Scaling of inverted PTB7-Th: PC71BM organic solar cell for large area organic photovoltaic modules

Abstract

Abstract Performance studies of large area inverted organic photovoltaic (OPV) modules of configuration ITO/ZnO/PTB7-Th: PC71BM/MoO3/Ag are performed. At a laboratory of scale 0.06 cm2, this device configuration repeatedly demonstrates the power conversion efficiency (PCE) of ∼9%, which is within the range of PCE normally achieved for this configuration. The OPV modules with active area of 9.25 cm2 and 63 cm2 are fabricated employing spin coating techniques comprising a total area 25 cm2 (5 cm × 5 cm) and 144 cm2 (11 cm × 11 cm), respectively. The 25 cm2 module, composed of five cells connected in series show PCE of 3.256%, with short-circuit current (Jsc), open circuit voltage (Voc), and fill factor (FF), 3.210 mAcm−2, 3.20 V, and 31.719%. However, The 144 cm2 modules, composed of 10 cells connected in series show PCE 1.019, Jsc, Voc, and FF, 0.87 mAcm−2, 4.20 V, and 27.877%. The PCE dropped by 63.89% for modules of active area of 9.25 cm2 and 88.68% of modules of active area of 63 cm2. The PCE of the modules is decreased sharply due to loss in FF, and Jsc of the modules. These losses are exhibits due to quality of layer morphology, layer interfaces, and design of module. The PCE could be potentially improved up to the desired value by the further optimization of layer morphology, layer interfaces, design of module geometry, and film deposition/printing methods. The results showed that PTB7-Th: PC71BM is a splendid structure for future organic solar modules due to its high performance and compatibility with large area coatings.