Northwestern University
chadnano@northwestern.eduMirkin Research Group
CBES Research Areas:
Autonomous Soft Microrobots, Hierarchical Structure-Mediated Photocatalysis
Northwestern University
chadnano@northwestern.eduCBES Research Areas:
Autonomous Soft Microrobots, Hierarchical Structure-Mediated Photocatalysis
The Mirkin group is interested in bio-inspired, ordered materials prepared via crystal engineering with DNA with capabilities for plasmon-enhanced photocatalysis. Recently, the Mirkin group discovered the clathrate lattice, the most structurally complex nanoparticle-based material to date. The cages in natural clathrates are formed when molecular or atomic nodes adopt discrete bond angles between 100° and 125°. To assemble the nanoparticle analog, oblate trigonal bipyramids were identified as ideal building blocks as they promote the formation of DNA bonds with a ~110° bond angle. The cavities in the clathrate crystals have potential for host-guest recognition applications as well as catalysis. Mirkin is exploring the cavities of these clathrates as candidates for photocatalysis of water splitting, CO2 reduction, and N2 fixation. In these structures, the sharp tips of the DNA-functionalized Au bipyramids are directed into cavities with sizes on the order of visible light wavelengths. The cavities interact strongly with light and induce an electromagnetic field inside the voids, which promotes charge-separated states that are critical for photocatalysis.
The Mirkin group is also constructing magnetic membranes with built-in heterogeneities through the assembly of magnetic nanoparticles densely functionalized with DNA film superlattices of specific shapes analogous to bulk superlattices and crystal habits. The nanoparticle core can be interchanged with many different compositions, sizes, and shapes. Magnetic programmable atom equivalents are assembled onto a surface functionalized with DNA in a layer-by-layer fashion to install heterogeneity between layers or laterally across the thin film.
pH-Responsive Nanoparticle Superlattices with Tunable DNA Bonds
Zhu, J., Kim, Y., Lin, H., Wang, S., Mirkin, C.A.
J. Am. Chem. Soc. 140, 2018, 5061-5064.
Clathrate Colloidal Crystals
Lin, H., Lee, S., Sun, L., Spellings, M., Engel, M., Glotzer, S.C., Mirkin, C.A.
Science 355, 2017, 931-935.
See all CBES publications authored by Chad Mirkin