Charge Transfer Mechanism in Dilute Donor Organic Solar cells

Organic Solar Cells (OSC) based on fullerene with diluted donor content has gained attention in recent years to be an efficient alternative to provide substantial generated photocurrent and increased open circuit voltage. The main challenge using such peculiar organic solar cell architecture is to realize hole extraction pathways to generate current as there are no such percolation pathways towards the contacts as compared to the bulk heterojunction donor: acceptor blends. The current generation mechanism explained by different researchers is not yet very clear and needs further development to provide exact insight into the physics of such architecture. In this study, we set up Kinetic Monte Carlo (kMC) model for fullerene based OSC with donor material (~1%) distributed in the form of polymer chains of different lengths. The generated photocurrent by hole escape mechanism is then investigated based on the highest occupied molecular orbitals difference between acceptor and donor [1]. Furthermore, the study is extended to the different configuration and distribution of the polymer chains. As the diluted configuration has no successive percolation pathways towards the electrodes, we get confirmation that the charge can still be transferred to the electrodes without the requirement of percolation pathways and substantial current is generated only at smaller highest occupied molecular orbitals difference.     «

Organic Solar Cells (OSC) based on fullerene with diluted donor content has gained attention in recent years to be an efficient alternative to provide substantial generated photocurrent and increased open circuit voltage. The main challenge using such peculiar organic solar cell architecture is to realize hole extraction pathways to generate current as there are no such percolation p...     »