Method for producing a hierarchically structured porous precious metal catalyst in powder form and use of said precious metal catalyst

Abstract

The invention relates to a method for producing a hierarchically structured porous powder of an iridium and / or ruthenium compound, comprising the following steps: (i.) providing a solution which comprises a precious metal precursor, a soft template and a first solvent, the noble metal precursor comprising an iridium and / or ruthenium salt and the soft template being an amphiphilic polymer; (ii.) providing a hard template, the hard template being a colloidal particle; (iii.) mixing the solution (i.) and the hard template (ii.) and drying the mixture; (iv.) thermally treating the solid from (iii.) at a temperature T1, the temperature T1 being higher than the glass transition temperature of the hard template; (v.) adding a second solvent to the solid from (iv.) and subsequently removing the solvent; and (vi.) thermally treating (calcining) the solid from (v.) at a maximum temperature T2 to form the powder of an iridium and / or ruthenium compound, wherein the soft template and the hard template are decomposed by steps (iv.) to (vi.) and the powder of an iridium and / or ruthenium compound is formed, said powder having macropores with pore walls structured by mesopores. The invention further relates to a powder which can be produced by means of the method and to the use of said powder as a catalyst.

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