The McGehee group is currently doing research on perovskite solar cells as well as dynamic windows that have adjustable tinting. This research builds on our prior investigations of organic light-emitting diodes and lasers, light extraction from LEDs, light trapping in solar cells, charge transport in organic semiconductors, nanopatterning, organic and dye-sensitized solar cells and semi-transparent electrodes based on meshes of carbon nanotubes or silver nanowires. The group is inspired to develop technology that can provide humanity with clean energy and solve environmental problems. Although all of our projects have a clear application and we interact closely with companies, we take a fundamental scientific approach that involves sophisticated characterization and advanced modeling. Our current projects are described below (Perovskite Solar Cells and Dynamic Windows), and our latest results are always posted promptly on the publications page.
Current Research Projects
Perovskite Tandem Solar Cells
Many believe that solar panels will need to have a power conversion efficiency greater than 25% and a cost below $0.4/W to revolutionize how the world's population obtains its electricity. We believe that the most promising approach to reaching this goal is to make tandem solar cells with a high band gap solar cell harvesting the high-energy photons and a lower bandgap solar cell harvesting the low-energy photons. This approach has already been used to make solar cells with power conversion efficiency greater than 45%. The remaining challenge is to figure out how to make the tandems at low cost.
Dynamic Windows
Dynamic windows utilize electrochromic materials, which change their transmission characteristics upon application of a voltage, to modulate the transparency of a window towards visible and/or infrared light. The widespread implementation of affordable and reliable smart windows in buildings would result in substantial energy savings by minimizing lighting and heating costs. Currently, however, several shortcomings have confined electrochromic windows to niche applications such as in luxury cars and airplane windows.