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 […]
Tag Archives: Materials science
Layered superconductor coaxed to show unusual properties with potential for quantum computing
Phys.org July 31, 2024 Chiral superconductors are a unique class of unconventional superconductors in which the complex superconducting order parameter winds clockwise or anticlockwise in the momentum space. It represents a topologically non-trivial system with intrinsic time-reversal symmetry breaking (TRSB) and direct implications for topological quantum computing. Chiral molecules with neither mirror nor inversion symmetry have been widely investigated. An international team of researchers (USA – UCLA, Czech Republic) explored unconventional superconductivity in chiral molecule intercalated TaS2 hybrid superlattices. The experimental signatures of unconventional superconductivity suggested that the intriguing interplay between crystalline atomic layers and the self-assembled chiral molecular layers […]
New nanomaterials could boost hydrogen production for clean energy
Phys.org August 5, 2024 Nanosizing confers unique functions in materials such as graphene and quantum dots. An international team of researchers (UK, China) described two nanoscale-covalent organic frameworks (nano-COFs) that exhibited exceptionally high activity for photocatalytic hydrogen production that resulted from their size and morphology. Compared to bulk analogues, the downsizing of COFs crystals using surfactants provided greatly improved water dispersibility and light-harvesting properties. The nano-COFs showed high hydrogen evolution rate. They observed a reverse concentration-dependent photocatalytic phenomenon where a higher photocatalytic activity was found at a lower catalyst concentration, and the materials showed a molecule-like excitonic nature, a function […]
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 […]
Proton-conducting materials could enable new green energy technologies
MIT News July 23, 2024 A quantitative understanding of the physical traits of a material that regulates proton diffusion is necessary for accelerating the discovery of fast proton conductors which is key for advancing many electrochemical technologies. A team of researchers in the US (MIT, Auburn University, Northwestern University) mapped the structural, chemical and dynamic properties of solid acids to the elementary steps of the Grotthuss mechanism of proton diffusion by combining ab initio molecular dynamics simulations, analysis of phonon spectra and atomic structure calculations. They identified the donor–hydrogen bond lengths and the acidity of polyanion groups as key descriptors […]
High-speed electron camera uncovers new ‘light-twisting’ behavior in ultrathin material
Phys.org July 10, 2024 Manipulating the polarization of light at the nanoscale is key to the development of next-generation optoelectronic devices. This is typically done via waveplates using optically anisotropic crystals, with thicknesses on the order of the wavelength. A team of researchers in the US (Stanford, SLAC Nation Acceleration Laboratory, Harvard University, Columbia University, Florida State University, UCLA) used a novel ultrafast electron-beam-based technique sensitive to transient near fields at THz frequencies to observe a giant anisotropy in the linear optical response in Tungsten ditelluride (WTe2). They demonstrated that it is possible to tune THz polarization using a 50 […]
A new metamaterial concept offering the potential for more efficient data storage
Nanowerk July 16, 2024 Researchers in Germany demonstrated that not just individual bits, but entire bit sequences can be stored in cylindrical domains. They used high perpendicular magnetic anisotropy synthetic antiferromagnets in the form of multilayer-based metamaterials whose antiferromagnetic interlayer exchanged energy was purposefully reduced below the out-of-plane demagnetization energy controlling magnetic domain formation. They demonstrated via macroscopic magnetometry and microscopic Lorentz transmission electron microscopy, that it was possible to stabilize nanometer-scale stripe and bubble textures consisting of ferromagnetic out-of-plane domain cores separated by antiferromagnetic in-plane Bloch-type domain walls. According to the researchers this coexistence of mixed ferromagnetic/antiferromagnetic order on […]
Small steps for electrons—big steps for the future? Ultrafast microscope reveals electron pathways in solar cells
Phys.org July 17, 2024 To understand the transport of photoexcited charge carriers for designing next-generation light-harvesting devices an international team of researchers (Germany, UK) simultaneously probed the intrinsic out-of-plane charge-carrier diffusion and the nanoscale morphology of the organic–inorganic metal halide perovskite FA0.83Cs0.17Pb(I1−xClx)3 by pushing depth-sensitive terahertz near-field nanospectroscopy to extreme subcycle timescales. By analysing deep-subcycle time shifts of the scattered terahertz waveform after photoexcitation, they accessed the vertical charge-carrier dynamics within single grains. At all the measured locations, despite topographic irregularities, diffusion was homogeneous on the 100 nm scale, although it varied between mesoscopic regions. According to the researchers linking in […]
High-selectivity graphene membranes enhance CO₂ capture efficiency
Phys.org July 6, 2024 Although membranes based on a porous two-dimensional selective layer offer the potential to achieve exceptional performance to improve energy efficiency and reduce the cost for carbon capture, competitive sorption of CO2 with the potential to yield high permeance and selectivity has remained elusive. Researchers in Switzerland showed that a simple exposure of ammonia to oxidized single-layer graphene at room temperature incorporates pyridinic nitrogen at the pore edges. This led to a highly competitive but quantitatively reversible binding of CO2 with the pore. A combination of CO2/N2 separation factor and CO2 permeance from a stream containing 20 vol% […]
Scientists develop the next generation of highly efficient memory materials with atom-level control
Phys.org June 27, 2024 Recently a single-phase material concurrently exhibiting magnetism and the spin Hall effect has emerged as a scientifically and technologically interesting platform for realizing efficient and compact spin–orbit torque (SOT) systems. Researchers in South Korea demonstrated external-magnetic-field-free switching of perpendicular magnetization in a single-phase ferromagnetic and spin Hall oxide SrRuO3 by delicately altering the local lattices of the top and bottom surface layers of SrRuO3, while retaining a quasi-homogeneous, single-crystalline nature of the SrRuO3 bulk. This led to unbalanced spin Hall effects between the top and bottom layers. SrRuO3 exhibited the highest SOT efficiency and lowest power […]