Phys.org December 29, 2022 Current water purification technology shows slow adsorption of micropollutants and requires an energy-intensive process for VOCs removal. Researchers in South Korea have developed an efficient molecularly engineered covalent triazine framework (CTF) for rapid adsorption of micropollutants and VOC-intercepting performance using solar distillation. Supramolecular design and mild oxidation of CTFs (CTF-OXs) enabled hydrophilic internal channels and improve molecular sieving of micropollutants. CTF-OX showed rapid removal efficiency of micropollutants (>99.9% in 10 s) and it could be regenerated several times without performance loss. Uptake rates of selected micropollutants were high. Photothermal composite membrane fabrication using CTF-OX exhibited high […]
Tag Archives: S&T South Korea
Speeding up DNA computation with liquid droplets
Nanowerk October 22, 2022 Bottom-up engineering of synthetic condensates advances our understanding of the organizing principle of condensates. It also enables the synthesis of artificial systems with novel functions. However, building synthetic condensates with a predictable organization and function remains challenging. Researchers in South Korea used DNA as a building block to create synthetic condensates that are assembled through phase separation. The programmability of intermolecular interactions between DNA molecules enabled the control over various condensate properties including assembly, composition, and function. Similar to the way intracellular condensates are organized, DNA clients were selectively partitioned into cognate condensates. They demonstrated how […]
The battery that runs 630 km on a single charge
Science Daily October 6, 2022 Anode-free Li metal batteries can increase energy density beyond that of standard lithium-ion batteries. The absence of Li reservoir generates unwarranted volume expansion, permitting electrolyte depletion and rapid cathode capacity consumption. To address this issue researchers in South Korea developed an anode-free Li metal battery with an ion-conductive layer coated with Cu current collector Ag/L in typical carbonate-based electrolytes. The ion-conducting layer causes stable solid electrolyte interphase development and allows for minimal volume expansion when utilizing stable Li hosts. Via density functional theory calculation and experimental measurements and analysis, they demonstrated the beneficial effect of […]
Silicon nanopillars for quantum communication
Science Daily September 20, 2022 The integration of recently discovered single-photon emitters in silicon into photonic structures is advantageous to exploit their full potential for integrated photonic quantum technologies. Researchers in South Korea have developed a top-down nanofabrication method, enabling the production of thousands of nanopillars per square millimeter with state-of-the-art photonic-circuit pitch, all the while being free of fabrication-related radiation damage defects. They found a waveguiding effect of the 1278 nm-G center emission along individual pillars accompanied by improved brightness compared to that of bulk silicon. Their results unlock clear pathways to monolithically integrating single-photon emitters into a photonic platform […]
Researchers use infrared light to wirelessly transmit power over 30 meters
Science Daily August 30, 2022 Researchers in South Korea used an erbium-doped fiber amplifier optical power source with a central wavelength of 1550 nm. and wavelength division multiplexing filter that created a narrowband beam with optical power within the safety limits for free space propagation. They optimized distributed laser charging which enables self-alignment without tracking processes and automatically shifts to a safe low power delivery mode if an object or a person blocks the line of sight. They incorporated a spherical ball lens retroreflector in the receiver unit to facilitate 360-degree transmitter-receiver alignment, which maximized the power transfer efficiency. The […]
Damage-reporting and self-healing skin-like polymeric coatings
Nanowerk August 24, 2022 As it is difficult to determine whether the currently used polymeric coatings applied to the surfaces of automobiles, ships, etc. to protect them from the external environment are already damaged or not, these non-reusable coatings must be regularly replaced, leading to a large amount of waste generation and high disposal costs. Researchers in South Korea have demonstrated mechanochromic and thermally reprocessable thermosets that can be used for autonomic damage reporting and self-healing coatings. A mechanochromic molecule, spiropyran (SP), was covalently incorporated into thermoreversible Diels–Alder (DA) cross-linking networks. Mechanical activation of SPs in DA networks was confirmed […]
Protective coating material self-heals in 30 minutes when exposed to sunlight
Phys.org August 8, 2022 Previous studies using photothermal dyes were mainly based on inorganic materials that are difficult to apply industrially as the coating material should be transparent. In addition, inorganic materials require a large amount of light energy to produce a photothermal effect. Researchers in South Korea developed a new material by adding a dynamic chemical bond that can repeat the decomposition and recombination of the polymer structure and mixed it with a transparent photothermal dye that can absorb near-infrared light which accounts for less than 10% of midday sunlight. This circumvents excessive increase of the vehicle surface temperature. […]
Hearing better with skin than ears
Science Daily July 1, 2022 Previously reported wearable sensors for smart human–machine interaction have limited sound-sensing quality as a consequence of a poor frequency response and a narrow acoustic-pressure range. Researchers in South Korea have developed a skin-attachable acoustic sensor that has higher sensing accuracy in wider auditory field than human ears, with flat frequency response (15–10 000 Hz) and a good range of linearity (29–134 dBSPL) as well as high conformality to flexible surfaces and human skin. They exploited the low residual stress and high processability of polymer materials in a diaphragm structure designed using acousto-mechano-electric modeling to achieve the […]
Optimizing the Sensitivity of Biological Particle Detectors through Atmospheric Particle Analysis According to Climatic Characteristics in South Korea
Sensors 2022, 22(9), 3374 March 31, 2022 Researchers in South Korea optimized an environmentally adaptive detection algorithm that can better reflect changes in the complex South Korean environment than the current models. The algorithm distinguished between normal and biological particles using a laser-induced fluorescence-based biological particle detector capable of real-time measurements and size classification. It operates with minimal false alarms in any environment by training based on experimental data acquired from an area where rainfall, snow, fog and mist, Asian dust, and water waves on the beach occur. The detection performance for each level of sensitivity was examined to enable […]
Uncovering the key to safer energy storage devices that avoid thermal runaway
Phys.org May 9, 2022 Researchers in South Korea investigated the thermal properties of electric double-layer capacitors (EDLCs) for a technical foundation in thermal measurement and revealed significant information. The reversible entropy and free energy changes in the EDLCs caused dynamic changes in the effective heat capacity of the electrodes, which were monitored in real-time during charge and discharge operations. In an EDLC with a 6 M KOH electrolyte, the effective heat capacities of the positive and negative electrodes with a varying voltage from 0 to 1 V were estimated to decrease by approximately 9.14% and 3.91%, respectively. This polarization dependence […]