blowing agent, wherein the surfactant comprises between about 8% to about 20% of the mixture by weight and the blowing agent comprises between about 3% and about 6% of the mixture by weight. 5. The composition of claim 4, wherein the surfactant comprises about 15% of the mixture by weight and the blowing agent comprises about 5% of the mixture by weight. 6. A gas sensitive material comprising SnO2 nanoparticles doped with In2O3 and an oxide of a platinum group metal, wherein said SnO2 nanoparticles have a specific surface greater than 10 m2/g and wherein said SnO2 nanoparticles have a mean particle size of between about 5 nm and about 20 nm. 7. The gas sensitive material of claim 6, wherein said oxide of a platinum group is the reaction product of nanoparticles SnO2, In2O3, and an aqueous HCl solution of a Pd salt converted to Pd oxide. 8. The gas sensitive material of claim 6, wherein said SnO2 nanoparticles have a specific surface of at least about 20 m2/g. 9. The gas sensitive material of claim 8, wherein said SnO2 nanoparticles have a specific surface of at least about 50 m2/g. 10. The gas sensitive material of claim 6, wherein said gas is hydrogen. 11. The gas sensitive material of claim 6, wherein the oxide of the platinum group metal comprises between about 2% and about 5% of the weight of the SnO2 nanoparticles and the In2O3 comprises between about 3% and about 12% of the weight of the SnO2 particles. 12. A method of producing a gas sensitive material comprising the steps of blending a Pd salt solution with nanometal oxide particles to enable the Pd to associate with the oxide nanoparticles, and converting said Pd salt to a dispersed Pd oxide, wherein said Pd salt solution is a solution of a palladium salt that dissolves in dilute aqueous HCl and further comprising the step of converting said palladium salt to an oxide of palladium at a temperature below about 600 deg. C., and further comprising collecting calcined particles that pass through a 100 mesh sieve. 13. The method of claim 12, wherein said Pd salt is PdCl2. 14. The method of claim 12, wherein said nanometal oxide particles comprise SnO2 and In2O3. 15. The method of claim 12, comprising the step of adding at least one of a surfactant and a blowing agent and forming a multi-component paste composition. 16. The method of claim 15, wherein the surfactant is stearic acid. 17. The method of claim 15, wherein the surfactant is a compound that completely decomposes to a gas product or products and is removed at an elevated temperature from the paste composition during the formation of the gas sensitive material. 18. The method of claim 17, further comprising the step of forming the oxide nanoparticles and dispersed Pd oxide into a film and heating or calcining the film to a temperature sufficient to decompose organic components that are present in the film. 19. The method of claim 15, wherein the surfactant is a carbonic acid with long carbonic chains, or a non-ionic surfactant. 20. The method of claim 15, wherein the blowing agent is selected from group comprising, ammonium carbonate, azo-compounds, and ammonium chloride. 21. The method of claim 15, wherein the blowing agent is a compound that decomposes to a gas form, and wherein said gas is at least one of CO2, NH3, and N2. 22. The method of claim 12, wherein said Pd salt solution is a solution of a salt selected from the group comprising (ethylenediamine)palladium(II) chloride Pd(H2NCH2CH2NH2)Cl2, ammonium tetrachloropalladate(II) (NH4)2PdCl4, Bis(acetonitrile)dichloropalladium(II) PdCl2.(CH3CN)2, Bis(benzonitrile)palladium(II) chloride (C6H5CN)2PdCl2, (2-methylallyl)palladium(II) chloride dimer [(C4H7)PdCl]2, and combinations thereof. 23. The method of claim 12, wherein said Pd salt solution is a solution of PdCl2, and wherein the step of converting said palladium salt to an oxide of palladium is at a temperature below about 500 deg. C. 24. The method of claim 23, wherein nanometal oxide particles comprise SnO2 and In2O3. 25. The method of claim 24, wherein the SnO2 nanocrystals have a specific surface of at least about 20 m2/g and wherein the SnO2 nanocrystals have a specific surface of at least about 50 m2/g. 26. The method of claim 24, wherein the SnO2 particles have a mean particle size of between about 5 nm and about 20 nm. 27. The method of claim 12, further comprising forming a gas sensitive material, wherein the composition of the resultant gas sensitive material comprises, an oxide of the platinum group metal comprising between about 2% and about 5% of the weight of the SnO2 and the In2O3 nanometal oxide particles comprising between about 3% and about 12% of the weight of the SnO2 nanocrystals. 28. The method of claim 12, further comprising the step of depositing the gas sensitive material on a substrate, incorporating said gas sensitive material in a measuring circuit, and wherein said substrate is in communication with a heat source. 29. The method of claim 12, further comprising the step of applying said gas sensitive material to a substrate by spraying or silk screening. 30. The method of claim 12, further comprising producing Pd coating on the nanoparticles, said coating being on the order of an angstrom thick. 