Prediction of key photoelectric parameters at the interface of new subAPPC/C60 organic solar cell

Abstract

In organic solar cells (OSCs), morphology at the interface between donor and acceptor always have important impact on their performance. Unfortunately, it is always hard to measure and explore the morphology and electronic structure at the interface experimentally. In this paper, subazaphenalenephthalocyanine (subAPPC), a derivative of popular boron subphthalocyanine chloride (subPC) with a core-expanded six-membered ring, is selected to pair with C60 fullerene. The purpose is to explore how the molecular arrangements at donor-acceptor interface influence the optoelectronic properties of this new OSC and to test whether this new solar cell is superior to popular subPC/C60 solar cell because subAPPC seems to have great potential. Then, by modeling five configurations (B/U stands for C60 on/in the convex/concave of subAPPC, respectively), the calculated results of density functional theory (DFT) and time-dependent DFT show that different molecular orientations have significant effects on interfacial photovoltaic properties such as absorption spectrum, open circuit voltage, and exciton binding energy. Finally, new subAPPC/C60 solar cell may be superior to prototype subPC/C60 because simulated absorption is enhanced and predicted VOC could be higher at the interface of B configurations. However, in U configuration, subAPPC/C60 has a very low VOC, which suggest that U configuration should be prevented during fabrication process of this new solar cell.