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 […]
Tag Archives: Advanced materials
World’s first micromachine twists 2D materials at will
Phys.org August 22, 2024 Two-dimensional materials (2DM) and their heterostructures offer tunable electrical and optical properties, primarily modifiable through electrostatic gating and twisting. Although electrostatic gating is a well-established method for manipulating Two-dimensional materials (2DM), achieving real-time control over interfacial properties remains challenging in exploring 2DM physics and advanced quantum device technology. Current methods are limited in their scope of application, lacking the accessibility and scalability of electrostatic gating at the device level. An international team of researchers (USA – Harvard University, MIT, Stanford University, UC Berkeley, Japan) introduced an on-chip platform for 2DM with in situ adjustable interfacial properties, […]
Printed electronics material can store 1,000 times more charge than current forms
Phys.org August 19, 2024 Making the Internet of Things a reality will require the type of circuitry and advanced operations that are only possible with electronics that can function in both positive and negative voltage modes. Researchers in Canada developed a new material zwitterion composed of an imidazolium tethered to an anionic sulfonyl(trifluoromethane sulfonyl)imide group as an alternative dielectric material to traditional ionic liquids. The zwitterion not only melted below 100 °C but also proved to be nonhygroscopic. By blending this compound with poly(methyl methacrylate) over a range of concentrations and thicknesses, they made high-capacitance organic dielectric materials. Experiments suggested […]
Smart fabrics detect and repel pathogens to prevent hospital infections
Nanowerk August 20, 2024 Healthcare textiles serve as key reservoirs for pathogen proliferation. Researchers in Canada developed a new class of Smart Fabrics (SF) with integrated “Repel, Kill, and Detect” functionalities, which they achieved through a blend of hierarchically structured microparticles, modified nanoparticles, and an acidity-responsive sensor. It showed good resilience against aerosol and droplet-based pathogen transmission, showed a reduction exceeding 99.90% compared to uncoated fabrics across various drug-resistant bacteria. Experiments involving bodily fluids from healthy and infected individuals revealed a significant reduction of 99.88% and 99.79% in clinical urine and feces samples compared to uncoated fabrics. According to the […]
Physicists report new insights into exotic particles key to magnetism
Phys.org August 1, 2024 An international team of researchers (USA – MIT, Arizona State University, Brookhaven National Laboratory, France, the Netherlands) studied the impact of charge transfer and magnetic order on the excitation spectrum of the nickel dihalides. They detected sharp excitations, analogous to the recently reported excitons and demonstrated that the excitons were dispersive using momentum-resolved resonant inelastic X-ray scattering. The data showed a ligand-mediated multiplet dispersion, which was tuned by the charge-transfer gap and independent of the presence of long-range magnetic order. According to the researchers this reveals the mechanisms governing nonlocal interactions of on-site intra-atomic transitions between […]
MIT researchers identify routes to stronger titanium alloys
MIT News July 2, 2024 Optimizing the properties of structural materials to involve a tradeoff between two key characteristics: strength and ductility. Mechanical properties of titanium alloys suffer from the lack of 〈c + a〉dislocations on pyramidal slip planes, failing homogeneous plastic strain accommodation. A team of researchers in the US (MIT, industry) demonstrated that such a dilemma may be overcome by meticulously tuning the c/a ratio, the simplest crystallographic parameter of the hexagonal close-packed lattice, through Sn alloying. Combining this lattice-scale design concept with a cross-rolling based polycrystal-scale design solution, they showed a facile route to bimodal (α + […]
A high-temperature superconductor with zero resistance that exhibits strange metal behavior
Phys.org June 25, 2024 In recent experimental signatures of superconductivity close to 80 K in La3Ni2O7 under pressure, a zero-resistance was not observed. Researchers in China showed that the zero-resistance state does exist in single crystals of La3Ni2O7. They found that the system remained metallic under applied pressures, suggesting the absence of a metal–insulator transition proximate to the superconductivity. Analysis of the normal state T-linear resistance revealed a link between this strange-metal behaviour and superconductivity. This was in line with other classes of unconventional superconductors, including the cuprates and Fe-based superconductors. According to the researchers further investigations exploring the interplay of […]
Researchers develop tuneable anti-counterfeiting material
Phys.org June 24, 2024 Nanosized PersL materials could blend more easily with solvents and allow printing patterns with fine details. MgGeO3 is one of the frequently employed lattice hosts for PersL phosphors. It can accommodate divalent ions such as Mn2+ to produce deep red PersL. To date, the only reported method of synthesizing nanosized Mn-doped MgGeO3 (MGO:Mn) is the sol–gel method. The synthesis product has a wide particle size distribution and suffers severe aggregation. Researchers in Canada synthesized MGO:Mn nanorods with a uniformly distributed morphology. The nanorods exhibit more intense and longer-lasting PersL. By detailed comparative study between the MGO:Mn […]
Researchers discover new flat electronic bands, paving way for advanced quantum materials
Phys.org June 25, 2024 Flat electronic bands expected to show proportionally enhanced electron correlations are being pursued in d-electron-based systems with crystalline lattices that feature destructive electronic interference. Such flat bands are generically located far away from the Fermi energy, which limits their capacity to partake in the low-energy physics. An international team of researchers (USA – Rice University, Stony Brook University, independent organization, Spain, Austria) showed that electron correlations produce emergent flat bands that are pinned to the Fermi energy. They demonstrated this effect within a Hubbard model, in the regime described by Wannier orbitals where an effective Kondo […]
Molecular sponge for the electronics of the future
EurekAlert June 17, 2024 Porous covalent organic frameworks (COFs) enable the realization of functional materials with molecular precision. Past research has typically focused on generating rigid frameworks where structural and optoelectronic properties are static. Constructing dynamic, yet crystalline and robust frameworks require a well-controlled degree of flexibility. An international team of researchers (UK, Germany, USA – Stony Brook University) has developed dynamic 2D COFs that can open and close their pores upon uptake or removal of guests while retaining their crystalline long-range order. The process requires a well-controlled degree of flexibility. They achieved this through a ‘wine rack’ design where […]