31. A gas detection device comprising a measuring circuit, said measuring surface comprising a substrate, a resistance heater bonded to said substrate and a coating, said coating comprising SnO2 nanoparticles doped with In2O3 nanoparticles and Pd oxide, said Pd oxide being formed from an acidic solution of PdCl2, and wherein the contact points between individual nanoparticles of SnO2 and In2O3 and the associated Pd oxide are less than about 100 Å. 32. The gas detection device of claim 31, said SnO2 nanocrystals having a specific surface of at least about 50 m2/g, a mean particle size of between about 5 nm and about 20 nm. 33. A composition for use in producing a gas sensitive material with high efficiency and fast response, said composition comprising: SnO2 nanocrystals doped with In2O3 and a solution of a salt of a platinum group metal,wherein said salt of a platinum group metal is a Pd salt selected from the group comprising PdCl2, (ethylenediamine)palladium(II) chloride Pd(H2NCH2CH2NH2)Cl2, ammonium tetrachloropalladate(II) (NH4)2PdCl4, Bis(acetonitrile)dichloropalladium(II) PdCl2.(CH3CN)2, Bis(benzonitrile)palladium(II) chloride (C6H5CN)2PdCl2, (2-methylallyl)palladium(II) chloride dimer [(C4H7)PdCl]2, and combinations thereof,wherein said salt of Pd is PdCl2 in an aqueous solution,further comprising a surfactant and a blowing agent, andwherein the surfactant comprises between about 8% to about 20% of the mixture by weight and the blowing agent comprises between about 3% and about 6% of the mixture by weight. 34. The composition of claim 33, wherein the surfactant comprises about 15% of the mixture by weight and the blowing agent comprises about 5% of the mixture by weight. 35. A gas sensitive material comprising SnO2 nanoparticles doped with In2O3 and an oxide of a platinum group metal, wherein said SnO2 particles have a specific surface greater than 10 m2/g, wherein the contact points between individual nanoparticles of SnO2 and In2O3, and the associated Pd oxide are less than about 100 Å. 36. A method of producing a gas sensitive material comprising the steps of blending a Pd salt solution with nanometal oxide particles to enable the Pd to associate with the oxide nanoparticles, and converting said Pd salt to a dispersed Pd oxide, further comprising the step of adding a surfactant and processing to produce a gas sensitive material having a molecular spacing of up to about 100 Å between the contacting nanoparticles. 37. A method of producing a gas sensitive material comprising the steps of blending a Pd salt solution with nanometal oxide particles to enable the Pd to associate with the oxide nanoparticles, and converting said Pd salt to a dispersed Pd oxide: wherein said Pd salt solution is a solution of a palladium salt that readily dissolves in dilute aqueous HCl and further comprising the step of converting said palladium salt to an oxide of palladium at a temperature below about 600 deg. C., without leaving significant residues;wherein nanometal oxide powders comprise SnO2 and In2O3;wherein the step of blending a Pd salt solution with the nanometal oxide powders comprises coating or impregnating said SnO2 and In2O3 nanopowders with PdCl2, and then calcining to remove any remaining chlorine components;wherein said calcining is at a calcining temperature below about 500 deg. C. and further comprising collecting calcined powders that can pass through a 100 mesh sieve. 38. A method of producing a gas sensitive material comprising the steps of: blending a Pd salt solution with nanometal oxide particles to enable the Pd to associate with the oxide nanoparticles, and converting said Pd salt to a dispersed Pd oxide;adding a surfactant and forming a multi-component paste composition, said step of adding surfactant being prior to the step of calcining;removing said surfactant in the calcining step, leaving the contact distances necessary to increase the number and efficacy of the active centers;and wherein a Pd coating is produced on the nanoparticles, said coating being on the order of an angstrom thick. 39. A method of producing a gas sensitive material comprising the steps of blending a Pd salt solution with nanometal oxide particles to enable the Pd to associate with the oxide nanoparticles, and converting said Pd salt to a dispersed Pd oxide; the step of adding a surfactant and a blowing agent and forming a multi-component paste composition,said step of adding a surfactant being prior to calcining;removing said surfactant in the calcining step, leaving the contact distances necessary to increase the number and efficacy of the active centers;wherein said nanometal oxide particles comprise SnO2 and In2O3 and the surfactant comprises between about 8% to about 20% of the SnO2, In2O3, PdCl2 mixture by weight and the blowing agent comprises between about 3% and about 6% of the mixture by weight. 40. The method of claim 39, wherein the blowing agent is selected from group comprising, ammonium carbonate, azo-compounds, and ammonium chloride. 41. The method of claim 39, wherein the blowing agent is a compound that decomposes to a gas form, and wherein said gas is at least one of CO2, NH3, and N2. 42. A gas detection device comprising a measuring circuit, said measuring circuit comprising a substrate, a resistance heater bonded to said substrate and a coating, said coating comprising SnO2 nanoparticles doped with In2O3 nanoparticles and Pd oxide, said Pd oxide being formed from a solution of PdCl2, said SnO2 nanocrystals having a specific surface of at least about 50 m2/g, a mean particle size of between about 5 nm and about 20 nm, and the contact points between individual nanoparticles of SnO2 and In2O3 and the associated Pd oxide are less than about 100 Å.