Catalytic synthesis of matchstick-like Ag2Se-ZnSe hetero-nanorods using Ag2S nanocrystals as seeds

In nanowire catalytic growth, the catalyst particles usually remain at the tip of as-grown nanowires, which can be utilized to prepare matchstick-like heterostructures at the nanoscale. Based on this feature and a solution-phase catalytic growth route, we herein report the synthesis of Ag2Se-ZnSe matchstick-like hetero-nanorods, consisting of Ag2Se head and ZnSe rod-like stem. Three different kinds of silver sources, including Ag(0), Ag2S, and Ag2Se, are selected as initial seeds for growing ZnSe crystalline nanowire/rods. By comparison with the case of Ag(0) or Ag2Se, the use of Ag2S nanoparticles, which alter the chemical composition of catalytic particles and convert to Ag2Se catalyst after adding Se precursor (SeO2), is highly effective for the formation of uniform Ag2Se-ZnSe hetero-nanorods. The reason for this result may be attributed to a synergistic effect between the size of catalyst particles and the chemical conversion of Ag2S to Ag2Se.