Structural Analysis of Hydrothermal Assisted Growth of High-Qualities CdSe Nano-Powders for Efficient Radiation Detection

The nanostructured powders of cadmium selenide semiconductor were prepared hydrothermally using two synthesis protocols, after which they were annealed at 200°C for different times (0, 4, 8, and 12 h). In order to obtain a well-crystalline powders with a stable, single-phase structure of CdSe, and then delve into studying their structural and morphological properties and ensuring that they are completely free of impurities, that is, the presence of only the basic components of Cd and Se, while determining their atomic ratios, as well as explaining the chemical reactions occurring in both protocols, the rate of change on the CdSe nano-powders under the influence of increasing the annealing time was clear and very important until very satisfactory results were given compared to what was obtained from the hydrothermal process alone, that is, without annealing. This required the use of several techniques. The diffractograms of the two CdSe powders after a certain annealing time estimated between 4 and 8 h depending on the protocol of synthesis, showed a crystallization of pure hexagonal structure of the CdSe wurtzite phase with crystallites of nanometric size, approximately 13 nm.