A method of making intermetallic nanoscale particles comprising iron aluminide and/or iron aluminum carbide comprising the steps of preparing a mixture of a solvent, an iron salt and LiAlH₄, and heating the mixture to form the intermetallic nanoscale particles. The intermetallic nanoscale particles, which can comprise intermetallic nanoscale particles of iron aluminide and/or iron aluminum carbide in an alumina matrix, are capable of reducing the amount of 1,3-butadiene in the mainstream smoke of a cigarette.