Facile and controllable synthesis of NiS2 nanospheres in deep eutectic solvent

Abstract A facile and controllable approach was used to synthesize NiS2 nanospheres for the first time, and the process was carried out in choline chloride-ethylene glycol deep eutectic solvent (ChCl-EG DES) under normal atmosphere. The effects of reaction temperature on the phase and microstructure of the products were investigated. It is found that the high-purity and well-crystallized NiS2 was synthesized at 110 °C for 3 h and confirmed by the XPS test. The uneven surface and some small bumps were observed on the nanoparticle. In the synthesis process, DES acts as a solvent, providing a mild reaction environment for the synthesis that significantly reduces the requirements for experimental equipment and conditions.