SnS₂ quantum dots: Facile synthesis, properties, and applications in ultraviolet photodetector

Tin sulfide quantum dots (SnS₂ QDs) are n-type wide band gap semiconductor. They exhibit a high optical absorption coefficient and strong photoconductive property in the ultraviolet and visible regions. Therefore, they have been found to have many potential applications, such as gas sensors, resistors, photodetectors, photocatalysts, and solar cells. However, the existing preparation methods for SnS₂ QDs are complicated and require a high temperature and high pressure environments; hence they are unsuitable for large-scale industrial production. An effective method for the preparation of monodispersed SnS₂ QDs at normal temperature and pressure will be discussed in this paper. The method is facile, green, and low-cost. In this work, the structure, morphology, optical, electrical, and photoelectric properties of SnS₂ QDs are studied. The synthesized SnS₂ QDs are homogeneous in size and exhibit good photoelectric performance. A photoelectric detector based on the SnS₂ QDs is fabricated and its JV and CV characteristics are also studied. The detector responds under λ = 365 nm light irradiation and reverse bias voltage. Its detectivity approximately stabilizes at 10¹¹ Jones at room temperature. These results show the possible use of SnS₂ QDs in photodetectors.