A facile template-free route for synthesis of hollow hexagonal ZnS nano- and submicro-spheres

In the current paper, we report a facile template-free route for 'mass production' of ZnS hollow spheres with nano- and submicro-sizes, employing thiocarbamide, (CH3COO)2Zn·2H2O and water as the raw materials. ZnS hollow spheres were obtained via hydrothermal reaction at 140 °C for 5 h. XRD analysis showed that the as-prepared ZnS hollow spheres were of hexagonal phase structure. To the best of our knowledge, there were few reports on the preparation of hexagonal ZnS crystals under low temperature (<300 °C) in the literature. Furthermore, there is no report on the hollow structure of hexagonal phase ZnS under such low temperature (140 °C). Experimental results showed that the amount of thiocarbamide in the reaction system had a great impact on the size, shape, and structure of the final product. On the basis of the experimental results and our previous work, a possible formation mechanism was suggested.