Facile synthesis of flake-like nickel disulfide nanocrystallites

Pure cubic pyrite flake-like nickel disulfide nanocrystallites have been successfully synthesized by thermal decomposition approach under open-air conditions at 280 °C using bis(thiourea) nickel (II) chloride crystals as precursors. The crystallinity and morphology of the products were found to be dependent on the reaction temperature. Raman spectroscopy study indicates that peak of flake-like nickel disulfide located at 478.7 cm−1 should correspond to a stretching vibration with an Ag mode. Magnetization measurement indicates that as-prepared product at 280 °C under open-air condition displays anomalous magnetic property at room temperature and shows weak ferromagnetic. The present thermal approach in a complex system may allow synthesizing other metal chalcogenides by decomposing under open-air conditions.