Nanowerk November 26, 2024 Materials with axis-dependent conduction polarity (ADCP), which exhibit electron-like and hole-like conduction along distinct crystallographic axes, have garnered interest as potential candidates for effective transverse thermoelectric (TTE) conversion. However, the challenge of designing materials with ADCP is still unresolved. Researchers in Japan conducted experimental and computational investigations on the ADCP in thermopower of WSi single crystals and found that the ADCP stems from the mixed-dimensionality of the Fermi surfaces, characterized by the coexistence of quasi-one-dimensional electron-like and quasi-two-dimensional hole-like sheets. They demonstrated TTE conversion in WSi single crystals by detecting the electromotive force along the perpendicular […]
Category Archives: Energy
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 […]
Quantum-inspired design boosts efficiency of heat-to-electricity conversion
Phys.org November 21, 2024 Thermophotovoltaics (TPV) is promising for thermal storage and generation. TPV systems employing selective thermal emitters allow compact designs for various terrestrial and space applications, but these systems have low efficiency. The selective thermal emitter and the low-bandgap photovoltaic cell contribute to this problem. Researchers at Rice University solved the shortcomings of the thermal emitter by using a novel approach based on non-Hermitian optics. They demonstrated a hybrid metal-dielectric non-Hermitian selective emitter (NHE) with high spectral efficiency and employed the NHE in a TPV system operating at 1273 K. They showed that a maximum TPV conversion efficiency of […]
China Will Have 1 Trillion Watts of Solar by the end of 2025
Next Big Future July 3, 2024 The National Energy Administration (NEA) reports China added 217GW of solar power and 76GW of wind power in 2023 – to reach a total capacity of 1,050GW. They need 15 Tesla Megapack factories (150,000 per year) worth of fixed storage every year for the additional wind and solar. This will increase as China accelerates solar and wind installation to meet AI data center demand. By May 2024, China had installed 690GW of solar capacity and 460GW of wind, which made up 38% of its power generation capacity. China is averaging about 1 MWh/year (2.8kWh/day) […]
MXenes for energy storage: Chemical imaging more than just surface deep
Phys.org June 17, 2024 Due to their versatile tunable properties MXene flakes are used as electrodes in lithium-ion batteries and diverse applications, from energy storage to electromagnetic shielding. However, the local distribution of surface functional groups over single flakes and within few- or multilayered flakes remains unclear. An international team of researchers (Germany, France) introduced scanning X-ray microscopy (SXM) with simultaneous transmission and electron yield detection of individual MXene flakes enabling multimodal nanoscale chemical imaging with bulk and surface sensitivity, respectively. The Ti chemical bonding environment is found to significantly vary between few-layered and multilayered MXenes. Simultaneous bulk and surface […]
A flexible and efficient DC power converter for sustainable-energy microgrids
Science Daily April 19, 2024 An internal team of researchers (Japan, Taiwan) proposed a floating four-phase interleaved chargepump bidirectional dc-dc converter (F4P-ICPBDC) with wide Buck/Boost voltage ratio. The interleaved structure was used to mitigate the current ripple across the low-voltage side capacitor and inductors, while the floating configuration facilitated the high Buck/Boost voltage conversion ratio. To ensure a balanced average inductor current throughout the entire range of duty cycle, an asymmetric duty limit control strategy was implemented. Bidirectional synchronous rectification operations were seamlessly carried out without the need for additional hardware, which enhanced the overall converter efficiency. They developed a […]
Discovery of organic catalyst could lead to cheaper fuel cells
Phys.org April 15, 2024 Researchers at the University of Virginia have developed an iminium-based organoelectrocatalyst (im+) for oxygen reduction reaction with trifluoroacetic acid as a proton source in acetonitrile solution under both electrochemical and spectrochemical conditions using decamethylferrocene as a chemical reductant. Under spectrochemical conditions, H2O2 was the primary reaction product. They attributed this difference in selectivity to the interception of the free superoxide intermediate under electrochemical conditions by the reduced catalyst… read more. Open Access TECHNICAL ARTICLE
Magnetic fields boost clean energy
Nanowerk April 7, 2024 Magnetic field effects on electrocatalysis have recently gained attention due to the substantial enhancement of the oxygen evolution reaction (OER) on ferromagnetic catalysts. An international team of researchers (Switzerland, Argentina) used a specifically designed magneto-electrochemical system and non-magnetic electrodes to quantify magnetic field effects. They found marginal enhancement in reactions with high reactant availability, such as the OER, whereas substantial boosts exceeding 50% were observed in diffusion limited reactions, exemplified by the oxygen reduction reaction (ORR). According to the researchers their results advanced the fundamental understanding of magnetic fields in electrocatalysis and unveil new prospects for […]
New device gathers, stores electricity in remote settings
Science Daily April 9, 2024 Researchers at the University of Utah investigated a pyro electrochemical cell (PEC) as a novel device concept for direct conversion of thermal energy to stored electrochemical energy. The PEC integrated a porous, pyroelectric separator within a supercapacitor. The pyroelectric separator induced an electric field within the PEC when exposed to a temperature change with time. The electric field drove ions into electrode double layers to charge the cell. Experimental results were coupled with simulations to explore PEC response when thermally cycled, with predicted pyroelectric orientation effects observed in two tests. The pyroelectric separator showed a […]