A green and low-cost approach for the large-scale production of uniform t-Se microspheres and their photoluminescence properties

A green and economical hydrothermal route was developed to synthesize uniform trigonal selenium (t-Se) microspheres with an average diameter of 1 µm by using ascorbic acid (Vc) as a mild reducing agent and Se powder as the selenium source. The as-prepared products were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Experimental results reveal that the morphology of t-Se microspheres is strongly dependent on the reaction conditions such as the amount of Vc, reaction temperature and reaction time. The tentative growth mechanism of t-Se microspheres is also discussed in this letter. Photoluminescence spectrum indicates that the t-Se microspheres with an average diameter of 1 µm exhibit a strong red-emitting peak at 675 nm.