Organic Photovoltaic Devices - Operation and Simulation

Organic semiconductors are an important class of material, largely due to the ability to modify their optical and electronic properties through molecular design choices, and their compatibility with low-cost, scalable manufacturing processes. Of particular interest are organic photovoltaic devices (OPVs) - solar cells - that promise sustainable, green energy for cheaper than their conventional inorganic counterparts. However, the wide range of suitable materials, which can self-assemble into many different structures, make the determination of the most efficient OPV designs an intractable problem to solve experimentally. Instead, computational simulations spanning several crucial length scales of operation within organic electronic devices are proving to be an invaluable tool to explore the sample space and identify structures that maximise the resultant device efficiency.

In this seminar, we will discuss the physical processes required to convert light into electricity, as well as describe the relative advantages and disadvantages of using organic materials to replace inorganic semiconductors (like silicon) in the manufacturing of OPVs. Several computational techniques including electronic structure calculations, molecular dynamics simulations and flavours of Monte Carlo will be explained, along with their roles in the determination of manufacturing and processing design rules for OPVs. Recent work concerning the linking of multiple techniques to fully map molecular morphology to final device efficiency will also be showcased.