Nanostructured copper sulfides: synthesis, properties and applications
Among different metal chalcogenides, copper sulfides have been extensively studied in the past few years due to their semiconducting and non-toxic nature, making them useful in a wide range of applications from the energy to the biomedical fields. A series of stoichiometric compositions of copper sulfides from Cu-rich, Cu2S to Cu-deficient, CuS2 exist with different crystal structures as well as phases, resulting in different unique properties. The suitable band gap values in the range of 1.2–1.5 eV and unique optoelectronic properties indicate that the material is photocatalytically active and exhibits excellent plasmonic behavior. The material is also known for promising thermoelectric properties, converting waste heat into electricity through the Seebeck effect. The nanodimensional form of copper sulfides promotes their use to a more advanced level, tuning their properties with the size of the materials. In view of this, the present review article is focused on the compositions, phases and crystal structures, and different synthetic methodologies involved in the fabrication of 0D, 1D and 2D nanostructured copper sulfides. Moreover, recent advancements on their use in various applications will also be briefly discussed.