See-Through Solar Is Tomorrow’s Threat to Oil
April 29, 2015
Faculty Highlight: William Tisdale - Understanding and Controlling How Energy Moves
March 23, 2015
MIT Students Bring Nanotechnology to the Masses at Boston’s Museum of Science
March 20, 2015
MIT Deshpande Center Announces Fall 2014 Research Grants
October 8, 2014
Material gain: Research a step toward more efficient solar panels
October 7, 2014
Developing new light and energy technologies
August 20, 2014
Nano-Structured Solar Cells
August 11, 2014
Energy and Sustainable Chemistry: Light Harvesting & Biocatalysis
July 14, 2014
Supran, G. J., Song, K. W., Hwang, G. W., Correa, R. E., Scherer, J., Dauler, E. A., Shirasaki, Y., Bawendi, M. G. and Bulović, V. , "High-Performance Shortwave-Infrared Light-Emitting Devices Using Core–Shell (PbS–CdS) Colloidal Quantum Dots" Adv. Mater., 27: 1437–1442. doi:10.1002/adma.201404636, Jan 2015.
October 20, 2015 | 4:30pm/36-428
Department of Chemistry, Department of Materials Science and Engineering, Department of Physics and Astronomy, Institute for Quantum Matter, The Johns Hopkins University
What is an Exciton?
When a chlorophyll molecule in the leaf of a plant absorbs a photon of sunlight, the solar energy is converted into an excited state of the molecule known as an exciton. The exciton then transports the energy between molecules in the leaf, and ultimately mediates the conversion of sunlight into electrical energy.
Thus, excitons are packets of energy confined within a material. They are the crucial intermediate for energy transduction in all kinds of low-cost electronic materials. Excitons also dominate the behavior of disordered synthetic nano-materials like polymers and inorganic quantum dots. Consequently, excitons control solar energy conversion in low-cost solar cells, and also light emission in organic and quantum-dot based LEDs.