Controlled-synthesis, Characterization And Application Of The Hierarchical Structured Tellurium

Semiconductor tellurium (Te) nanomaterials have shown someinteresting and useful properties in photoconductivity, piezoelectricity,thermoelectricity and nonlinear optical responses, which make itsapplications in fabricating electronic or photonic nanodevices anattractive and dynamic research topic. Significant progresses have beenachieved in the fabrication of one-and two-dimensional Te nanomaterials,which include nanorods, nanowires, nanobelts, and nanotubes. In contrast,the fabrication of Te micro-/nanomaterials with a three-dimensional (3D)superstructure is less explored. In this dissertation, usingdiethyldithiocarbamato tellurium (IV)(TDEC) as Te source and alow-temperature biphasic solvothermal reduction interface reaction route,various micro-/nanomaterials with3D hierarchical structures have beensuccessfully prepared. The influence of several reaction parameters on themicrostructure has been investigated. The major achievements of thisresearch are listed as follows:1. Three-branched Te crystals have been successfully synthesized,utilizing diethyldithiocarbamato tellurium (IV)(TDEC) as the Te sourceand2,2’-dithiodibenzoic acid (DTBA) as a reducing agent. Themorphology of the as-prepared Te crystals has been thoroughlycharacterized by scanning electron microscopy (SEM), X-Ray diffraction(XRD), transmission electron microscope (TEM), high-resolutiontransmission electron microscope (HRTEM), selected-area electrondiffraction (SAED), and energy dispersive X-ray spectroscopy (EDX).2. Via choosing different Te precursor and carefully adjusting otherreaction conditions such as temperature, initial concentration as well asreaction time, Te materials with various hierarchical structures have beensynthesized. These materials have been carefully characterized by thetechniques listed above.3. We used the hierarchical structured Te products as a template toobtain Te@M (Au、 Pt、 Pd) and Ag2Te core shell hybrids. These core shell hybrids are found to have a large number of edges, which shallfavor catalytic reactions. The as-prepared Te@Pd core shell hybrids hasindeed exhibited great catalytic activity in Suzuki-Miyaura cross-couplingreaction.