Inquiry 2016, Issue 1
Materials Synthesis (click cover to view issue)
From its inception, Ames Laboratory has been dedicated to materials synthesis. We developed a method for purifying uranium as part of the Manhattan Project and later used a similar technique to refine rare-earth metals. It’s even part of our corporate tagline—“Creating materials and energy solutions.”
We’re home to the Critical Materials Institute, a U.S. Department of Energy (DOE) energy innovation hub that focuses on technologies that make better use of materials and eliminate the need for materials that are subject to supply disruptions. We recently were named the lead for CaloriCool™, a new research consortium for the discovery and development of more environmentally friendly and energy-efficient refrigeration technologies, sponsored by DOE’s Office of Energy Efficiency and Renewable Energy.
While we are proud of these research efforts and plan to showcase their achievements in future issues of Inquiry, we want to focus this time on the variety of methods we employ to actually develop new materials. It’s basic science at its best, combining experimental, characterization and theoretical work to synthesize materials, measure their various properties and then work to develop models that explain a particular material’s structure and how that relates to the properties observed. That type of collaboration has also been a hallmark of Ames Laboratory.
A key method is single crystal growth, detailed on pages 8-10. By creating materials with a uniform crystalline structure, researchers can probe their properties without having to account for the effects of grain boundaries between crystals. It helps provide a clearer picture of what’s taking place within the material.
Conversely, we also create materials by cooling them very quickly so that their normal crystal patterns aren’t allowed to form. Rapid-solidification (pages 11-13), which also includes gas atomization (pages 6-7), allows for creation of materials not typically possible by other methods. The resulting properties are also out of the ordinary in many cases.
We’re also looking at creating materials in solid state (pages 14-15) without the use of solvents or high temperatures to drive the reaction to form new compounds. High-energy ball milling and friction are just two of the methods being employed to form unique materials not possible by other methods.
Our inorganic chemists are busy developing nanomaterials for possible use in solar cells and catalysis (pages 19-21). And others are studying fascinating nanoscale, two-dimensional materials (pages 16-18). In yet another technique, we are looking at the ways Mother Nature creates beautifully complex structures on multiple scales from atomic to macro. Biosynthesis (pages 22-23) is harnessing those natural processes to allow creation of man-made materials by following nature’s template.
For any of these techniques to work, it’s vital to start with pure ingredients. Otherwise, you can’t know if the resulting properties are intrinsic to the new material or caused by impurities. Fortunately, our Materials Preparation Center (detailed on pages 4-5) provides us, and researchers throughout the world, with the perfect ingredients we need for materials synthesis. Materials are everywhere and in everything, and Ames Laboratory is working hard to find new materials and new ways to create them.