A method of forming a silver catalyst layer in chemical plating includes providing a substrate; applying a silver-containing solution onto the substrate; and applying energy of activation to the silver-containing solution to form a silver catalyst layer over the substrate. The silver-containing solution includes silver ions, a diamine compound, a carboxylic acid compound, and a solvent. In addition, the substrate having the silver catalyst layer thereon can be immersed into a chemical plating solution to form a metal layer over the silver catalyst layer.

A method of forming a silver catalyst layer in chemical plating includes providing a substrate; applying a silver-containing solution onto the substrate; and applying energy of activation to the silver-containing solution to form a silver catalyst layer over the substrate. The silver-containing solution includes silver ions, a diamine compound, a carboxylic acid compound, and a solvent. In addition, the substrate having the silver catalyst layer thereon can be immersed into a chemical plating solution to form a metal layer over the silver catalyst layer.

A precursor mixture for producing a porous body, wherein the precursor mixture comprises: (i) at least one milled alpha alumina powder having a particle size of 0.1 to 6 microns, (ii) non-silicate powder that functions as a binder of the alpha alumina powders, and (iii) at least one burnout material having a particle size of 1-10 microns and a decomposition temperature of less than 550° C., with the proviso that a burnout material having a decomposition temperature of 550° C. or greater is excluded from the precursor mixture.

A precursor mixture for producing a porous body, wherein the precursor mixture comprises: (i) at least one milled alpha alumina powder having a particle size of 0.1 to 6 microns, (ii) non-silicate powder that functions as a binder of the alpha alumina powders, and (iii) at least one burnout material having a particle size of 1-10 microns and a decomposition temperature of less than 550° C., with the proviso that a burnout material having a decomposition temperature of 550° C. or greater is excluded from the precursor mixture.

Plasmonic diamond films are provided. In an embodiment, a plasmonic diamond film comprises a plurality of plasmonic nanoparticles encapsulated by diamond and distributed on an underlying surface of diamond. Methods of forming the plasmonic diamond films are also provided.

Plasmonic diamond films are provided. In an embodiment, a plasmonic diamond film comprises a plurality of plasmonic nanoparticles encapsulated by diamond and distributed on an underlying surface of diamond. Methods of forming the plasmonic diamond films are also provided.

A porous alpha-alumina catalyst support is prepared by (i) preparing a precursor material comprising a boehmitic-derived alumina having a pore volume of at least 0.6 mL/g, wherein the boehmitic-derived alumina is obtained by thermal decomposition of a boehmitic starting material and the boehmitic starting material consists predominantly of block-shaped crystals, and optionally an inorganic bond material; (ii) forming the precursor material into shaped bodies; (iii) calcining the shaped bodies to obtain the porous alpha-alumina catalyst support. The support structure has a high overall pore volume, while keeping its surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The support is useful for a catalyst for producing ethylene oxide by gas-phase oxidation of ethylene.

A porous alpha-alumina catalyst support is prepared by (i) preparing a precursor material comprising a boehmitic-derived alumina having a pore volume of at least 0.6 mL/g, wherein the boehmitic-derived alumina is obtained by thermal decomposition of a boehmitic starting material and the boehmitic starting material consists predominantly of block-shaped crystals, and optionally an inorganic bond material; (ii) forming the precursor material into shaped bodies; (iii) calcining the shaped bodies to obtain the porous alpha-alumina catalyst support. The support structure has a high overall pore volume, while keeping its surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The support is useful for a catalyst for producing ethylene oxide by gas-phase oxidation of ethylene.

A process for producing a porous alpha-alumina catalyst support, comprising i) preparing a precursor material comprising, based on inorganic solids content, at least 50 wt.-% of a transition alumina having a loose bulk density of at most 600 g/L, a pore volume of at least 0.6 mL/g and a median pore diameter of at least 15 nm; and at most 30 wt.-% of an alumina hydrate; ii) forming the precursor material into shaped bodies; and iii) calcining the shaped bodies to obtain the porous alpha-alumina catalyst support. The catalyst support has a high overall pore volume, thus allowing for impregnation with a high amount of silver, while keeping its surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The invention further relates to a shaped catalyst body for producing ethylene oxide by gas-phase oxidation of ethylene, comprising at least 15 wt.-% of silver, relative to the total weight of the catalyst, deposited on a porous alpha-alumina catalyst support obtained in the process described above. The invention also relates to a process for preparing a shaped catalyst body as described above comprising impregnating a porous alpha-alumina catalyst support obtained in the process described above with a silver impregnation solution, preferably under reduced pressure; and optionally subjecting the impregnated porous alumina support to drying; and b) subjecting the impregnated porous alpha-alumina support to a heat treatment; wherein steps a) and b) are optionally repeated. The invention further relates to a process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising reacting ethylene and oxygen in the presence of a shaped catalyst body as described above.

A process for producing a porous alpha-alumina catalyst support, comprising i) preparing a precursor material comprising, based on inorganic solids content, at least 50 wt.-% of a transition alumina having a loose bulk density of at most 600 g/L, a pore volume of at least 0.6 mL/g and a median pore diameter of at least 15 nm; and at most 30 wt.-% of an alumina hydrate; ii) forming the precursor material into shaped bodies; and iii) calcining the shaped bodies to obtain the porous alpha-alumina catalyst support. The catalyst support has a high overall pore volume, thus allowing for impregnation with a high amount of silver, while keeping its surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The invention further relates to a shaped catalyst body for producing ethylene oxide by gas-phase oxidation of ethylene, comprising at least 15 wt.-% of silver, relative to the total weight of the catalyst, deposited on a porous alpha-alumina catalyst support obtained in the process described above. The invention also relates to a process for preparing a shaped catalyst body as described above comprising impregnating a porous alpha-alumina catalyst support obtained in the process described above with a silver impregnation solution, preferably under reduced pressure; and optionally subjecting the impregnated porous alumina support to drying; and b) subjecting the impregnated porous alpha-alumina support to a heat treatment; wherein steps a) and b) are optionally repeated. The invention further relates to a process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising reacting ethylene and oxygen in the presence of a shaped catalyst body as described above.