Columbia Engineering researchers have created engineered 3D nanoparticle materials that can withstand vacuum, high temperatures, high pressures and high radiation. This new manufacturing process leads to the creation of robust and fully engineered nanoscale scaffolds that not only can accommodate various functional types of nanoparticles, but can also be quickly processed using traditional nanotechnology methods.
These self-assembling nanoparticle materials are so stable they can fly in space. Scientists were able to transform the three-dimensional architecture of DNA nanoparticles from a liquid to a solid state, where silicon dioxide strengthens the DNA structures. This new material fully retains its original framework architecture of the DNA nanoparticle lattice. This allowed scientists to study for the first time how these nanomaterials can fight harsh conditions, how they are formed and what their properties are.
Materials differ at the nanoscale, and researchers have long been studying how to use these tiny materials – 1,000 to 10,000 times thinner than a human hair – in everything from making sensors for phones to making faster chips for laptops. However, the fabrication methods were complex when realizing 3D nanoarchitectures. DNA nanotechnology makes it possible to create complexly organized materials from nanoparticles by self-assembly, but given the soft and environmentally dependent nature of DNA, such materials can only be stable under a narrow range of conditions. In contrast, newly formed materials can now be used in a wide range of applications where these engineering designs are required. While traditional nanofabrication is excellent for creating planar structures, the new technique is making it possible to fabricate three-dimensional nanomaterials that are becoming essential for many electronic, optical and energy applications.
The new study demonstrates an efficient method for transforming three-dimensional lattices of DNA nanoparticles into copies of silica, while maintaining the topology of interparticle bonds due to DNA structures and the integrity of the organization of the nanoparticles. Silica works well because it helps preserve the nanostructure of the parent DNA lattice, forms a strong structure, and does not affect the arrangement of nanoparticles.
“DNA in such lattices acquires the properties of silica. It becomes stable in air and can be dried, enabling 3D nanoscale material analysis in real space for the first time. In addition, silica provides strength and chemical stability, it is inexpensive and can be modified as needed, a convenient material.”
Aaron Michelson, Columbia Engineering.
To learn more about the properties of their nanostructures, the team exposed the silica-transformed DNA nanoparticle lattices to extreme conditions: high temperatures above 10,000 ° C and high mechanical stresses in excess of 8 GPa (about 80,000 times atmospheric pressure or 80 times more than in the deepest part of the ocean – the Mariana Trench), and studied these processes on the spot. To assess the viability of the structures for use and further processing steps, the researchers also exposed them to high doses of radiation and focused ion beams.
“Our analysis of the applicability of these structures, combined with traditional nanomaterial manufacturing techniques, demonstrates a truly robust platform for creating elastic nanomaterials using DNA-based approaches to discover their new properties. This is a big step forward as these special properties mean that we can use our 3D nanomaterial assembly and still have access to the full range of processing steps for conventional materials. This integration of new and traditional nano-manufacturing methods is essential for advances in mechanics and electronics, plasmonics, photonics, superconductivity and energetic materials.”
Oleg Gang, professor of chemical engineering, applied physics and materials science
Computers have been made from silicon for over 40 years. It took 40 years to bring the production of planar structures and devices down to about 10 nm. Now we can make and assemble nanoobjects in a test tube in a couple of hours without expensive tools. Eight billion compounds on a single lattice can now be organized to self-assemble using nano-sized processes that we can design. Each connection can be a transistor, a sensor, or an optical emitter – each of which can be a stored data bit. While Moore’s Law is slowing down, DNA assembly programmability is approaching zero to propel us forward in solving problems in new materials and nanofabrication. While this was extremely difficult for current methods, it is extremely important for new technologies.
