Methods of the present invention can be used to synthesize nanowires with controllable compositions and/or with multiple elements. The methods can include coating solid powder granules, which comprise a first element, with a catalyst. The catalyst and the first element should form when heated a liquid, mixed phase having a eutectic or peritectic point. The granules, which have been coated with the catalyst, can then be heated to a temperature greater than or equal to the eutectic or peritectic point. During heating, a vapor source comprising the second element is introduced. The vapor source chemically interacts with the liquid, mixed phase to consume the first element and to induce condensation of a product that comprises the first and second elements in the form of a nanowire.