E. Kluender et al., PNAS 10.1073 (2018)

‘Megalibraries’ of nanomaterials could speed clean energy and other grand challenge targets

Lightweight armors, synthetic fuels, and new high-efficiency solar cells could all be the outcome of a new high-speed technique for discovering advanced materials made from ultrasmall flecks of matter.

In the materials world, size matters. Particularly on the smallest length scales of just billionths of a meter, or nanometers. Nanomaterials are famous for having different optical, electrical, and catalytic properties than bulk chunks of the exact same stuff. But that makes exploring the endless possible combinations of multiple elements of different nanoscale sizes a near impossibility.

Now, there’s help. Researchers have come up with a high-speed approach to make “megalibraries” of up to 5 billion combinations of different nanomaterials that vary in a controlled manner, based on the concentration of different elements they contain and the sizes of the resulting particles. To make the arrays, the team used a specialized device that contains hundreds of thousands of pyramid-shaped tips to stamp individual polymer wells of various sizes and composition, each loaded with different metal salts of interest. The stamped surface is then heated, burning away the polymer and causing the metals to form alloy particles.

The scientists tested one such array, pictured above, and discovered a new catalyst able to make straw-shaped carbon nanotubes—prized for their ultrahigh strength and ability to serve as tiny high-speed transistors—faster than any catalyst previously discovered, as they report this week in the Proceedings of the National Academy of Sciences. The discoveries aren’t likely to stop there, as the researchers plan to test myriad other nanomaterials in search of new and improved catalysts, electronic, and optical materials.