Synthesis of CdSe microspheres via solvothermal process in a mixed solution

CdSe particles with wurtzite structure have been synthesized via solvothermal method using a mixed solution of triethylenetetramine (TETA) and de-ionized water (DIW). It was found that ball-like CdSe precursor with zinc-blende phase could be transformed to wurtzite structure after heat-treating at 580 °C in Ar atmosphere and the obtained microspheres were made up of many nanometer sized CdSe particles. The experimental results were compared with CdSe obtained via hydrothermal method using N2H4·H2O as the reducing agent and it was found that CdSe nanorods with wurtzite structure were obtained. It was speculated that TETA in the mixed solution played the role of reducing agent and surfactant. Both the as-prepared products and the annealed powders were systematically characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared absorbance spectroscopy (FTIR) and thermogravimetric analysis (TGA).