Characteristics and Fabrication of an Inverted Organic Photodiode Using CdSe Core/ZnS Shell Quantum Dots As an Electron Transport Material

To achieve high detectivity of organic photodetectors (OPDs), we incorporated CdSe core/ZnS shell quantum dots (CdSe@ZnS) in devices consisting of ITO/tin oxide (SnO 2 )/CdSe@ZnS/(poly(3-hexylthiophene-2,5-diyl)[P3HT]:PC 60 BM)/MoO 3 /Ag. We found that the CdSe@ZnS layer has a significant role in enhancing photocurrent and reducing leakage current simultaneously by transferring energy from the quantum dot buffer layer to the wide band gap of the ZnS shell. As a result, the device with the CdSe@ZnS quantum dot buffer layer shows enhancement of the photocurrent by 13.2%, reduction in the dark current from 8.28 µA/cm 2 to 1.06 µA/cm 2 , and detectivity of 1.43 × 10 12 Jones. Graphical Abstract