We propose a low cost solution-based approach to synthesize various low dimensional copper telluride (Cu-Te) nanostructures. By precisely controlling different ethylenediamine (EDA) ratios in a reaction solution, we are able to control the phases and morphologies of Cu-Te nanostructures from Te/Cu core-shell nanowires at a low volume fraction of EDA <8%, Cu 3 Te 2 nanowires at the volume fraction of EDA between 8% and 24%, Cu 2 Te nanowires and nanobelts at the volume fraction of EDA between 24% and 48%, to Cu 2 Te/Cu core-shell nanobelts at the volume fraction of EDA over 48%. The formation mechanism is attributed to varied tendency of different coordinative copper complexes. In situ heating XRD results and TEM observations of the Cu 2 Te nanowires reveal the phase transition from hexagonal P3m1, hexagonal P6/mmm to cubic structure at annealing temperatures of 25 C, 500 C to 600 C, respectively. The lack of back gate dependence demonstrates the metallic feature of Te/Cu core-shell nanowire while obvious p-type behavior can be found for Cu 2 Te nanowire with an on/off ratio of $10 4 and the field effect hole mobility of $18 cm 2 V À1 s À1 . These Cu-Te nanostructures exhibit controllable transport behaviors from metallic to semiconducting natures with different EDA volume fractions and have promising applications in electronics such as nonvolatile memory, photodetectors, and solar cells.

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High-aspect-ratio Fe(1-x)Mn(x)Si nanowires with room-temperature ferromagnetism were synthesized by a chemical vapor deposition (CVD) method in one step. This is the first report of ternary silicide nanowires using magnetic Mn ions to partially replace metal sites in the host matrix. Here we report the excellent magnetic characteristics of Fe(1-x)Mn(x)Si nanowires, which exhibit strong ferromagnetism at room temperature and high magnetoresistance (MR) variation. As-synthesized Fe(1-x)Mn(x)Si nanowires show a hyperbranched morphology and a spin-disorder behavior. The strong spin interaction in Fe(1-x)Mn(x)Si nanowires, induced by the substitution of Fe sublattices for magnetic Mn ions, was revealed in the hysteresis loops. The magnetization versus magnetic field (M-H) curves of Fe(1-x)Mn(x)Si nanowires are much less sensitive to the temperature variation from 10 to 300 K than those of FeSi nanowires. Remarkably, the excellent MR performance, -41.6% at 25 K with a magnetic field of 9 T, was demonstrated in an individual Fe(0.88)Mn(0.12)Si nanowire.

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