The effect of different annealing temperatures on tin and cadmium telluride phases obtained by a modified chemical route

Abstract

In this work tin and cadmium telluride were prepared by a modification of a chemical route reported in the literature to obtain metallacycles formed by oxidative addition of tintellurium bonds to platinum (II). Through this procedure it was possible to obtain tin and cadmium telluride. X-ray diffraction and X-ray photoelectron spectroscopy were used to identify the crystalline phases obtained as well as the presence of side products. In the case of tin telluride it was identified potassium chloride, metallic tellurium and tin oxide as contaminants. The tin oxidation states were also monitored by 119Sn Mössbauer spectroscopy.The annealing in hydrogen atmosphere was chosen as a strategy to reduce the tin oxide and promote its reaction with the excess of tellurium present in the medium. The evolution of this tin oxide phase was studied through the annealing of the sample at different temperatures. Cadmium telluride was obtained with high degree of purity (98.5% relative weight fraction) according to the Rietveld refinement of X-ray diffraction data. The modified procedure showed to be very effective to obtain amorphous tin and cadmium telluride and the annealing at 450°C has proven to be useful to reduce the amount of oxide produced as side product.