A general microwave-assisted nonaqueous approach to nanocrystalline ternary metal chalcogenide and the photoluminescence study of CoIn2S4

A new synthetic approach to nanocrystalline ternary metal chalcogenides (CoIn2S4, CuInS2, AgInS2, and CuFeS2) was developed by taking advantage of microwave irradiation and nonaqueous route in mixed amine (octadecylamine or benzylamine) and benzyl alcohol. The resulting products were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), UV–vis diffuse reflectance spectroscopy, and photoluminescence (PL). The PL analysis first indicated the unique photoluminescence property of the resulting CoIn2S4 nanocrystals and suggested its potential applications in optical devices. We found the crucial and different roles of octadecylamine and benzylamine playing for the formation of various ternary metal chalcogenides. More importantly, this study demonstrates a simple, energy efficient and time-saving approach that may be extended to prepare other promising ternary metal chalcogenide nanocrystals.

Research highlights
► A general microwave-assisted nonaqueous route for ternary metal chalcogenide was proposed.
► CoIn2S4, CuInS2, CuFeS2, and AgInS2 nanocrystals were fabricated in a short time.
► This approach possesses advantages of energy efficient, time-saving, improved yields.
► Importantly, we firstly observed the photoluminescence of CoIn2S4 nanocrystals.