In recent years, scientists have begun to apply multiscale computational tools to better understand the underlying patterns that govern how materials form. When combined with experiment and theory, computational tools offer new insights into principles governing materials synthesis. At PNNL, we are using this combination of theory, computation, and experiment to advance knowledge-driven synthesis of materials for applications in energy, optics, and electronics.
Understanding atomic-to-mesoscale synthesis
To control the creation of new functional materials, it is necessary to understand the forces that shape them at different scales. Our studies span the continuum from subatomic, to atomic, to molecular, to nanoscale, and beyond. These fundamental studies create foundational knowledge that will allow us to achieve real-time adaptive control over materials synthesis.
For instance, an understanding of superlattice structures formed during nanoparticle self-assembly is important to tailoring superlattice properties. However, key questions remain about how individual nanoparticles behave within emerging superlattice patterns. PNNL researchers are using advanced transmission electron microscopy equipped with direct detection camera capabilities to track individual nanoparticles in real time. Measurements obtained using these tools allow a calculation of the atomic forces competing to drive the assembly process, providing a fundamental understanding of the dynamics involved in the assembly process, and ultimately enabling investigators to control the design of nanoparticle superlattices.
Studies such as these provide the tools to predict and tune nanoparticle syntheses based on physical theories and empirical observations.
Making better materials atom by atom
Studying the nanostructure of metal alloys atom by atom allowed PNNL researchers to see their alignment and then manipulate it to make the strongest titanium alloy ever developed. The team used electron microscopy to study the metal at nanometer scale and used 3D atom probe tomography to study individual atoms at EMSL, the Environmental Molecular Sciences Laboratory, a DOE Office of Science user facility. The scientists are constructing atomic maps using this technique to see where each individual atom is located within any given sample. This new understanding could lead to the creation of light, high-strength alloys for vehicles and other industrial applications.