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We report the novel photoresponse of nanodevices made from azafullerene (C59N)-encapsulated single-walled carbon nanotubes (C59N@SWNTs), so called peapods. The photoconducting properties of a C59N@SWNT are measured over a temperature range of 10 to 300 K under a field-effect transistor configuration. It is found that the photosensitivity of C59N@SWNTs depends very sensitively on the temperature, making them an attractive candidate as a component of nanothermometers covering a wide temperature range. Our results indicate that it is possible to read the temperature by monitoring the optoelectronics signal of C59N@SWNTs. In particular, sensing low temperatures would become more convenient and easy by giving a simple light pulse [ABSTRACT FROM AUTHOR]

Herein, we developed a near-invisible solar cell through a precise control of the contact barrier between an indium tin oxide (ITO) electrode and a monolayer tungsten disulfide (WS2), grown by chemical vapor deposition (CVD). The contact barrier between WS2 and ITO was controlled by coating various thin metals on top of ITO (Mx/ITO) and inserting a thin layer of WO3 between Mx/ITO and the monolayer WS2, which resulted in a drastic increase in the Schottky barrier height (up to 220 meV); this could increase the efficiency of the charge carrier separation in our Schottky-type solar cell. The power conversion efficiency (PCE) of the solar cell with the optimized electrode (WO3/Mx/ITO) was more than 1000 times that of a device using a normal ITO electrode. Large-scale fabrication of the solar cell was also investigated, which revealed that a simple size expansion with large WS2 crystals and parallel long electrodes could not improve the total power (PT) obtained from the complete device even with an increase in the device area; this can be explained by the percolation theory. This problem was addressed by reducing the aspect ratio (width/channel length) of the unit device structure to a value lower than a critical threshold. By repeating the experiments on this optimized unit device with an appropriate number of series and parallel connections, PT could be increased up to 420 pW from a 1-cm2 solar cell with a very high value (79%) of average visible transmission (AVT). [ABSTRACT FROM AUTHOR]

Increase of the water flow rate into atmospheric pressure air discharge plasma for humidification can significantly improve suppressing conidium germination of a plant pathogenic fungus in the liquid phase by its effluent gas exposure. The role of the introduced water includes enhancement of hydrogen supply to the plasma and cooling of the plasma effluent gas. The hydrogen‐containing precursors for antibacterial species generation are experimentally increased. The gas cooling by the latent heat assists dinitrogen pentoxide density in the gas phase, a suggested precursor for antibacterial species generation near the liquid surface. This suggested near‐surface reaction is a second‐order reaction, generally requiring lower precursors concentrations and leading to less residues, thus it can be an important process for agricultural applications. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) attract intence attention due to its unique optoelectrical features. Recent progress in production stage of TMD enables us to synthesis uniform and large area TMD with mono layer thickness. Elucidation of growth mechanism is a challenge to improve the crystallinity of TMD, which is regargeded as a next crutial subject in the production stage. Here we report novel diffusion and nucleation dynamics during tungsten disulphide (WS2) growth. The diffusion length (Ld) of the precursors have been measured with unique nucleation control methods. It was revealed that the Ld reaches up to ~750 μm. This ultra-long diffusion can be attributed to precursor droplets observed during in-situ monitoring of WS2 growth. The integrated synthesis of >35,000 single crystals and monolayer WS2 was achieved at the wafer scale based on this model. Our findings are highly significant for both the fundamental study of droplet-mediated crystal growth and the industrial application of integrated single-crystal TMDs. [ABSTRACT FROM AUTHOR]

We have developed a new liquid‐phase noncatalytic selective oxidation of polyhydric alcohols such as glycerol. This method involves the use of a nonthermal atmospheric‐pressure plasma instead of precious‐metal catalysts. We found that noncatalytic selective oxidation of glycerol achieved a conversion comparable to that achieved by gold‐catalyzed oxidation, and the desired glyceric acid, which is a pharmaceutical raw material, was obtained. When the solution pH was changed from strongly alkaline to neutral, the main reaction switched from the one that occurs in the presence of gold catalysts to the one that occurs in the presence of platinum catalysts. These results suggest that the reactive oxygen species generated by nonthermal atmospheric‐pressure plasma irradiation vary depending on the solution pH. [ABSTRACT FROM AUTHOR]

Graphene nanoribbon (GNR), also known as 1-dimensional graphene, with a non-zero band gap has a huge potential for various electrical and optoelectrical applications because of its high transparency, flexibility, controllable band gap, and unique edge states. Recent advances in the synthesis of GNR enable us to show the possibility of GNRs as future high performance electrical devices. However, the applicability of GNRs to optoelectrical devices is unclear. Here we report that suspended GNR devices can show persistent photoconductivity (PPC) with long decay time (over 72 h) and adequate environmental stability. Repeated non-volatile memory operation is also demonstrated with an integrated PPC device using GNRs. This very stable PPC device can be applied to a wide variety of fields such as ultra-low-power non-volatile memory, nanoscale imaging, and biological sensors. Our results have opened the door to advance the study of GNRs in novel directions such as optoelectrical applications. [ABSTRACT FROM AUTHOR]

The control authority of a nanosecond-pulse-driven dielectric-barrier discharge plasma actuator (ns-DBDPA) was evaluated via wind tunnel experiments with the simultaneous measurement of lift and drag forces, pressure on the airfoil surface, and particle image velocimetry (PIV) measurements. In these experiments, a Reynolds number of Re = 2.6 × 105 was applied with a freestream velocity of 40 m/s under atmospheric pressure. The force measurements revealed multiple peaks of lift force recovery and drag force modulation depending on the angle of attack, α, and non-dimensional frequency, F+. At the positive post-stall α close to stall α of approximately 16°, F+ values around 2.0 were effective for lift recovery and drag reduction. When the deep-stall angle α is larger than 20° (either positive or negative), relatively low F+ values around 0.25 were effective for lift recovery. When actuating at a deep-stall angle corresponding to F+ = 0.25, the surface pressure measurements showed that a near flat pressure distribution is formed on the suction side, and the PIV measurement showed that this near flat distribution is caused by the increase in backflow velocity near the surface of the airfoil. This backflow enhancement near the suction side surface leads to the reduction in pressure in separated flow, resulting in significant increases in the lift and drag coefficients. Thus, this simultaneous measurement of force, pressure, and PIV is capable of evaluating the multiple control modes underlying lift and drag control by ns-DBDPA.Graphical abstract: [ABSTRACT FROM AUTHOR]

The article presents a study which investigated the photoinduced electrical transport properties of azafullerene encapsulated single-walled carbon nanotubes (C59N@SWNTs). The study demonstrated that azafullerene molecules inside SWNTs make nanotubes sensitive to light, and that the conductance of C59N@SWNTs changes abruptly upon light illumination, which suggests that photoinduced charge transfer in responsible for changes of conductivity.