MIT News September 24, 2024 There is minimal research on the additive manufacturing (AM) viability to produce structural building components, which could reduce tooling costs and increase flexibility for their production. A team of researchers in the US (MIT, industry) has provided design, manufacturing, and experimental testing to assess the feasibility of using glass AM to produce interlocking masonry units for the construction industry. Their glass 3D printer could print a maximum volume for producing full-size masonry units. They discussed how to adapt design guidelines for glass AM to produce interlocking units, evaluated fabrication ease and structural performance using three […]
Category Archives: Materials science
First liquid-liquid extraction trial finds porous liquids can separate harmful or unwanted alcohols from mixtures
Phys.org September 18, 2024 Researchers in the UK explored the application of porous liquids for the separation of miscible liquids, using MEG/water (MEG=monoethylene glycol) and EtOH/water as proof-of-principle. PLs ZIF-8@PDMS (PL1, PDMS=polydimethylsilicone) or ZIF-8@sesame oil (PL2) each consisting of 25 wt % of the hydrophobic microporous material ZIF-8 was dispersed in PDMS or sesame oil respectively were physically stable to sedimentation. MEG was selectively extracted through a membrane from approximately into the PL phase. The PL could also be regenerated and re-used, suggesting its potential for continuous, cyclic extraction, PL3 (silicalite-1@PDMS) was effective in selective alcohol extraction from beverages. According to […]
High-pressure reactions can turn nonporous rocks into sponges
Phys.org September 23, 2023 An international team of researchers (Switzerland, France, Germany) studied (de)hydration reactions where associated solid density changes were predominantly balanced by porosity changes, with solid rock deformation playing a minor role and proposed a hypothesis for three scenarios of (de)hydration front propagation and test it. The models coupled porous fluid flow, solid rock volumetric deformation, and (de)hydration reactions. Their model validated the hypothesized scenarios and showed that the change in solid density across the reaction boundary dictates whether hydration or dehydration fronts propagate. The models demonstrated that reactions could drive the propagation of (de)hydration fronts, characterized by […]
New material with wavy layers of atoms exhibits unusual superconducting properties
Phys.org September 19, 2024 Bulk van der Waals (vdW) superlattices hosting 2D interfaces between minimally disordered layers represent scalable bulk analogues of artificial vdW heterostructures and present a complementary venue to explore incommensurately modulated 2D states. An international team of researchers in the (USA- MIT, National High Magnetic Field Laboratory, Harvard, Japan) reported the bulk vdW superlattice SrTa2S5 realizing an incommensurate one-dimensional (1D) structural modulation of 2D transition metal dichalcogenide (TMD) H-TaS2 layers. High-quality electronic transport in the H-TaS2 layers was made anisotropic by the modulation and exhibited commensurability oscillations paralleling lithographically modulated 2D systems. They found unconventional, clean-limit superconductivity […]
Researchers observe an antiferromagnetic diode effect in even-layered MnBiâ‚‚Teâ‚„
Phys.org September 22, 2024 Non-centrosymmetric polar conductors are intrinsic diodes that could be of use in the development of nonlinear applications. Such systems have recently been extended to non-centrosymmetric superconductors. An international team of researchers (USA – Harvard University, Northeastern University, MIT, UCLA, Boston College, Taiwan, India, Japan) has reported antiferromagnetic diode effect in a centrosymmetric crystal without directional charge separation. Large second-harmonic transport in a nonlinear electronic device enabled by the compensated antiferromagnetic state of even-layered MnBi2Te4. They showed that this antiferromagnetic diode effect could be used to create in-plane field-effect transistors and microwave-energy-harvesting devices, and electrical sum-frequency generation […]
Composite plastic degrades easily with bacteria, offers environmental benefits
Phys.org September 5, 2024 Researchers in Israel fabricated a biodegradable composite material based on hydroxyethyl cellulose polymer and tyrosine nanocrystals, which demonstrated enhanced strength and ductility superior to most biodegradable plastics. This emergent behavior resulted from an assembly pattern that led to a uniform nanoscale morphology and strong interactions between the components. Water-resistant biodegradable composites encapsulated with hydrophobic polycaprolactone as a protection layer were also fabricated. According to the researchers self-assembly of robust sustainable plastics with emergent properties by using readily available building blocks provides a valuable toolbox for creating sustainable materials… read more. Open Access TECHNICAL ARTICLE
Molecular simulations and supercomputing shed light on energy-saving biomaterials
Phys.org September 6, 2024 Nanocellulose from biomass is promising for manufacturing sustainable composite biomaterials and bioplastics. However, obtaining nanocellulose at pilot scale requires energy-intensive fibrillation to shear cellulose fibers apart into nano-dimensional forms in water. To reduce the energy consumption in fibrillation a team of researchers in the US (Oak Ridge National Laboratory, University of Maine) found that aqueous NaOH:urea (0.007:0.012 wt.%) reduced the fibrillation energy by ~21% on average relative to water alone. The NaOH and urea acted synergistically on CNFs to aid fibrillation but at different length scales. According to the researchers their work suggested a general mechanism […]
Optoelectronic diamond device reveals an unexpected phenomenon reminiscent of lightning in slow motion
Phys.org September 4, 2024 Establishing connections between material impurities and charge transport properties in emerging electronic and quantum materials requires new diagnostic methods tailored to these unique systems. Many such materials host optically-active defect centers which offer a powerful in situ characterization system, but one that typically relies on the weak spin-electric field coupling to measure electronic phenomena. An international team of researchers (Australia, USA – CUNY-The City College of New York) combined charge-state sensitive optical microscopy with photoelectric detection of an array of nitrogen-vacancy (NV) centers to directly image the flow of charge carriers inside a diamond optoelectronic device. […]
Materials scientists develop road map for designing responsive gels with unusual properties
Phys.org August 22, 2024 Metallo-polyelectrolytes are versatile materials for applications like filtration, biomedical devices, and sensors, due to their metal-organic synergy. Their dynamic and reversible electrostatic interactions offer high ionic conductivity, self-healing, and tunable mechanical properties. However, the knowledge gap between molecular-level dynamic bonds and continuum-level material properties persist, largely due to limited fabrication methods and a lack of theoretical design frameworks. To address this gap researchers at Caltech developed a framework, combining theoretical and experimental insights, highlighting the interplay of molecular parameters in governing material properties. Using stereolithography-based additive manufacturing, they produced durable metallo-polyelectrolytes gels with tunable mechanical properties […]
Nontoxic ceramic could replace lead-based electronic components
Phys.org August 24, 2024 Electrostrictors, materials developing mechanical strain proportional to the square of the applied electric field, present many advantages for mechanical actuation as they convert electrical energy into mechanical, but not vice versa. Both high relative permittivity and reliance on Pb as the key component in commercial electrostrictors pose serious practical and health problems. An international team of researchers (Israel, USA – Brown University, Stony Brook University) showed that ZrxCe1-xO2 has low relative permittivity, and electromechanical properties as electrostrictors – longitudinal electrostriction strain coefficient, and relaxation frequency. They showed that the elastic dipoles in ZrxCe1-xO2 are formed only […]