Solar Energy Conversion and Lighting
We seek new insights into the fundamental chemistry and physics that control interface formation and electron transfer phenomena by pushing the limits of digital materials synthesis. In so doing, we ascertain and influence the arrangement of atoms for specifically designed functionalities.
The efficient harvesting and use of renewable energy sources can be greatly improved by the development of new materials. The Materials Science Division’s unique capabilities are used to develop new materials for high-performance solar-to-electricity and solar-to-fuels technologies as well as wide bandgap (WBG) semiconductors for efficient use (e.g. lighting) and distribution (e.g. high performance DC-DC voltage conversion).
The efficient and affordable conversion of solar energy to electricity or fuels remains a technological holy grail owing to the colossal, albeit diffuse, solar resource. In order to address our terawatt energy needs, we pursue the discovery and understanding of breakthrough solar energy conversion technologies. These include the use of earth-abundant absorbers (Cu2S, Fe2O3), controlled size and shape clusters for (electro)catalysis, and new conversion approaches with theoretical capabilities to break through the traditional limits on power conversion efficiency – namely intermediate band absorbers and thermophotovoltaics. Disruptive designs are enabled through the precise spatial and chemical control afforded by atomic layer deposition (ALD). These studies explore the intersection of earth-abundant materials, photoelectrochemistry, and targeted interface synthesis in order to study their synergies and enable greater control over energy and matter.
WBG semiconductors such as GaN have enormous potential for revolutionizing the control, transmission and utilization of electrical power. Their high speed performance, ability to switch very high voltages, and tolerance for high-temperature operation can improve important applications such as conditioning of power from wind and solar arrays, eliminating transformers and their inefficiencies in transmission applications, and managing power flows in electric vehicles. We explore the underlying physical and chemical processes associated with the growth of WBG semiconductors. By using state-of-the-art synchrotron techniques, we identify common mechanisms and highlight differences between different growth techniques. Using Argonne’s advanced computational capabilities, we develop detailed theories describing the growth processes, and mesoscale models that predict the strain evolution and defect generation accompanying processing.