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Recharge in seconds and efficiently store power for weeks between charges. Added bonus is the cheap and abundant components needed. One of the applications they foresee is to attach such a super-capacitor to the back of solar panels to store the power and discharge this during the night

very nice indeed - is this already at a stage where we should have a closer look at it? what you think? With experience in growing carbon nanostructures, Pint's group decided to try to coat the porous silicon surface with carbon. "We had no idea what would happen," said Pint. "Typically, researchers grow graphene from silicon-carbide materials at temperatures in excess of 1400 degrees Celsius. But at lower temperatures - 600 to 700 degrees Celsius - we certainly didn't expect graphene-like material growth." When the researchers pulled the porous silicon out of the furnace, they found that it had turned from orange to purple or black. When they inspected it under a powerful scanning electron microscope they found that it looked nearly identical to the original material but it was coated by a layer of graphene a few nanometers thick. When the researchers tested the coated material they found that it had chemically stabilized the silicon surface. When they used it to make supercapacitors, they found that the graphene coating improved energy densities by over two orders of magnitude compared to those made from uncoated porous silicon and significantly better than commercial supercapacitors. Transmission electron microscope image of the surface of porous silicon coated with graphene. The coating consists of a thin layer of 5-10 layers of graphene which filled pores with diameters less than 2-3 nanometers and so did not alter the nanoscale architecture of the underlying silicon. (Cary Pint / Vanderbilt) The graphene layer acts as an atomically thin protective coating. Pint and his group argue that this approach isn't limited to graphene. "The ability to engineer surfaces with atomically thin layers of materials combined with the control achieved in designing porous materials opens opportunities for a number of different applications beyond energy storage," he said.

any clue how? "With the peel-and-stick process, we integrated hydrogenated amorphous silicon (a-Si:H) TFSCs on paper, plastics, cell phone and building windows while maintaining the original 7.5% efficiency. The new peel-and-stick process enables further reduction of the cost and weight for TFSCs and endows TFSCs with flexibility and attachability for broader application areas. We believe that the peel-and-stick process can be applied to thin film electronics as well"

The loss rate of Mars' original atmosphere apparently has been quantified through isotope ratio measurements. Should be useful for climate engineering studies (Isabelle & Markus ?)

A UK-based start-up is developing printable, thin-film plastic solar cells aimed at providing affordable electricity to individual dwellings that have no grid connection, such as those in rural Africa

Thin-film solar cells could be made far more efficient with the addition of bundles of carbon nanotubes.

Lionel could you have a closer look at this one?

A startup with a secret recipe for printing cheap solar cells on aluminum foil debuted today, in what could end up a milestone.

fantastic!!!

thin flexible sheets that can transmit electrical energy to nearby devices without the need for direct electrical contact.

May be interesting for the Tallha proposal of grabbing solar cells with thin wires to avoid the common illumination reduction by the contacts.

Is this for real ?

Very interesting, indeed! I wonder if it even can be beefed up. The devices produce a sustained voltage of around 0.5 volts across a 7-micrometre-thick film, with a current density of around 17 microamperes per square centimetre

You were a bit faster than me! On top is the corresponding paper.

I think there are a few difficulties when assuming that the macroscopic block of glass will accelerate instantaneously. Also, if I prevent the block from moving would it become perfectly reflective as no momentum can be transferred to it? One could say that the momentum is then transferred to the larger system that holds the glass. But surely I could make that system (or even the block of glass) so heavy that it would not move more than Planck's length during the passage of the photon - especially if the glass is very thin or the light is very red.

Bacterial wires explain enigmatic electric currents in the seabed: Each one of these 'cable bacteria' contains a bundle of insulated wires that conduct an electric current from one end to the other. Cable bacteria explain electric currents in the seabed Electricity and seawater are usually a bad mix.

