Extraordinarily strong, lightweight material combines DNA and glass

Nanowerk  July 25, 2023 Continuous nanolattices are an emerging class of mechanical metamaterials that are highly attractive due to their superior strength-to-weight ratios, which originate from their spatial architectures and nanoscale-sized elements possessing near-theoretical strength. Rational design of frameworks remains challenging below 50 nm because of limited methods to arrange small elements into complex architectures. A team of researchers in the US (Columbia University, Brookhaven National Laboratory, University of Connecticut) fabricated silica frameworks with ∼4- to 20-nm-thick elements using self-assembly and silica templating of DNA origami nanolattices and performed in situ micro-compression testing to examine the mechanical properties. They observed […]

Printing atom by atom

Nanowerk  May 22, 2023 The constantly shrinking critical dimension in state-of-the-art technologies requires fabrication of complex conductive structures with nanometer resolution. Electrochemical techniques can produce impurity-free metallic conductors with superb electrical and mechanical properties, however, true nanoscale resolution (<100 nm) remained unattainable. An international team of researchers (Switzerland, Singapore) employed nozzles with dimensions as small as 1 nm to demonstrate layer-by-layer manufacturing of 25 nm diameter voxels. Full control of the printing process allowed adjustment of the feature size on-the-fly, printing tilted, and overhanging structures. Based on experimental evidence, they estimated the limits of electrochemical 3D printing and discussed the […]

Researchers 3D print high-performance nanostructured alloy that’s both ultrastrong and ductile

Science Daily  August 3, 2022 The additive manufacture of metal alloys by laser powder bed fusion (L-PBF) involves large temperature gradients and rapid cooling which enables microstructural refinement at the nanoscale to achieve high strength. However, high-strength nanostructured alloys produced by laser additive manufacturing often have limited ductility. A team of researchers in the US (UMass Amherst, Georgia Institute of Technology, Texas A&M, Oak Ridge National Laboratory, Rice University, Lawrence Livermore National Laboratory, UCLA) used L-PBF to print dual-phase nanolamellar high-entropy alloys (HEAs) of AlCoCrFeNi that exhibit a combination of a high yield strength of about 1.3 gigapascals and a large […]

Researchers fabricate complex optical components from fluids

Nanowerk  November 18, 2021 Based on controlling the minimum energy state of the interface between a curable optical liquid and an immersion liquid and dictating a geometrical boundary constraint a team of researchers in Israel has developed a method to shape liquid volumes and solidify them into desired freeform components. They provided an analytical solution for the resulting topography given a predefined boundary and demonstrated the fabrication of freeform components with sub-nanometer surface roughness within minutes. The process allows for rapid prototyping of high-quality components, has the potential to answer an unmet need in the optical design industry and allowing […]

Engineers invent ultra-fast manufacturing technology

Nanowerk  November 3, 2021 Current printing techniques for printing soft electronics (PSE) are still facing long-lasting challenges in addressing the conflict between printing speed and performance. A team of researchers in the US (California Polytechnic State University, UC San Diego, University of South Florida, Carnegie Mellon University) has developed a new corona-enabled electrostatic printing (CEP) technique for ultra-fast roll-to-roll (R2R) manufacturing of binder-free multifunctional e-skins. CEP-printed graphene e-skins were demonstrated to possess an outstanding strain sensing performance. The binder-free feature of the CEP-assembled networks enables them to provide pressure sensitivity as low as 2.5 Pa and capability to detect acoustic […]

With a zap of light, system switches objects’ colors and patterns

MIT News  May 4, 2021 Researchers at MIT have developed a way to rapidly update imagery on object surfaces. The system, dubbed “ChromoUpdate” pairs UV light projector with items coated in light-activated dye. The projected light alters the reflective properties of the dye, creating colorful new images in just a few minutes. ChromoUpdate is a texture transfer system for fast design iteration. For the early stages of design, it provides a fast grayscale preview that enables a texture to be transferred in under one minute. Once designers are satisfied with the grayscale texture ChromoUpdate supports designers in coloring the texture by […]

Nanosheet-based electronics could be one drop away

Nanowerk  January 8, 2021 Researchers in Japan overcame the “coffee ring” effect of drop casting by controlled convection using a pipette and a hotplate. They found that dropping a solution containing 2D nanosheets with a simple pipette onto a substrate heated on a hotplate to a temperature of about 100°C, followed by removal of the solution, causes the nanosheets to come together in about 30 seconds to form a tile-like layer. They demonstrated controlled thermal convection by depositing particle solutions of titanium dioxide, calcium niobate, ruthenium oxide, and graphene oxide. They also tried different sizes and shapes of a variety […]

On-surface synthesis of graphene nanoribbons could advance quantum devices

Nanowerk  October 26, 2020 The lack of atomic-scale precision in using current state-of-the-art “top-down” synthetic methods — cutting a graphene sheet into atom-narrow strips – stymie graphene’s practical use. An international team of researchers (USA – Oak Ridge National Laboratory, The University of Tennessee, Poland, Luxembourg) has developed a “bottom-up” approach — building the graphene nanoribbon directly at the atomic level in such a way that it can be used in specific applications. The nanoribbons were synthesized on the surface of rutile titanium dioxide that assisted the cyclode-hydrofluorination of specifically designed precursor molecules through a series of thermally triggered transformations. […]

‘Like a fishing net,’ nanonet collapses to trap drug molecules

Science Daily  October 5, 2020 Natural biomolecules such as peptides and DNA can dynamically self-organize into diverse hierarchical structures. Researchers at the Northwestern University have reported both experiments and simulations on the dynamic network self-assembly and subsequent collapse of the synthetic homopolymer poly(propylene sulfone). The assembly is directed by dynamic noncovalent sulfone–sulfone bonds that are susceptible to solvent polarity. The hydration history controls the homopolymer assembly into uniform nanostructured hydrogels of spherical, vesicular, or cylindrical morphologies. The electrostatic hydrogels achieve >95% encapsulation efficiency for hydrophilic small molecules and biologics. This system validates sulfone–sulfone bonding for dynamic self-assembly, presenting a robust […]

Researchers breaking new ground in materials science

Science Daily  May 20, 2020 An international team of researchers (Canada, Italy) demonstrated the fabrication of mesoscale ordered two-dimensional π-conjugated polymer kagome lattices with semiconducting properties. To make the material they combined a rigid azatriangulene precursor and a hot dosing approach, which favours molecular diffusion and eliminates voids in the network. These results open opportunities for the synthesis of two-dimensional π-conjugated polymer Dirac cone materials and their integration into devices. The integration of this system into a device (e.g. transistors) may lead to outstanding performances. The results will foster more studies on a wide range of two-dimensional conjugated polymers with […]