Nanowerk December 23, 2024 3D buckling makes stretchability possible in devices but, when applied to piezoelectric devices due to the uneven distribution of internal strain during deformation. When strains with opposite directions simultaneously affect piezoelectric materials, the electric output can decrease due to cancellation. Researchers in the Republic of Korea developed an electrode design tailored to the direction of strain and a circuit configuration that prevented electric output cancellation. These designs provided stretchability to piezoelectric nanogenerators (PENGs) and minimized electric output loss. Using an inorganic piezoelectric material with a high piezoelectric coefficient, they demonstrated the dynamics of energy harvesting. In […]
Tag Archives: S&T Republic of Korea
Exploring new liquid organic hydrogen carrier materials for a safer, more transportable energy source
Phys.org November 22, 2024 Liquid organic hydrogen carrier (LOHC) materials play a crucial role in hydrogen storage capacity, reaction kinetics, reaction temperature, and reversibility. However, the development and optimization of LOHC materials is limited due to the use of mass-produced materials for bulk hydrogen logistics. Researchers in the Republic of Korea proposed a molecular engineering approach to overcome the limitations of commercial dibenzyltoluene (DBT)-based LOHC systems which have superior physical properties, low price, and low toxicity. They used a new chemical structure, benzyl-methylbenzyl-benzene (BMB) to overcome the limitations of slow reaction kinetics and analyzed the dehydrogenation/hydrogenation pathways. They proposed a […]
Enormous cache of rare earth elements hidden inside coal ash waste, study suggests
Phys.org November 19, 2024 The renewable energy industry is heavily reliant on rare earth elements. A team of researchers in the US (UT Austin, University of Kentucky, University of Wyoming, industry) estimated coal ash resources and potential for extraction of rare earth elements using data for the US. According to the data ~ 52 gigatons (Gt) of coal was produced in the US (1950–2021). Power plants account for most of the coal use. About 70% of coal ash was potentially accessible for rare earth element extraction (1985–2021) and was disposed in landfills and ponds with the remaining coal ash was used […]
Light-matter interaction reveals new paradigm of quantum information technology
Phys.org November 19, 2024 Researchers in the Republic of Korea investigated Coulomb exchange between distinct electron–hole modes and Floquet states, in two-dimensional semiconductors through a theoretical description of time-resolved and angle-resolved photoemission spectroscopy (tr-ARPES) in an extended Haldane model that included the electron–hole Coulomb interaction. Two branches of novel quantum states were found in the form of bosonic exciton–Floquet composites, which resulted from exchange coupling due to the Coulomb interaction. tr-ARPES could be directly employed for the density matrix element of the biparticle subsystem of photoelectron and hole, and electron–hole entanglement and information could be further explored. According to the […]
Novel visible light communication encryption technology uses chiral nanoparticles
Phys.org October 10,2024 Although recent advancements have been made in active emission or passive conversion of polarized light through solution-processed nanomaterials or metasurfaces, the design paths usually encounter limitations. To address these challenges researchers in the Republic of Korea integrated the spatiotemporal modulation of the LED device, the precise control and efficient polarization emission, and the programmable patterning/positioning using 3D printing. They showed high degree of polarization for both linearly and circularly polarized emission from ultrathin inorganic nanowires and quantum nanorods due to the shear-force-induced alignment effect during the protruding of printing filaments. Real-time polarization modulation was obtained through the […]
Chemists use light to replace an oxygen atom with a nitrogen atom in a molecule
Phys.org October 7, 2024 The identity of a heteroatom within an aromatic ring influences the chemical properties of that heterocyclic compound. Chemists have recently introduced a flurry of editing methods to excise individual atoms from molecular frameworks and, in some cases, replace them with alternate functionality. However, systematically evaluating the effect of a single atom poses synthetic challenges, primarily because of thermodynamic mismatches in atomic exchange processes. Researchers in the Republic of Korea developed a photocatalytic strategy that swaps an oxygen atom of furan with a nitrogen group, directly converting the furan into a pyrrole analog in a single intermolecular […]
Restoring quantum dot solar cells as if ‘flattening crumpled paper’
Nanowerk October 4, 2024 All-inorganic CsPbI3 perovskite quantum dots (PQDs) hold significant potential for next-generation photovoltaics due to their unique optoelectronic properties. Initially used long-chain ligands in PQDs synthesis stabilized the black phase but hindered charge transport when employed to solar cells, necessitating their replacement with shorter ones leading to the formation of surface defects and loss of tensile strain, resulting in the transition to the undesired orthorhombic phase and compromising PQD solar cell performance. To address these issues researchers at the Republic of Korea developed an efficient ligand-exchange process utilizing a multifaceted anchoring ligand, 2-thiophenemethylammonium iodide (ThMAI). The larger […]