low chlorine platinum and platinum alloy powders with increased specific surface area and process for the preparation thereof using a nitrate salt melt

Platinum or platinum alloy powder for use as a catalyst in fuel cells or chemical reactions combines a BET specific surface area above 40m/g with a chlorine content below 100ppm. An Independent claim is also included for the production of the powder involving: (i) heating a melt of a low-melting mixture of alkali nitrates, a low-chlorine platinum (Pt) compound and optionally a low-chlorine compound of the alloying element to decompose the latter 2 compounds to their oxides; (ii) cooling the melt and dissolving it in water; and (iii) reducing the (mixed) oxides to the corresponding metal(s).