The present invention relates to a catalyst for producing carbon nanotubes, a method for preparing the catalyst, and a method for producing carbon nanotubes using the catalyst which includes a support, and an active layer formed on a surface of the support, wherein the active layer contains CoO and Co.sub.3O.sub.4, and has, through XRD pattern measurement, one peak at 2?=35? to 38?, and one peak at 2?=41? to 44?, and a proportion of CoO among the CoO and Co.sub.3O.sub.4 is 55 at % or more. The catalyst according to the present invention can efficiently synthesize low-diameter carbon nanotubes.

The present invention relates to a method for preparing a carbon nanotube-producing catalyst using chemical vapor deposition method. Using the above preparation method, a uniform and thin coating layer can be formed even on the surface of a support having a high-specific-surface-area having a 3D structure, and high-quality and low-diameter carbon nanotubes can be produced using the catalyst prepared through this method.

The present invention relates to a method for preparing a carbon nanotube-producing catalyst using chemical vapor deposition method. Using the above preparation method, a uniform and thin coating layer can be formed even on the surface of a support having a high-specific-surface-area having a 3D structure, and high-quality and low-diameter carbon nanotubes can be produced using the catalyst prepared through this method.

Methods for preparing a layered metal nanocomposite and a layered metal nanocomposite. The method includes mixing a magnesium salt and a aluminum salt to form a Mg.sup.2+/Al.sup.3+ solution. The Mg/Al has a molar ratio of between 0.5:1 to 6:1. Then a diamondoid compound is added to the Mg.sup.2+/Al.sup.3+ solution to form a reactant mixture. The diamondoid compound has at least one carboxylic acid moiety. The reactant mixture is heated at a reaction temperature for a reaction time to form a Mg/Al-diamondoid intercalated layered double hydroxide. The Mg/Al-diamondoid intercalated layered double hydroxide is thermally decomposed under a reducing atmosphere for a decomposition time at a decomposition temperature to form the layered metal nanocomposite.

An autothermal reforming catalytic structure for generating hydrogen gas from liquid hydrocarbons, steam and an oxygen source. The autothermal reforming catalytic structure includes a support structure and metal particles dispersed homogenously throughout the support structure.

An autothermal reforming catalytic structure for generating hydrogen gas from liquid hydrocarbons, steam and an oxygen source. The autothermal reforming catalytic structure includes a support structure and metal particles dispersed homogenously throughout the support structure.

A method of making silica-layered double hydroxide microspheres having the formula I: (i) wherein, M.sup.z+ and M.sup.y+ are two different charged metal cations; z=1 or 2; y=3 or 4; 0<x<0.9; b is 0 to 10; c is 0 to 10; P>0, q>0, X.sup.n is an anion; with n>0 a=z(1x)+xy2; and the AMO-solvent is an 100% aqueous miscible organic solvent; comprises the steps: (a) contacting silica microspheres and a metal ion containing solution containing metal ions M.sup.z+ and M.sup.y+ in the presence of a base and an anion solution; (b) collecting the product; and (c) optionally treating the product with AMO-solvent and recovering the solvent treated material to obtain the silica-layered double hydroxide microspheres. Preferably, M in the formula I is Li, Mg, Ni or Ca. Preferably, M in formula I is Al. The invention further provides silica-layered double hydroxide microspheres having the formula I. The silica-layered double hydroxide microspheres may be used as catalysts and/or catalyst supports.

(SiO.sub.2).sub.p@{[M.sup.z+.sub.(1x)M.sup.y+.sub.x(OH).sub.2].sup.a+(X.sup.n).sub.a/n.bH.sub.2O.c(AMO-solvent)}.sub.q(I)

A method of making silica-layered double hydroxide microspheres having the formula I: (i) wherein, M.sup.z+ and M.sup.y+ are two different charged metal cations; z=1 or 2; y=3 or 4; 0<x<0.9; b is 0 to 10; c is 0 to 10; P>0, q>0, X.sup.n is an anion; with n>0 a=z(1x)+xy2; and the AMO-solvent is an 100% aqueous miscible organic solvent; comprises the steps: (a) contacting silica microspheres and a metal ion containing solution containing metal ions M.sup.z+ and M.sup.y+ in the presence of a base and an anion solution; (b) collecting the product; and (c) optionally treating the product with AMO-solvent and recovering the solvent treated material to obtain the silica-layered double hydroxide microspheres. Preferably, M in the formula I is Li, Mg, Ni or Ca. Preferably, M in formula I is Al. The invention further provides silica-layered double hydroxide microspheres having the formula I. The silica-layered double hydroxide microspheres may be used as catalysts and/or catalyst supports.

(SiO.sub.2).sub.p@{[M.sup.z+.sub.(1x)M.sup.y+.sub.x(OH).sub.2].sup.a+(X.sup.n).sub.a/n.bH.sub.2O.c(AMO-solvent)}.sub.q(I)

An autothermal reforming catalytic structure for generating hydrogen gas from liquid hydrocarbons, steam and an oxygen source. The autothermal reforming catalytic structure includes a support structure and nanosized mixed metal oxide particles dispersed homogenously throughout the support structure.

An autothermal reforming catalytic structure for generating hydrogen gas from liquid hydrocarbons, steam and an oxygen source. The autothermal reforming catalytic structure includes a support structure and nanosized mixed metal oxide particles dispersed homogenously throughout the support structure.