Room-Temperature Chemical Synthesis of Silver Telluride Nanowires

Abstract

We have developed a room-temperature solution-phase route for the preparation of one-dimensional silver telluride nanowires (Ag2Te NWs). The Ag2Te NWs of 600 nm length and 20 nm diameter were synthesized by the reaction of tellurium nanowires (Te NWs) with silver nitrate (AgNO3) in water. We propose that Te NWs act as the template and the reducing agent simultaneously, enabling the formation of polycrystalline Ag2Te NWs. Various microscopic and spectroscopic tools, such as HRTEM, SEM, EDAX, XRD, DSC, XPS, and Raman, were used for the characterization of Ag2Te NWs. The phase transition corresponding to the structural transition from the low-temperature monoclinic phase to the high-temperature face-centered cubic phase occurs at 417.7 K. We studied the electrical resistance and investigated the influence of temperature on the thermal emf. The Seebeck coefficient showed a maximum of ∼142 μV K−1, a value much higher than that of the bulk material and thin films (65−130 μV K−1). A surface-enhanced Raman scattering investigation of dispersed Ag2Te NWs showed them to be sensitive up to 10−7 M crystal violet. The monodispersity and the homogeneity of the NWs through a simple solution-phase protocol would pave the way for further studies and applications.