Copper Indium Sulfide Colloidal Quantum Dots: Advances in Synthesis, Structure-Optoelectronic Properties, and Applications

The discovery of quantum dots (QDs) stands as one of the paramount technological breakthroughs of the 20th century. Their versatility spans from everyday applications to cutting-edge scientific research, encompassing areas such as displays, lighting, photocatalysis, bio-imaging, and photonics devices and so on. Among the myriad QDs technologies, industrially relevant CuInS2 (CIS) QDs have emerged as promising alternatives to traditional Cd- and Pb-based QDs. Their tunable optoelectronic properties, high absorption coefficient, compositional flexibility, remarkable stability as well as Restriction of Hazardous Substances-compliance, with recent trends revealing a renewed interest in this material for various visible and near-infrared technological applications. This review focuses on recent advancements in CIS QDs as multidisciplinary field from its genesis in the mid-1990 to date with an emphasis on key breakthroughs in their synthesis, surface chemistry, post-synthesis modifications, and various applications. First, the comparation of properties of CIS QDs with relevant knowledge from other classes of QDs and from I-III-VI semiconductors as well is summarized. Second, recent advances in the synthesis methods, structure-optoelectronic properties, their defects, and passivation strategies as well as CIS-based heterostructures are discussed. Third, the state-of-the-art applications of CIS QDs ranging from solar cells, luminescence solar concentrations, photocatalysis, light emitting diodes, bioimaging and some emerging applications are summarized. Finally, we discuss open challenges and future perspectives for further advancement in this field.