Cottrell Scholar Awards - 2015
Designing Photocathode Materials for Solar Fuel Photoelectrosynthesis: From the Lab to the Classroom
Sunlight promises to be an endless source of energy for humankind. But it would be nice to be able to efficiently store some of it for use in the dark, or to concentrate it to power heavy equipment and airplanes.
James F. Cahoon, assistant professor of chemistry at the University of North Carolina-Chapel Hill, has received Cottrell Scholar funding to perfect one way of doing that.
Cahoon is working to develop high-performance photocathode materials for use in the process of producing liquid fuel from sunlight. A cathode and its inseparable twin, an anode, are basically the two terminals on any car battery. The anode is the terminal where electrical current flows in from outside; the cathode is the terminal where current flows out.
Solar fuels are produced by using sunlight to generate electricity to split molecules like water (H2O) and carbon dioxide (CO2) to create chemicals that can be burned in an engine, much like gasoline or diesel fuel. Combustion, of course, releases the energy stored in the chemical’s molecular bonds.
Cahoon is attempting to create and evaluate new types of light-activated cathodes by developing nanomaterials with high surface areas, and thus increased efficiency, to produce and conduct electrical charge when exposed to sunlight, and while immersed in water or carbon dioxide.
Cahoon’s work could one day lead to cheap and abundant liquid fuels.
He is also using some of his Cottrell Scholar funds to bring three-dimensional (3D) printing of crystals and molecules, using open-access 3D printers, to his classroom at UNC-Chapel Hill. (Crystalline structures are important for semiconductors, the materials used in computer chips, as well as in the production of electricity from sunlight.)
“The technology to print accurate representations of complex, extended crystals is readily accessible, but has yet to be applied as a general tool for undergraduate instruction,” he said, adding that he is developing web tutorials and workshops demonstrating 3D printing for undergraduates.