Ionothermal/hydrothermal synthesis of the ternary metal chalcogenide ZnIn2S4

The ternary metal chalcogenide ZnIn2S4 was synthesized through the ionothermal/hydrothermal method using the ionic liquid [Bmim][BF4]. The crystal structure and surface chemical state of the product were confirmed by X-ray diffractometry and X-ray photoelectron spectroscopy. A small amount of water was essential for the obtaining of yellow ZnIn2S4 product. ZnIn2S4 with a hexagonal phase was obtained in a wide range of [Bmim][BF4]:water ratios of 9.3 ml:(0.1–5 ml). The size and morphology of the synthesized samples were strongly affected by the aid of [Bmim][BF4], the amount of water, the zinc source, reaction temperature, and reaction time. The ZnIn2S4 showed different visible light absorption ranges when the water content of the reaction mixture was varied.