Synthesis of Ag-In binary sulfide nanoparticles-structural tuning and their photoluminescence properties

In this report, we demonstrate the synthesis of binary sulfide Ag-In-S NPs using a Ag-In thiolate complex. Thermal decomposition of the thiolate complex provides Ag/AgInS2 heterostructured nanoparticles (NPs). A metathesis reaction between the thiolate complex and sulfur source leads to the formation of nearly monodispersed AgInS2 NPs with a chalcopyrite-like or orthorhombic structure. AgInS2 NPs with a chalcopyrite-like structure exhibited room temperature photoluminescence (PL). Spectral shift of the PL band depending on the excitation laser intensity and characteristic behavior of the PL decay time varying over a wide energy range within the PL band were observed. These results indicate that the PL of the AgInS2 NPs may be attributed to the donor-acceptor (D-A) pair recombination.