Science Daily February 6, 2020 Current methods for placing nano-sized semiconductors on metallic particles to utilize them in nano-lasing and nano-lithography lack precision or are too costly. Researchers in Japan have developed a method based on a hydrothermal synthesis reaction to locally and selectively synthesize zinc oxide in a plasmonic nanoantenna. They first made evident the role of localized surface plasmon resonances (LSPR) for achieving efficient heating of gold nanostructures. Then, by selectively addressing one of the LSPRs of a gold antenna, they demonstrated that localized zinc oxide formation at the targeted location of the antenna can be achieved due […]
Tag Archives: Advanced manufacturing
A megalibrary of nanoparticles
Nanowerk January 23, 2020 There is a lot of interest in the world of nanoscience in making nanoparticles that combine several different materials. But the current process is complex, long and time consuming. Researchers at the Pennsylvania State University have developed two design guidelines, based on interfacial reactivity and crystal structure relations that enable the rational synthesis of a heterostructured nanorod megalibrary. They defined synthetically feasible pathways to 65,520 distinct multicomponent metal sulfide nanorods having as many as 6 materials, 8 segments, and 11 internal interfaces by applying up to seven sequential cation-exchange reactions to copper sulfide nanorod precursors. They […]
Carbon nanotube film produces aerospace-grade composites with no need for huge ovens or autoclaves.
MIT News January 13, 2020 A team of researchers in the US (MIT, industry) utilized a nanomaterial with morphology‐controlled nanoscale capillaries to manufacture aerospace‐grade advanced carbon fiber composites without utilizing pressure from an autoclave. They demonstrated that the capillary pressure from a nanoporous film replaces the need for applied pressure to manufacture void‐free layered polymeric architectures. The nanomaterial‐enabled capillary pressure is quantified as 50% greater than typical pressures used in such processing. The technique may help to speed up the manufacturing of airplanes and other large, high-performance composite structures, such as blades for wind turbines…read more. TECHNICAL ARTICLE
Scientists find new way to sustainably make chemicals by copying nature’s tricks
EurekAlert January 6, 2020 Plants and microorganisms naturally biosynthesize chemicals that often are converted into derivatives with reduced toxicity or enhanced solubility. As a proof of principle, researchers in the UK used genetic engineering to program E. coli and cyanobacteria to make 1-octanol, a chemical currently used in perfumes, which is toxic to the bacteria. They then added an extra set of instructions to E. coli so it would produce two different derivatives of 1-octanol that are both less harmful. The researchers say if this were to be scaled up for industrial systems the engineered bacteria would produce the non-toxic […]
Using a material’s ‘memory’ to encode unique physical properties
Science Daily December 20, 2019 A team of researchers in the US (University of Chicago, University of Pennsylvania) has shown that aging encodes a memory of the stresses imposed during preparation. Because of inhomogeneous local stresses, the material itself decides how to evolve by modifying stressed regions differently from those under less stress. Because material evolution occurs in response to stresses, aging can be “directed” to produce sought-after responses and unusual functionalities that do not inherently exist. Aging obeys a natural “greedy algorithm” as, at each instant, the material simply follows the path of most rapid and accessible relaxation. Their […]
AI learns to design
Science Daily November 6, 2019 A team of researchers in the US (Carnegie Mellon University, Pennsylvania State University) has implemented a two-step framework that learns to imitate human design strategies from observation to generate designs without any explicit information about objective and performance metrics. It is trained to imitate a set of human designers by observing their design state sequences without inducing problem-specific modeling bias or extra information about the problem. It is designed to interact with the problem through a visual interface as humans did when solving the problem. The designs generated by a computational team of these agents […]
Light-based ‘tractor beam’ assembles materials at the nanoscale
Nanowerk November 4, 2019 A team of researchers in the US (University of Washington, Pacific Northwest National Laboratory) adapted optical tweezers which act as a light-based “tractor beam” that can assemble nanoscale semiconductor materials precisely into larger structures. They demonstrated the technique by assembling a heterostructure starting with shorter nanorods of crystalline germanium and capped each with a metallic bismuth nanocrystal. As all the components are suspended in solution the size and shape of the nanostructure can be controlled as it is assembled. The process is repeated to assemble the structure to desired size. They believe that this nanosoldering approach […]
New metamaterial morphs into new shapes, taking on new properties
Science Daily September 11, 2019 Most reconfigurable materials can toggle between two distinct states and require a persistent external stimulus to change from one shape to another and stay that way. Using two-photon lithography a team of researchers in the US (Caltech, GeorgiaTech) designed a silicon-coated lattice with microscale straight beams that bend into curves under electrochemical stimulation, taking on unique mechanical and vibrational properties. They built in defects in the architected material system, based on a pre-arranged design. The material has potential for energy storage systems, provides a novel pathway for development of next generation smart batteries with both […]
In a Totally Unexpected Finding, Water Has Spontaneously Produced Hydrogen Peroxide
Science Alert September 1, 2019 According to the researchers at Stanford University the spontaneous production of hydrogen peroxide can occur when water is atomised into microdroplets without any chemical reagent, catalyst, applied electric potential, or radiation. Hydrogen peroxide production yield was inversely proportional to microdroplet size. The discovery could lead to new and more environmentally sustainable ways of manufacturing this common chemical and innovative opportunities including green and inexpensive production of hydrogen peroxide, green chemical synthesis, safe cleaning, and food processing…read more. TECHNICAL ARTICLE
Ultrathin 3-D-printed films convert energy of one form into another
MIT News August 28, 2019 Piezoelectric materials produce a voltage in response to physical strain, and they respond to a voltage by physically deforming. Researchers at MIT developed an additive fabrication method to 3-D print ceramic transducers about 100 nanometers thin at room temperature. The films resonate at around 5 gigahertz, which is high enough for high-performance biosensors. The raw material used in 3-D printing — contains zinc oxide nanoparticles mixed with some inert solvents, which forms into a piezoelectric material when printed onto a substrate and dried. The researchers are currently working with colleagues to make piezoelectric biosensors to […]