The invention provides a catalyst, a method for making the catalyst and a method for using the catalyst to promote the selective oxidation of hydrogen sulfide into elemental sulfur. The catalyst may be prepared by contacting a catalyst support, such as silica, with a mixed oxide having atomically mixed iron ions and zinc ions, to produce a support material impregnated with a mixed oxide having atomically mixed iron ions and zinc ions in an oxidic lattice. This impregnated catalyst support is then dried and calcined, preferably with chloride ions present, to produce a catalyst of an iron and zinc oxide mixture supported on silica. It has been found that when chloride is added to the impregnated catalyst support prior to calcination and drying, the sintering of the iron and zinc can be controlled more easily and the formation of iron and zinc oxide is promoted. It has also been found that the catalyst of the invention exhibits improved selectivity characteristics when compared to a catalyst prepared without the chloride.