Moderate temperature synthesis of flower- and dot-shaped HgS nanocrystals

We report a simple, robust, reproducible and phosphine-free approach to synthesize zinc-blende HgS nanocrystals with both flower and dot shapes at moderate temperatures. 1-Octadecylamine was used to effectively adjust the activity of mercury ions. HgS nanoflowers were synthesized with S precursors prepared at temperatures between 100 °C and 210 °C, while individual dot-shaped HgS nanocrystals were obtained when the temperature to prepare S precursors was higher than 210 °C. We proposed that the structure difference of S molecules due to different heating temperatures might affect the final shape of nanocrystals. The as-prepared HgS nanocrystals were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV–vis absorption spectroscopy.