Phys.org June 26, 2024 The current concrete carbonation approaches are hindered by low CO2 capture efficiency and high energy consumption, often resulting in weakened concrete. An international team of researchers (USA – Northwestern University, Switzerland) experimentally explored a carbonation approach that resorts to injecting CO2 into a cement suspension subsequently used to manufacture concrete, turning the carbonation reaction into an aqueous ionic reaction with a very fast kinetics compared to traditional diffusion-controlled approaches. This approach achieved a CO2 sequestration efficiency of up to 45% and maintained an uncompromised concrete strength. The study showed that the CO2 injection rate influenced the […]
Tag Archives: Materials science
Researchers create new class of materials called ‘glassy gels’
Phys.org June 19, 2024 By swelling with solvent, glassy polymers can become gels that are soft and weak yet have enhanced extensibility. The marked changes in properties arise from the solvent increasing free volume between chains while weakening polymer–polymer interactions. A team of researchers in the US (North Carolina State University, University of Nebraska) developed a unique class of materials called glassy gels with desirable properties of both glasses and gels by solvating polar polymers with ionic liquids at appropriate concentrations. The ionic liquid increases free volume and extensibility despite the absence of conventional solvent. It forms strong and abundant […]
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 […]
Space radiation can damage satellites—next-generation material could self-heal when exposed to cosmic rays
Phys.org June 24, 2024 Perovskite photovoltaics have been shown to recover, or heal, after radiation damage. A team of researchers in the US (National Renewable Energy Laboratory (NREL), Rochester Institute of Technology, North Texas University, University of North Carolina, NASA Glenn Research Center, Cleveland, OH, University of Oklahoma, University of Buffalo) deconvolved the effects of radiation based on different energy loss mechanisms from incident protons which induce defects or can promote efficiency recovery. They designed a dual dose experiment first exposed devices to low-energy protons efficient in creating atomic displacements and then irradiated with high-energy protons that interacted differently. Correlated […]
Stacking three layers of graphene with a twist speeds up electrochemical reactions
Phys.org June 21, 2024 A team of researchers in the US (University of Michigan, SLAC National Accelerator Laboratory, Carnegie Mellon University, MIT) developed a twist-dependent electrochemical activity map, combining a low-energy continuum electronic structure model with modified Marcus–Hush–Chidsey kinetics in Tri layer graphene. They identified a counterintuitive rate enhancement region spanning the magic angle curve and incommensurate twists in the system geometry. They found a broad activity peak with a ruthenium hexamine redox coupled in regions corresponding to both magic angles and incommensurate angles, a result qualitatively distinct from the twisted bilayer case. According to the researchers flat bands and […]
Making ferromagnets ready for ultra-fast communication and computation technology
Phys.org June 14, 2024 Spin-torque driven critical spin dynamics, such as auto-oscillations, play the central role in many spin-based technologies. An international team of researchers (USA – UC Riverside, Johns Hopkins University, Germany, India, Ukraine) developed the theoretical framework of precessional auto-oscillations for ferromagnets with spin inertia. They discovered and introduced the concept of nutational auto-oscillations and demonstrated that they can become pivotal for future ultrahigh frequency technologies. They showed parallels between spin dynamics in ferrimagnets and inertial ferromagnets and derived an isomorphism that established a foundation for synergistic knowledge transfer between these research fields… read more. TECHNICAL ARTICLE
Nanosized blocks spontaneously assemble in water to create tiny floating checkerboards
Phys.org June 13, 2024 Checkerboard lattices—where the resulting structure is open, porous, and highly symmetric—are difficult to create by self-assembly. Synthetic systems that adopt such structures typically rely on shape complementarity and site-specific chemical interactions that are only available to biomolecular systems (e.g., protein, DNA). A team of researchers in the US (University of California at San Diego, Duke University) demonstrated the assembly of checkerboard lattices from colloidal nanocrystals that harnessed the effects of multiple, coupled physical forces at disparate length scales and that did not rely on chemical binding. Colloidal Ag nanocubes were bi-functionalized with mixtures of hydrophilic and […]
Physicists discover a new optical property that measures the twist in tiny helicesÂ
Phys.org June 17, 2024 Biomimetic nanotechnology and self-assembly advances need chirality. There is a need to develop general methods to characterize chiral building blocks at the nanoscale in liquids such as water. An international team of researchers (UK, Italy, USA – University of Nebraska, Pennsylvania State University) observed chiroptical second-harmonic Tyndall scattering effect in high-refractive-index dielectric nanomaterial Si nanohelices. They provided a theoretical analysis that explained the origin of the effect and its direction dependence, resulting from different specific contributions of “electric dipole–magnetic dipole” and “electric dipole–electric quadrupole” coupling tensors. They narrowed down the number of such terms to 8 […]
New method optimizes lithium extraction from seawater and groundwater
Phys.org June 8, 2024 Understanding how particle features influence Li and sodium (Na) co-intercalation is crucial for system design and enhancing Li selectivity. A team of researchers in the US (University of Chicago, Illinois Institute of Technology, Argonne National Laboratory, University of New York at Buffalo) investigated a series of FePO4 particles with various features and revealed the importance of harnessing kinetic and chemo-mechanical barrier difference between lithiation and sodiation to promote selectivity. The thermodynamic preference of FePO4 provided baseline of selectivity while the particle features were critical to induce different kinetic pathways and barriers, resulting in different Li to […]