A mixed-metallic phosphate compound is disclosed, which contains as the main metal copper in the divalent oxidation state in a proportion of at least 90.0 at-% and one or more doping metals in a total proportion of the doping metals of at least 0.01 to at most 10.0 at-%, wherein the doping metals are selected from the group consisting of the elements of the first and second main groups and the eighth subgroup of the elements of the periodic table, Al, Sn, Si, Bi, Cr, Mo, Mn, and the lanthanides. The stated metal proportions relate to the total amount of the metals in the mixed-metallic phosphate compound. The mixed-metallic compound has a phosphate content expressed as P2O5 in the range of 10 to 60 wt-%. Also disclosed is a method for producing the mixed-metallic phosphate compound and the use thereof.