Effect of Thickness and Temperature on Bulk Heterojunction Organic Solar Cells Performance

Bulk heterojunction (BHJ) organic solar cells made from blends of two conjugated organic polymers or small molecules have attracted considerable attention over the past two decades due to their potential for solar energy generation at low manufacturing cost, light-weight, flexibility and simple large-scale fabrication. Among the blended materials systems used in BHJ devices, the one comprising is, the Poly({4,8-bis[(2-ethylhexyl) oxy] benzo[1, 2-b:4,5-b′] dithiophene-2,6-diyl} {3-fluoro-2-[(2-ethylhexyl) carbonyl] thieno[3,4-b] thiophenediyl}) (PTB7) as the electron donor and [6,6]-phenyl C71 butyric acid methyl ester (PC70BM) as the electron acceptor. In this work, we presented numerical simulation and optimization of BHJ solar cells based on PTB7:PC70BM. However, the effect of layer thickness is analyzed to obtain the maximum performance characteristics, using GPVDM software. Then, the effect of temperature is investigated. Several electrical parameters are studied including short circuit current density (Jsc), Open circuit voltage (Voc), fill factor (FF) and power conversion efficiency.