Nanowerk June 15, 2021 Previously researchers succeeded in demonstrating the phenomenon of perfect absorption in large bodies of matter that were several times the size of a light beam. But the question remained unsolved was – whether the same was possible for miniature objects. An international team of researchers (Russia, Sweden) calculated the properties of a small object that could completely absorb all incidental light. They succeeded in reducing this complex analytical task to a simpler one – a Fredholm integral equation of the second kind. Having solved it, they found the ideal combination of particle and light properties that […]
Category Archives: Energy
Saving the climate with solar fuel
EurekAlert June 8, 2021 Synthetic methane is easy to substitute in the vehicle fleet as the existing infrastructure – grid, storage, filling stations and trade mechanisms allow a comparatively fast substitution of fossil natural gas by synthetic methane for light and heavy-duty vehicles. Researchers in Switzerland discussed the direct potential for substitution of parts of the newly registered vehicle fleet with gas vehicles, fueled with synthetic methane, and compared it to the potential of using fuel cell electric vehicles relying on hydrogen. They analyzed the production path of hydrogen and synthetic methane with respect to electricity demand and overall associated […]
Scientists unravel noise-assisted signal amplification in systems with memory
Phys.org May 27, 2021 Signals can be amplified by an optimum amount of noise, but stochastic resonance (SR) is a fragile phenomenon. To investigate the role of memory for this phenomenon an international team of researchers (the Netherlands, UK) used an oil-filled microcavity which, driven by a continuous wave laser, has memory in its nonlinear optical response. Modulating the cavity length while adding noise to the driving laser, they observed a peak in the transmitted signal-to-noise ratio as a function of the noise variance. Through simulations, they reproduced their observations and extrapolated that the SR bandwidth could be approximately 3000 […]
A new device can light up 100 LED bulbs with a single drop of water (w/video)
Nanowerk May 10, 2021 The water-droplet/solid-based triboelectric nanogenerator, has so far generated peak power densities of less than one watt per square metre, due to the limitations imposed by interfacial effects. An international team of researchers (China, USA – University of Nebraska, Hong Kong) has developed a droplet-based electricity generator (DEG) using polytetrafluoroethylene (PTFE) film on an indium tin oxide substrate plus an aluminium electrode. When the spreading water connects the two electrodes, all the stored charges on the PTFE can be fully released to generate an electric current. As a result, both the instantaneous power density and energy conversion […]
Carbon-neutral ‘biofuel’ from lakes
Science Daily March 31, 2021 Although the greenhouse gas methane is less well known and much rarer in the atmosphere, its global warming potential is 80 to 100 times greater per unit. Methane from lakes and water reservoirs makes up about 20% of global natural methane missions. Researchers in Switzerland outline the potential and theoretical possibilities for using methane from lakes and other freshwater bodies for sustainable energy production. The feasibility of up-scaled adsorption-driven technologies to capture and refine aqueous Biogenic CH4 is mostly generated from biomass produced through atmospheric CO2 uptake. Its exploitation in freshwaters can thus secure large […]
No losses: Scientists stuff graphene with light
EurekAlert November 16, 2020 Researchers in Russia developed a technique to achieve 90% energy conversion from the pump laser field to the surface plasmon polaritons (SPPs) on the base of the hybrid optoplasmonic multi‐level scheme of near‐resonant interaction with semiconductor quantum dots (QDs) placed in the proximity of a graphene surface. Using numerical simulations and semiclassical approach for the light–matter interaction they found that maximum efficiency of SPP generation is achieved in strong coupling conditions for a stationary regime of SPP‐QD interaction. The technique can be used for converting energy in solar cells, and nano and bio-object detection…read more. TECHNICAL […]
Building walls that will make summer heat waves more bearable
Phys.org September 28, 2020 A team of researchers in South Korea propose Phase Change Material (PCM) wall device using bubble injection method for the application of PCM in building envelopes. The density difference between PCM and bubbles causes the upward movement of the bubbles and flow in the liquid PCM destroying temperature stratification in the PCM and heat penetration across the PCM is reduced. With the application of the bubble injection method, 11% more latent heat energy was stored in the PCM, 28% less heat penetrated across the PCM wall and the average flow rate inside the liquid PCM with […]
Faster, more efficient energy storage could stem from holistic study of layered materials
Science Daily August 25, 2020 An international team of researchers (USA – Oak Ridge National Laboratory, Georgia State University, Tulane University, Drexel University, Portugal) integrated theoretical data from computational modeling of experimental data to pinpoint potential locations of a variety of charged ions in titanium carbide, the most studied MXene phase. MXenes are a class of two-dimensional materials constructed in layers that are only a few atoms thick. They were able to form links between theory and different types of materials characterization, ranging from very simple to very complex over a wide range of length and time scales. The study’s […]
Efficient Off-Grid Power, After the Sun Sets
Optics and Photonics August 19, 2020 An international team of researchers (USA – Stanford, Israel) analyzed the basic thermodynamics of a heat engine, with the hot side under the roof and the top of the roof radiating thermal energy out into the environment. They developed models to maximize the amount of electrical power generated for various temperature gradients. The team’s design for a nighttime power generator would occupy a rooftop area of 1 m2. It incorporates a radiative emitting panel, a state-of-the-art TEG made of metal alloy, and a heat sink, with radiation shields and insulative pegs to reduce radiative […]
Engineers develop new fuel cells with twice the operating voltage as hydrogen
EurekAlert June 17, 2020 Researchers at Washington University have developed high-power direct borohydride fuel cells that operate at double the voltage of conventional hydrogen fuel cells. They pioneered a reactant identifying an optimal range of flow rates, flow field architectures and residence times that enable high power operation ensuring proper fuel and oxidant distribution and the mitigation of parasitic reactions. They demonstrated a single-cell operating voltage of 1.4 or greater, double that obtained in conventional hydrogen fuel cells, with peak powers approaching 1 watt/cm2. Doubling the voltage would allow for a smaller, lighter, more efficient fuel cell design. Their approach […]