Crystallographic, optical, photoluminescence and electrical properties of CuS quantum dots: Influence of ethylenediamine

Copper sulfide (CuS) is a semiconductor widely used for quantum dot sensitized solar cell applications due to its photocatalytic activity. The hydrothermal technique was used to synthesize the copper sulfide quantum dots. The distilled water and ethylenediamine are served as solvents with different combinational ratios. According to TEM studies, the particles' size increased as the solvents' ratio decreased. XRD patterns revealed that the synthesized CuS QDs are polycrystalline with a hexagonal structure. UV–vis results showed that the absorption of CuS QDs is from 310 nm to 320 nm, and the band gap of synthesized quantum dots is found to be ∼3.7 eV. Photoluminescence spectra illustrate that the CuS quantum dot emission spectrum was observed at 475 nm (blue emission) and 570 nm (green emission). The highest power conversion efficiency (0.5390 %) was received for the 25:75 ratio of DI Water/EN using the CuS quantum dot. It is observed as better photon conversion efficiency among all the ratios with lesser charge recombination.