Chemistry Department group finds dazzling arrangements of gold nanoparticles

Ye’s group confirmed that, “if you have a very large surface crystal, it’s essentially flat,” but something odd happened in smaller crystals of nanotetrahedra. The crystals didn’t show the expected mix of concave and convex building blocks. Instead, “only the convex motif survived,” explained Ye. The computer models hadn’t predicted this because they assumed an infinite size of the material, but experiments showed that the convex-only form appears when size is limited.

Interestingly, the gold nanotetrahedra that Ye’s group created in this project had totally different organizations and properties from ones the group had reported in 2022. The difference between the 2022 and 2023 structures was that the former had rounded vertices while the latter had sharp ones. A change as small as a rounded tip at the nanoscale level dramatically changed the material’s properties.

By studying these unique nanoparticles, Ye hopes to help scientists better understand the possibilities of material structures, opening the door for functionalized materials for energy generation, catalysis, and beyond.

This work was funded by National Science Foundation grants DMR-2102526 and CBET-2223453.