WOW!!!! don't want to even imagine what we do to these with the trailing fishing boats that sweep through sea beds with large masses .... "Our experiments showed that the electric connections in the seabed must be solid structures built by bacteria," says PhD student Christian Pfeffer, Aarhus University. He could interrupt the electric currents by pulling a thin wire horizontally through the seafloor. Just as when an excavator cuts our electric cables. In microscopes, scientists found a hitherto unknown type of long, multi-cellular bacteria that was always present when scientists measured the electric currents. "The incredible idea that these bacteria should be electric cables really fell into place when, inside the bacteria, we saw wire-like strings enclosed by a membrane," says Nils Risgaard-Petersen, Aarhus University. Kilometers of living cables The bacterium is one hundred times thinner than a hair and the whole bacterium functions as an electric cable with a number of insulated wires within it. Quite similar to the electric cables we know from our daily lives. "Such unique insulated biological wires seem simple but with incredible complexity at nanoscale," says PhD student Jie Song, Aarhus University, who used nanotools to map the electrical properties of the cable bacteria. In an undisturbed seabed more than tens of thousands kilometers cable bacteria live under a single square meter seabed. The ability to conduct an electric current gives cable bacteria such large benefits that it conquers much of the energy from decomposition processes in the seabed. Unlike all other known forms of life, cable bacteria maintain an efficient combustion down in the oxygen-free part of the seabed. It only requires that one end of the individual reaches the oxygen which the seawater provides to the top millimeters of the seabed. The combustion is a transfer of the electrons of the food to oxygen which the bacterial inner wires manage over centimeter-long distances. However, s

The Opportunity rover, which landed on Mars nearly eight years ago, has discovered a thin, bright mineral vein along the rim of a huge crater called Endeavour. This mineral is almost certainly gypsum that was deposited by liquid water billions of years ago, researchers said.

Physicists in the US have made the first ultrathin flat lens. Thanks to its flatness, the device eliminates optical aberrations that occur in conventional lenses with spherical surfaces. As a result, the focusing power of the lens also approaches the ultimate physical limit set by the laws of diffraction.

Really nice indeed! The new flat ultrathin lens is different in that it is a nanostructured "metasurface" made of optically thin beam-shaping elements called optical antennas, which are separated by distances shorter than the wavelength of the light they are designed to focus. These antennas are wavelength-scale metallic elements that introduce a slight phase delay in a light ray that scatters off them. The metasurface can be tuned for specific wavelengths of light by simply changing the size, angle and spacing between the nanoantennas. "The antenna is nothing more than a resonator that stores light and then releases it after a short time delay," Capasso says. "This delay changes the direction of the light in the same way that a thick glass lens would." The lens surface is patterned with antennas of different shapes and sizes that are oriented in different directions. This causes the phase delays to be radially distributed around the lens so that light rays are increasingly refracted further away from the centre, something that has the effect of focusing the incident light to a precise point.

Plastic needs a timescale of millenia to dissolve in the ocean and in the meantime it is accumulated in the water due to systematic dumping of garbage in the ocean since decades. Deploying buoyant devices at the location of the gyres (permanent circular currents in the ocean) is proposed for collecting the thin particles. The ambitious concept was developped by a Delft student, presented at a TEDx (see link), made a feasibility study through crowdfunding and now announces a public contest for developing mechanical parts of the harvesting system.

Using dielectric materials as efficient EM radiators and receivers can scale down these antenna's to the chip level, reducing both weight and power consumption. The infamous internet-of-things one step closer. But could we also transmit power this way?? "In dielectric aerials, the medium has high permittivity, meaning that the velocity of the radio wave decreases as it enters the medium," said Dr Dhiraj Sinha, the paper's lead author. "What hasn't been known is how the dielectric medium results in emission of electromagnetic waves. This mystery has puzzled scientists and engineers for more than 60 years." The researchers determined that the reason for this phenomenon is due to symmetry breaking of the electric field associated with the electron acceleration The researchers found that by subjecting the piezoelectric thin films to an asymmetric excitation, the symmetry of the system is similarly broken, resulting in a corresponding symmetry breaking of the electric field, and the generation of electromagnetic radiation.

A good example of "Can we use it for space.com"... For shielding of course !