A method of making catalysts includes loading a quantity of catalyst material and quantity of carrier in into a plasma gun in a desired ratio and vaporizing the catalyst material and carrier in a reaction chamber, thereby forming a vapor cloud. The vapor cloud is quenched in a quench chamber to form solid nanoparticles, wherein the quench chamber comprises a frusto-conical body having a wide end, a narrow end, and a quench region formed between the wide end and the narrow end, and a reactive mixture inlet configured to receive the vapor cloud and to supply the vapor cloud into the quench region in the direction of the narrow end. The quench chamber further includes at least one conditioning fluid inlet configured to supply a conditioning fluid into the quench region in the direction of the narrow end. The nanoparticles are bonded to supports.