CEMS Department News
Renewable Energy Within Reach: Associate Professor Russell Holmes and research team develop new approach to exciton diffusion
In a recent Nature Materials publication entitled: “Tailored exciton diffusion in organic photovoltaic cells for enhanced power conversion efficiency”, Matt Menke, Wade Luhman and Prof. Russell Holmes outline the fundamental mechanisms responsible for exciton diffusion at the nanoscale in organic semiconductors. Organic solar cells are a promising source of inexpensive renewable energy due to their optical tunability and compatibility with large-area processing techniques. To date, the short, characteristic diffusion length of the exciton has been a design bottleneck necessitating the need for complex and often poorly understood film morphologies. In this new work, Menke, Luhman and Holmes lay out a new approach to directly enhance the characteristic exciton diffusion length via dilution of the absorbing active material in a optically transparent host. This new ability to tailor exciton diffusion in organic semiconductors could have broad implications for future active material and device design for the realization of high power conversion efficiency solar cells.
Link to Holmes Research Group: http://research.cems.umn.edu/holmes/