A Review, Water-Soluble CuInS Quantum Dots, Strategies and Photoluminescence

Abstract

Water-soluble semiconductor quantum dots (QDs) have become a unique field of materials science with great potential for applications in biomedical and optoelectronic devices. However, the more stable and bright QDs are the conventional QDs that contain toxic heavy metals such as Pb, Cd and Hg or the QDs that were synthesized in an organic phase. Hence, it is important to find an alternative material with similar optical properties and low cytotoxicity among these materials. Recently, hydrophilic CuInS2 (CIS) QDs have attracted a lot of interest due to their direct bandgap in the infrared region, large optical absorption coefficient, hydrophilicity, low cost and low toxic composition. These factors make them a good material for biomedical applications. This review starts with the origin characteristics of CIS QDs followed by various synthetic strategies, including synthesis in aqueous solvents and transformation from organic phase to water-soluble phase QDs. Then the tuning of their optical properties is discussed. The review then considers the strategies to improve the photoluminescence performances of CIS QDs.