Free-standing nanoparticle superlattice sheets controlled by DNA.
Free-standing nanoparticle superlattices (suspended highly ordered nanoparticle arrays) are ideal for designing metamaterials and nanodevices free of substrate-induced electromagnetic interference. Here, we report on the first DNA-based route towards monolayered free-standing nanoparticle superlattices. In an unconventional way, DNA was used as a 'dry ligand' in a microhole-confined, drying-mediated self-assembly process. Without the requirement of specific Watson-Crick base-pairing, we obtained discrete, free-standing superlattice sheets in which both structure (inter-particle spacings) and functional properties (plasmonic and mechanical) can be rationally controlled by adjusting DNA length. In particular, the edge-to-edge inter-particle spacing for monolayered superlattice sheets can be tuned up to 20 nm, which is a much wider range than has been achieved with alkyl molecular ligands. Our method opens a simple yet efficient avenue towards the assembly of artificial nanoparticle solids in their ultimate thickness limit--a promising step that may enable the integration of free-standing superlattices into solid-state nanodevices.
Cheng
Wenlong
W
Department of Biological & Environmental Engineering, Cornell University, 226 Riley Robb, Ithaca, New York 14853, USA.
Campolongo
Michael J
MJ
Cha
Judy J
JJ
Tan
Shawn J
SJ
Umbach
Christopher C
CC
Muller
David A
DA
Luo
Dan
D
D004247:DNA / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles
D004247:DNA