Provided is an electrode catalyst in which the contents of chlorine (Cl) species and bromine (Br) species are reduced to a predetermined level or lower, capable of exhibiting sufficient catalyst performance. The electrode catalyst has a core-shell structure including a support, a core part formed on the support and a shell part formed to cover at least a part of the surface of the core part. A concentration of bromine (Br) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 400 ppm or less, and a concentration of chlorine (Cl) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 900 ppm or less.

Provided is an electrode catalyst in which the contents of chlorine (Cl) species and bromine (Br) species are reduced to a predetermined level or lower, capable of exhibiting sufficient catalyst performance. The electrode catalyst has a core-shell structure including a support, a core part formed on the support and a shell part formed to cover at least a part of the surface of the core part. A concentration of bromine (Br) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 400 ppm or less, and a concentration of chlorine (Cl) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 900 ppm or less.

The present invention relates to a process for the preparation of ruthenium(III) chloride (RuCl.sub.3) as well to a process for the purification of ruthenium(III) chloride (RuCl.sub.3) and a use of the process for the preparation or the purification of ruthenium(III) chloride (RuCl.sub.3).

The present invention relates to a semiconductor device comprising a semiconducting material, wherein the semiconducting material comprises a halometallate compound comprising: (a) cesium; (b) palladium; and (c) one or more halide anions [X]. The invention also relates to a layer comprising the semiconducting material. The invention further relates to a process for producing a halometallate compound of formula (IV): [A].sub.2[M.sup.IV][X].sub.6, which process uses a H[X] and a compound comprising a sulfoxide group.

Process for the production of high purity iridium(III) chloride hydrate, comprising the steps of: (1) providing at least one material selected from the group consisting of solid H.sub.2[IrCl.sub.6] hydrate, aqueous, at least 1 wt. % H.sub.2[IrCl.sub.6] solution, and solid IrCl.sub.4 hydrate; (2) adding, to the at least one material provided in step (1), at least one monohydroxy compound selected from the group consisting of monohydroxy compounds that are miscible with water at any ratio, primary monoalcohols comprising 4 to 6 carbon atoms, and secondary monoalcohols comprising 4 to 6 carbon atoms at a molar ratio of Ir(IV):monohydroxy compound=1:0.6 to 1000, and allowing to react for 0.2 to 48 hours in a temperature range from 20 to 120° C., followed by removing volatile components from the reaction mixture thus formed.

Provided is a method of making an inorganic platinum compound. The method includes the steps of: Step (A): providing a platinum material and a halogen-containing oxidizing agent; and Step (B): treating the platinum material with the halogen-containing oxidizing agent in a hydrochloric acid aqueous solution to obtain the inorganic platinum compound, including chloroplatinic acid or chloroplatinate salt; wherein the halogen-containing oxidizing agent excludes chlorine gas. The method of making an inorganic platinum compound is simple, safe, time-effective, cost-effective, and environment-friendly, and has the advantage of high yield.

Provided is a method of making an inorganic platinum compound. The method includes the steps of: Step (A): providing a platinum material and a halogen-containing oxidizing agent; and Step (B): treating the platinum material with the halogen-containing oxidizing agent in a hydrochloric acid aqueous solution to obtain the inorganic platinum compound, including chloroplatinic acid or chloroplatinate salt; wherein the halogen-containing oxidizing agent excludes chlorine gas. The method of making an inorganic platinum compound is simple, safe, time-effective, cost-effective, and environment-friendly, and has the advantage of high yield.

The disclosure provides a method of producing a platinum colloid comprising reducing platinum ions by the use of a platinum ion solution, water, a nonionic surfactant, a pH adjusting agent, and a reducing agent, wherein the platinum ion solution contains platinum at a concentration of 20 w/v %, the nonionic surfactant is polysorbate 80, the pH adjusting agent is an alkaline metal salt, the reducing agent is a lower alcohol, the volume of the water is from 600 to 660 times that of the platinum ion solution, the volume of the nonionic surfactant is from 0.20 to 0.30 times that of the platinum ion solution, the volume of the pH adjusting agent as a 5 w/v % aqueous solution is from 10 to 30 times that of the platinum ion solution, and the volume of the reducing agent is from 27 to 37 times that of the platinum ion solution,
as well as the platinum colloid produced by the method.

The present invention relates to a semiconductor device comprising a semiconducting material, wherein the semiconducting material comprises a halometallate compound comprising: (a) cesium; (b) palladium; and (c) one or more halide anions [X]. The invention also relates to a layer comprising the semiconducting material. The invention further relates to a process for producing a halometallate compound of formula (IV): [A].sub.2[M.sup.IV][X].sub.6, which process uses a H[X] and a compound comprising a sulfoxide group.

A method for recovery of platinum group metals from a spent catalyst is described. The method includes crushing the spent catalyst to obtain a catalyst particulate material including particles having a predetermined grain size. The method includes subjecting the catalyst particulate material to a chlorinating treatment in the reaction zone at a predetermined temperature for a predetermined time period by putting the catalyst particulate material in contact with the chlorine containing gas. The method also includes applying an electromagnetic field to the chlorine-containing gas in the reaction zone to provide ionization of chlorine; thereby to cause a chemical reaction between platinum group metals and chlorine ions and provide a volatile platinum group metal-containing chloride product in the reaction zone. Following this, the volatile platinum group metal-containing chloride product is cooled to convert the product into solid phase platinum group metal-containing materials.