Chemists have found a way to make nanocrystals from metal nitrides, a class of materials that had defied earlier attempts at nanoscale production. Researchers at the University of Chicago and Argonne National Laboratory described the method in a study published in Nature. The results could turn everyday materials used in LED lights, medical implants and superconductors into building blocks for a new generation of flexible and printable devices.
A long-standing problem
Nanocrystals are microscopic crystals that have become a central part of modern materials science. Quantum dots, a type of nanocrystal, helped inspire the 2023 Nobel Prize in Chemistry. But researchers had only managed to make these tiny structures from a narrow range of materials. Metal nitrides, which are valued for being hard, stable and useful in electronics, resisted conventional nanocrystal synthesis at the sizes and scale needed for real applications. That left a gap between the materials industry depends on and the materials scientists could shrink down to the nanoscale.
Nearly a dozen new materials
The method opened up a much larger set of targets. "We were able to show how to make a series of nearly a dozen materials that could not be synthesized by traditional methods," said Ruiming Lin, a graduate student at the University of Chicago and first author of the study. The crystals are so small that billions could fit on a fingernail, the team said, and electron microscope images confirmed the results.
What the materials could do
Metal nitrides already power many technologies. Gallium nitride is widely used in LED lighting and displays. Titanium nitride appears in medical implants. Niobium nitride acts as a superconductor, and molybdenum nitride works as a catalyst. Until now, these materials could mostly be used in rigid, bulky forms. In nanocrystal form, they could be printed onto flexible surfaces, used in new kinds of lighting, or built into medical devices that bend and move with the body. The researchers say the recipe gives engineers a much larger toolbox for designing the devices of the future.