Simple and Green Synthesis of Lead Sulfide Nanocrystals for Hybrid Bulk Hetero-Junction Solar Cells

High quality PbS nanocrystals (NCs) were successfully synthesized through a facile, inexpensive and reproducible hot injection method using low-cost and less-injurious thioacetamide (TAA) as a sulfur source in the presence of oleylamine (OLA) and oleic acid (OA). The as-synthesized PbS NCs showed strong absorption and photoluminescence (PL) emission in the near-infrared region. The size of the PbS NCs was easily controlled in the range, 3.8 similar to 6 nm by varying the reaction conditions such as reaction temperature (R-T), OLA/OA ratio, and Pb/S ratio. Larger sizes of PbS NCs were obtained at higher R-T, and lower OLA/OA ratio, and Pb/S ratio values. The developed PbS NCs in the present study have potential application in the fabrication of solar cells.