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    Category Physics

    New Advance toward more Practical, Low-cost, “Greener” Solar Cells with halide perovskite

    September 29, 2016, Categories  Physics, Technology/Electronics, Chemistry/Nanotechnology

    Mixed tin (Sn)–lead (Pb) perovskites with high Sn content exhibit low bandgaps suitable for fabricating the bottom cell of perovskite-based tandem solar cells. In this work, we report on the fabrication of efficient mixed Sn–Pb perovskite solar cells using precursors combining formamidinium tin iodide (FASnI3) and methylammonium lead iodide (MAPbI3). The best-performing cell fabricated using a (FASnI3)0.6(MAPbI3)0.4 absorber with an absorption edge of ∼1.2 eV achieved a power conversion efficiency (PCE) of 15.08 (15.00)% with an open-circuit voltage of 0.795 (0.799) V, a short-circuit current density of 26.86(26.82) mA/cm2, and a fill factor of 70.6(70.0)% when measured under forward (reverse) voltage scan. The average PCE of 50 cells we have fabricated is 14.39 ± 0.33%, indicating good reproducibility.

    Mixed tin (Sn)–lead (Pb) perovskites with high Sn content exhibit low bandgaps suitable for fabricating the bottom cell of perovskite-based tandem solar cells. In this work, we report on the fabrication of efficient mixed Sn–Pb perovskite solar cells using precursors combining formamidinium tin iodide (FASnI3) and methylammonium lead iodide (MAPbI3). The best-performing cell fabricated using a (FASnI3)0.6(MAPbI3)0.4 absorber with an absorption edge of ∼1.2 eV achieved a power conversion efficiency (PCE) of 15.08 (15.00)% with an open-circuit voltage of 0.795 (0.799) V, a short-circuit current density of 26.86(26.82) mA/cm2, and a fill factor of 70.6(70.0)% when measured under forward (reverse) voltage scan. The average PCE of 50 cells we have fabricated is 14.39 ± 0...

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    ‘Missing link’ found in development of Bioelectronic Medicines

    September 28, 2016, Categories  Technology/Electronics, Physics

    Memristor chip. Credit: Image courtesy of University of Southampton

    Memristor chip. Credit: Image courtesy of University of Southampton

    A nanoscale device, called a memristor, could be the ‘missing link’ in the development of implants that use electrical signals from the brain to help treat medical conditions. Monitoring neuronal cell activity is fundamental to neuroscience and the development of neuroprosthetics – biomedically engineered devices that are driven by neural activity. However, a persistent problem is the device being able to process the neural data in real-time, which imposes restrictive requirements on bandwidth, energy and computation capacity.

    In a new study, published in Nature Communications, the researchers showed that memristors could provide real-time processing of neuronal signals (spiking events) leading to efficient data compressio...

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    First Quantum Photonic Circuit with an Electrically Driven Light Source

    September 28, 2016, Categories  Physics, Technology/Electronics

    Carbon tube (center) as a photon source and superconducting nanowires as receivers constitute part of the optical chip. Credit: W.Pernice/WWU

    Carbon tube (center) as a photon source and superconducting nanowires as receivers constitute part of the optical chip. Credit: W.Pernice/WWU

    Whether for use in safe data encryption, ultrafast calculation of huge data volumes or so-called quantum simulation of highly complex systems: Optical quantum computers are a source of hope for tomorrow’s computer technology. For the first time, scientists now have succeeded in placing a complete quantum optical structure on a chip. This fulfills one condition for the use of photonic circuits in optical quantum computers.

    The light source for the quantum photonic circuit used by the scientists for the first time were special nanotubes made of carbon...

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    Scientists Visualize Quantum Behavior of Hot Electrons for first time

    September 28, 2016, Categories  Physics, Technology/Electronics

    The Scanning Tunnelling Microscope used to inject electrons into a silicon surface at the University of Birmingham. Credit: Michelle Tennison

    The Scanning Tunnelling Microscope used to inject electrons into a silicon surface at the University of Birmingham. Credit: Michelle Tennison

    The findings present a promising step forward towards being able to manipulate and control the behavior of high energy, or ‘hot’, electrons. A Scanning Tunnelling Microscope was used to inject electrons into a silicon surface, decorated with toluene molecules. As the injected charge propagated from the tip, it induced the molecules to react and ‘lift off’ from the surface. By measuring the precise atomic positions from which molecules departed on injection, the team were able to identify that electrons were governed by quantum mechanics close to the tip, and then by more classical behavior further away.

    The team found the molecular lift-off was “su...

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