Flower-like morphological trigonal tellurium (t-te): A simple Wet-Chemical preparation approach to obtain semiconducting material
Aarti Saini, Kisturi Dhanwant, Khemchand Dewangan, Ramalingam Thirumoorthi, Adhish Jaiswal, Indra Bahadur, Faruq Mohammad, Ahmed A. Soleiman
Abstract
Flower-like microstructured trigonal tellurium ( t -Te) was prepared by a simple solution-based strategy with the reaction of 1,2,3,4,5-pentamethylcyclopentadiene (HCp*) and TeCl 4 in tetrahydrofuran (THF) under reflux condition. Powder X-ray diffraction (XRD) and electron microscopy techniques confirmed the phase purity and morphology of the synthesized sample. X-ray photoelectron spectroscopy (XPS) analysis provides evidence for forming elemental Te, viz, Te (0). Also, XPS analysis indicates the presence of a higher oxidation state, i.e., Te(IV), which may be due to the formation of an ultrathin layer of TeO 2 on the surface of the elemental t -Te microstructure. According to the synthetic strategy, higher oxidation is due to the surface oxidation of Te (0) to Te(IV) while washing the sample. Additionally, Fourier-transform infrared (FTIR) technique further supports the presence of Te–O bonds on the surface of t -Te. The semiconducting behavior of the prepared elemental t -Te microstructure was confirmed by obtaining a positive Hall coefficient ( R H ) value of 4.98 × 10 3 cm 3 C −1 . In addition, the resistivity (conductivity) value, i.e., 1.05 × 10 2 Ω cm (9.52 × 10 −4 Ω −1 cm −1 ) is calculated using Hall-effect measurement.