Y-branched Bi nanowires with metal–semiconductor junction behavior

Y-branched Bi nanowires (NWs) embedded in anodic aluminum oxide templates were synthesized by electrochemical deposition. Transmission electron microscope observations revealed that the “stem” and the “branches” of the Y-branched Bi NWs are about 80 and 50nm in diameter, respectively. Selected area electron diffraction studies showed that both the stem and the branches are single crystalline. Current–voltage measurement revealed that the parallel Y-branched Bi NWs have characteristics of conventional metal–semiconductor junctions. Our approach to produce one-dimensional metal–semiconductor junctions using Y-branched NWs consisting of only one kind of semimetal and without any external doping can be exploited to create metal–semiconductor junctions of other semimetals, which may find various applications in nanodevices.