Using nanostructures to tailor thermal radiation for clean energy and clean water applications (Conference Presentation)

This talk will introduce some of our recent work on using nanostructures to tailor thermal radiation with applications from solar and thermal energy for electrical generation and storage, to desalination. We fabricated solar photovolatic cells with efficiency >15% using 10 micron-thick crystalline silicon films. We demonstrated that aerogels can be used for concentrated solar thermal power, eliminating the need for vacuum and wavelength selective coatings. Photovoltaic cells can couple to terrestrial heat sources to convert thermal radiation into electricity, at an efficiency higher than photovoltaics. Moving to lower temperature range, we show that fabrics can be made to radiate out human body heat while remain opaque to visible light. We also demonstrate that by localizing solar energy on water surface, we can boil water and even achieve superheated steam under one sun. The talk will end with a discussion of the entropy of light and how we exploit the understanding to design better thermal-to-electrical energy converters.