Study of the effect of chemical reduction agent on the synthesis and structural properties of WO3-TeO2 and MoO3-TeO2 two-dimensional compounds.

Preparation of two-dimensional nanostructures of WTe2 and MoTe2 by chemical solution synthesis methods is of great importance. In different synthesis methods, different precursors and concentrations are used. In this paper, we used the chemical reduction reaction method from solution for our analysis. Binary compounds of WO3 - TeO2 and MoO3 - TeO2 were prepared in two processes with reduction agents: (a) sodium borohydrate (NaBH4) and (b) hydrazine in the presence of nitrogen gas. The structural and optical properties of the nanopowders were studied after chemical reduction. The results of X-ray diffraction (XRD) showed that in the WO3 - TeO2 binary compound, after chemical reduction with NaBH4, the diffraction peaks of the TeO2 and WO3 binary compounds formed independently and after annealing in the presence of hydrazine, and the intensity of the peaks has been significantly increased. Field Emission Scanning Electron Microscopy (FE-SEM) images showed that the morphology of the nanoparticles was uniform in the form of spherical nanoparticles. In the combination of MoO3 - TeO2 with chemical reduction, other phases of Te2O5 and TeMo5O16 are formed in the shape of hemispheres, rods and polyhedrals, which indicates the formation of composite phases. The chemical bond structure and energy gap of samples were studied by FT-IR and UV-Vis spectroscopy.