Nanofluidic Trapping of Faceted Colloidal Nanocrystals for Parallel Single-Particle Catalysis

In this paper, we studied the catalytic performance of selectively trapped individual spherical, cubic, and octahedral gold nanocrystals in 100 parallel nanofluidic channels using fluorescence microscopy, comparing their activity for fluorescein reduction by sodium borohydride. We used first principles calculations to support our conclusion that the rate-limiting step of borohydride oxidation is structure sensitive, with distinct behaviour resulting from the different edge site abundance on the three particle shapes. We highlighted the importance of single nanoparticle resolution to avoid ensemble averaging and to expose both single particle effects and the impact of the variance of these effects on our understanding.

Figure credit: Levin et al., ACS Nano 2022 (ASAP). doi: 10.1021/acsnano.2c06505.