Facile, one-step controlled synthesis of Se nanocrystals in the presence of l-tyrosine

Se with different morphologies was synthesized using l-tyrosine as reducing agent and soft template by means of hydrothermal method. The method was simple and convenient to handle. The reaction process was monitored using ultraviolet-visible spectroscopy (UV-vis) and Fourier-transform infrared spectroscopy (FTIR). The morphology and crystalline phase were determined by transmission electron microscopy (TEM), scanning electronic microscopy (SEM) and X-ray diffraction (XRD) pattern. The results show that the morphologies and the crystalline phases of Se can be easily controlled. By varying the concentration ratio of l-tyrosine to selenious acid, the morphologies and crystalline phases of Se were not changed, but the diameter of Se was different. Se nano-rods are obtained in the lower temperature, and there is a transformation of microspheres into nanorods of Se with the increase of reaction time or reaction temperature. In addition, we discuss the possible mechanism of the reduction of SeO₃²⁻ ions by l-tyrosine. The eco-friendly, biogenic synthesis strategy could be widely used for preparing inorganic/organic biocomposites.