Synthesis of Water-Soluble Antimony Sulfide Quantum Dots and Their Photoelectric Properties

Antimony sulfide (Sb₂S₃) has been applied in photoelectric devices for a long time. However, there was lack of information about Sb₂S₃ quantum dots (QDs) because of the synthesis difficulties. To fill this vacancy, water-soluble Sb₂S₃ QDs were prepared by hot injection using hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) mixture as anionic-cationic surfactant, alkanol amide (DEA) as stabilizer, and ethylenediaminetetraacetic acid (EDTA) as dispersant. Photoelectric properties including absorbing and emission were characterized by UV-Vis-IR spectrophotometer and photoluminescence (PL) spectroscopic technique. An intensive PL emission at 880 nm was found, indicating Sb₂S₃ QDs have good prospects in near-infrared LED and near-infrared laser application. Sb₂S₃ QD thin films were prepared by self-assembly growth and then annealed in argon or selenium vapor. Their band gaps (E _g s) were calculated according to transmittance spectra. The E _g of Sb₂S₃ QD thin film has been found to be tunable from 1.82 to 1.09 eV via annealing or selenylation, demonstrating the good prospects in photovoltaic application.