Elena Shevchenko is a master at making nanoparticles and assembling them into precise structures with useful properties. Materials made from the nanocrystals created with her methods could lead to ultra-efficient solar cells, tiny but powerful magnets, super-dense hard disks, and faster computers.

Trained as a chemist in Belarus, the University of Hamburg in Germany, and Columbia University in New York, Shevchenko has found better ways to make nanoparticles out of metallic compounds; she's produced lead telluride, cadmium selenide, and cobalt-platinum particles, among others. She has also developed a technique for assembling these nanoparticles into "superlattices," orderly crystal structures. Paul ­Alivisatos, a nanotech pioneer and interim director of the Lawrence Berkeley National Laboratory, calls Shevchenko "the best grower of nanocrystals in the world today."

Mixing and matching these nanoscale building blocks offers endless possibilities for engineering structures with desired optical, electrical, and magnetic properties. A nanoparticle array of lead telluride and silver telluride, for example, is 100 times as conductive as arrays made of either particle alone. So far, Shevchenko has created dozens of new materials. --Prachi Patel

Creating order: Top left: a crystal made from cobalt-platinum nanoparticles. Clockwise from top right: "superlattices" combining nanoparticles of lead selenide and gold, cadmium selenide and gold, and lead selenide and palladium.
Courtesy of Elena Shevchenko