Researchers from the University of Illinois at Urbana-Champaign and Northwestern University have made it possible to observe and simulate the self-assembly of crystalline materials at a much higher resolution than before.
Using computer modeling and an imaging technique called liquid-phase electron microscopy, the team pinpointed the individual motions of tiny nanoscale particles as they orient themselves into crystal lattices. The work confirms that synthetic nanoparticles – the fundamental building blocks of many synthetic and biological materials – can assemble in ways far more complex than larger particles, the researchers said, and paves the way to more general applications for mineralization, pharmaceuticals, optics and electronics.
The new study, led by Qian Chen, a professor of materials science and engineering at the U. of I., and Erik Luijten, a Northwestern professor of materials science and engineering and of engineering sciences and applied mathematics, is published in the journal Nature Materials.
“Imaging and modeling are routinely performed for particles about 1 micrometer in size,” said Luijten, who led the computation modeling portion of the study. “Here, we have newly developed techniques that can do this for particles that are 100 nanometers in size – 10 times smaller than before.”
Because nanoparticles are very small and interact in liquid solutions, verifying their crystallization pathways through direct observation was not possible before liquid-phase electron microscopy, said Chen, who led the experimental portion of the study.
Chen’s team performed laboratory experiments using tiny gold prisms in a fluid, watching closely as the particles began to interact with each other.
Source: “Crystallisation clarified, researchers report”, Louis Yoksoulian, University of Illionis