Science Daily March 16, 2022 A team of researchers in the US (North Carolina State University, University of Buffalo) has developed and demonstrated a ‘self-driving lab’ that uses artificial intelligence and fluidic systems to advance our understanding of metal halide perovskite (MHP) nanocrystal using cesium lead halides for proof of concept. The self-driving lab technology can autonomously dope MHP nanocrystals with varying levels of manganese which changes the optical and electronic properties of the nanocrystals and introduces magnetic properties to the material. Thus, giving control over greater range of electronic and magnetic properties. The autonomous system could also be used […]
Tag Archives: Materials science
Simpler graphene method paves way for new era of nanoelectronics
Phys.org March 15, 2022 The high electron mobility of graphene points to great potential for broadband communications and high-speed electronics operating at terahertz switching rates. However, complex, and expensive fabrication methods make it more expensive and hinder mass production of such devices. Researchers in Sweden proposed chemical vapor deposition (CVD) of graphene on commercial copper (Cu) foils providing a scalable route towards high-quality single-layer graphene. The graphene is grown on a metallic surface like Cu, Pt or Ir, after which it can be separated from the metal and transferred to specifically required substrates. The process can be simply explained as […]
Breakthrough in quantum sensing provides new material to make qubits
Phys.org March 9, 2022 Being atomically thin and amenable to external controls, 2D materials offer a new paradigm for the realization of patterned qubit fabrication and operation at room temperature for quantum information sciences applications. An international team of researchers (USA – Temple University, Northeastern University, Taiwan) has shown that the antisite defect in 2D transition metal dichalcogenides (TMDs) can provide a controllable solid-state spin qubit system. Using high-throughput atomistic simulations, they identified several neutral antisite defects in TMDs that lie deep in the bulk band gap and host a paramagnetic triplet ground state. The analysis revealed the presence of […]
Researchers design charged ‘power suits’ for electric vehicles and spacecraft
Phys.org March 7, 2022 A team of researchers in the US (University of Central Florida, NASA Kennedy space Center, FL) has developed a supercapacitor using carbon fiber reinforced polymer (e-CFRP) that can store electrical energy and function as the structural component for the EV’s body shell. Vertically aligned graphene sheets were attached to carbon fiber electrodes on which different metal oxides were deposited to obtain high-energy density electrodes. They fabricated a high-strength multilayer e-CFRP assembly using an alternate layer patterning configuration of epoxy and polyacrylamide gel electrolyte. It delivered a high areal energy density of 0.31 mWh cm–2 at 0.3 […]
Study raises new possibilities for triggering room-temperature superconductivity with light
Phys.org March 9, 2022 In the case of the superconducting material yttrium barium copper oxide, or YBCO, experiments have shown that under certain conditions, knocking it out of equilibrium with a laser pulse allows it to superconduct at much closer to room temperature than researchers expected. YBCO switches from a normal to a superconducting state when chilled below a certain transition temperature or it can be switched off with a pulse of light. An international team of researchers (South Korea, USA – SLAC National Accelerator Laboratory, Japan, Germany) compared the two switching approaches (exposing to high magnetic field and laser […]
Freshwater from thin air
Science Daily February 28, 2022 Hygroscopic materials have attracted widespread attention because of their water harvesting performance. However, the introduction of many inorganic salts often leads to aggregation and leakage issues in practical use. Researchers at UT Austin have developed polyzwitterionic hydrogels as an effective Atmospheric Water Harvesting (AWH) material platform. Via anti-polyelectrolyte effects, the hygroscopic salt coordinated with polymer chains could capture moisture and enhance the swelling property, leading to a strong moisture sorption capacity. The hydrogel showed (0.62 g g−1, 120 minutes for equilibrium at 30 % relative humidity) and produced 5.87 L kg−1 freshwater per day. According to the researchers […]
Lightweight nanofiber mats could battle bullets, deflect space debris
Nanowerk February 28, 2022 The weak nature of van der Waals interactions limits the CNT mats from achieving greater performance. Researchers at the University of Wisconsin have developed an efficient approach to augment the inter-fiber interactions by introducing aramid nanofiber (ANF) links between CNTs, which forms stronger and reconfigurable interfacial hydrogen bonds and π–π stacking interactions, leading to synergistic performance improvement with failure retardation. In experiments under supersonic impacts, strengthened interactions in CNT mats enhanced their specific energy absorption up to 3.6 MJ/kg which outperformed bulk Kevlar-fiber-based protective materials. By modifying the interfacial interactions in the mats by adding Kevlar […]
Strong, stretchy, self-healing polymers rapidly recover from damage
Phys.org February 28, 2022 Previously researchers in Japan synthesized multiblock copolymers that exhibited excellent elasticity and self-healing by using the two-component copolymerization of non-polar ethylene and polar methoxyaryl-substituted propylenes. Now they have developed a three-component ‘terpolymer’ of ethylene and two different methoxyaryl-functionalized propylenes using a scandium catalyst. The long, soft sections form a highly flexible matrix, within which are hard and crystalline sections that rapidly re-aggregate after the material is cut, thereby self-healing any damage within five minutes to recover 99% of its toughness and 97% of its tensile strength. The material could be stretched to almost 14 times its […]
Mechanical metamaterials: Toughness and design criteria
Phys.org February 21, 2022 Rapid progress in additive manufacturing methods has created a new class of ultralight mechanical metamaterials with extreme functional properties. Their application is ultimately limited by their tolerance to damage and defects, but an understanding of this sensitivity has remained elusive. An international team of researchers (UK, USA – Virginia Polytechnical Institute and State University, UCLA, industry) used metamaterial specimens consisting of millions of unit cells, to show that not only is the stress intensity factor, as used in conventional elastic fracture mechanics, insufficient to characterize fracture, but also that conventional fracture testing protocols are inadequate. With […]
Microparticles show ability to turn in reverse, paving the way for microfluidic devices
Nanowerk February 23, 2022 Self-organized vortex of rotating microparticles in a fluid will reverse direction when an electric stimulus is interrupted and then reapplied with the same orientation. A team of researchers in the US (Argonne National Laboratory, Northwestern University) investigated how these collective self-assembled states can be controlled and manipulated, and what would happen when they stopped and then restarted the field fueling the motion of the particles. They found that the particles’ relative positions created a kind of distributed collective memory that caused them to begin to rotate in the opposite direction. They found that this phenomenon was […]