DNA-silica nanolattices as mechanical metamaterials
Data files
Mar 25, 2024 version files 133.53 MB
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All_Data.zip
133.52 MB
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README.md
2.18 KB
Abstract
Mechanical metamaterials consist of intricate periodic structures made using additive manufacturing techniques. Yet, nanoscale (<10 nm) features cannot be directly printed using these fabrication techniques, although this is the size regime in which enhanced material properties appear. In addition, current additive manufacturing techniques cannot easily combine disparate materials (e.g., soft, biological polymers with hard ceramics) into structural motifs. Here, we show that DNA origami can be used to construct octahedral-based isotropic and anisotropic nanolattices. When coated with a thin silica layer, these nanolattices obtain strength and energy absorption competitive with the best additively manufactured nanolattices. The DNA nanolattices have strut 6 nm diameters and ~50 nm unit cells, which are two orders of magnitude smaller than lithography-based lattices. The silica coating is as thin as ~1.65 nm, which results in enhanced strength. Atom probe tomography confirms the nanoscale distribution of DNA and silica in the octahedral lattice geometry. Finite element modeling (FEM) reveals two dominant failure modes: buckling at lower coating thicknesses and tensile fracture at higher thicknesses. Molecular dynamics (MD) simulations reveal that the DNA delays failure by suppressing buckling within the lattice struts, while the nanoscale silica undergoes a surface buckling mode which contributes to increased strength at large strains.
README: DNA-silica nanolattices as mechanical metamaterials
https://doi.org/10.5061/dryad.g4f4qrfxz
This folder contains all data needed to reproduce the results in the paper titled "DNA-Silica Nanolattices as Mechanical Metamaterials" by Kulikowski and Wang et al. in Matter.
Naming convention:
sample names start with the heading DNAC-###-###, where the first 3 digits correspond to sets of sample preparation conditions and the second 3 digits correspond to sample numbers within those conditions.
For example, DNAC-001-001 and DNAC-001-003 refer to the silica coating of 1.75nm but dispersed on 2 different silicon wafer pieces. The samples themselves should behave the same. DNAC-003-003 refers to a coating of 5.1nm on its 3rd iteration. This is NOT on the same silicon wafer piece as DNAC-001-003. Some files omit the last 3 digits.
Designations are as follows:
DNAC-001-###: 1.75nm coating thickness samples
DNAC-002-###: space filling coating samples
DNAC-003-###: 5.1nm coating thickness samples
DNAC-004-###: 3.1nm coating thickness samples
DNAC-005-###: space filling coating samples (distinct from DNAC-002-### in that a new batch of particles was made)
DNAC-007-###: 1.65nm coating thickness samples
DNAC-008-###: 2.1 coating thickness samples
DNAC-ESO-###: elongated octahedral structure
DNAC-FSO-### flattended octahedral structure
There are subfolders:
Shell thickness images - images used to find the shell thickness results
RAW data - mechanical data for each test used in the analysis, note that mechanical data from DNAC-001-### through DNAC-005-### are gathered from in-situ SEM testing while DNAC-007-###, DNAC-008-###, DNAC-ESO-###, and DNAC-FSO-### are gather on a benchtop nanoindenter.
- Side depth cells marked N/A are for cubes which have equal depth and length
- Offset yield stresses or energy absorption marked N/A indicate that either the tests were not performed for long enough to determine these values or there are no associated videos so a point of first fracture cannot be determined.
Simulations - simulation data for FEM and MD results in figure 5 of the main manuscript.