Achievement

Solar energy has minimal impact today, because the leading technology, which is based on crystalline silicon, is very expensive ($350/sq. m) albeit efficient (~10%). Organic semiconductors may be an affordable alternative, but organic solar cells do not currently have competitive efficiencies. IGERT Fellow Rebecca Cantrell has been performing multiscale simulations of C60/pentacene devices -- a system with promising characteristics. One of the main challenges in fabricating these devices is achieving layer-by-layer growth of crystalline films, which is necessary for high efficiency. On the smallest scale, Cantrell uses ab initio calculations to model the electronic properties of the crucial C60/pentecene interface where charge separation occurs. She also uses macroscopic methods to simulate growth under a variety of conditions. Her simulations are complemented by experiments by collaborators at NIST. Together, they have achieved a new understanding of C60 growth on pentacene.