Preparation of Fluorescent Tellurium Nanowires at Room Temperature

Abstract

We have demonstrated a simple approach to the synthesis of fluorescent trigonal tellurium (t-Te) nanowires in aqueous solution at room temperature. The t-Te nanowires were prepared from the reduction of tellurium dioxide (TeO 2 ) with concentrated hydrazine solution through deposition of Te atoms that were reduced from telluride ions (Te 2-) and dissolved from amorphous tellurium (a-Te) nanoparticles onto t-Te nanocrystallines. By carefully controlling the growth time from 40 to 120 min, we prepared different sizes of t-Te nanowires; the length changed from 251 to 879 nm, while the diameter only grew from 8 to 19 nm. The absorption wavelength against the diameter of t-Te nanowires displays the diameter dependence of band I (<300 nm). On the other hand, the absorption wavelength against the length of t-Te nanowires displays the length dependence of band II (>600 nm). By increasing the size of t-Te nanowires, their absorption is under a red shift. For example, the maximum wavelengths of the absorption bands for the t-Te nanowires with the lengths of 251 nm are 271 and 602 nm, while those for 879 nm t-Te nanowires are at 280 and 687 nm, respectively. Deconvolution of the photoluminescence profile for t-Te nanowires obtained at 120 min yields four Gaussian peaks centered at 334, 397, 460, and 507 nm.

Heterojunction double dumb-bell Ag2Te–Te–Ag2Te nanowires

“…A gradual red shift (shown by an arrow) in the band maxima of partially silver reacted NWs with annealing time was seen; attributed to growth and increase in length of the Te region in the NW body. 17 The observation predicted from the UV-vis data was confirmed from the TEM images taken by stopping the reaction at different time intervals during solution phase annealing (Fig. S7 †).…”

“…To the best of our knowledge, this is first time report of rod shaped secondary structures grown along the wire axis to produce dumbbell shaped heterostructures of tellurium in solution. 17 In a typical procedure, 24 mg of TeO 2 powder was slowly added to a beaker containing 10 mL of hydrazine monohydrate. The reaction was allowed to continue at room temperature under constant magnetic stirring.…”

Lanthanum Telluride Nanowires: Formation, Doping, and Raman Studies

“…Lattice resolved HRTEM image of a single Te NW ( Figure 1E) shows the interplanar spacings of 0.59, 0.39, and 0.22 nm which correspond to (001), (010), and (110), respectively. 35 All the NWs were straight and have uniform morphology. There was no dislocation and planar defects on the NWs, which suggest that the NWs are single crystalline.…”

“…Peak II is due to the transition from p-lone pair valence band (VB3) to the p-antibonding conduction band (CB1) and it appears around 600-850 nm. [35][36][37] In this particular synthesis, peak I appeared at 284 nm and peak II appeared at 716 nm ( Figure 1A). XRD pattern of Te NWs is shown in Figure 1B.…”

“…Sodium dodecyl sulfate (SDS, C 12 35 In a reaction, 16 mg of TeO 2 powder was slowly added to a beaker containing 10 mL of hydrazine hydrate. The reaction was allowed to continue at room temperature under constant stirring.…”