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We report the transport properties of mechanically exfoliated few-layer SnSe 2 flakes, whose mobility is found with four probe measurements to be ~ 85 cm 2 V -1 s -1 at 300 K, higher than those of the majority of few-layer transitional metal dichalcogenides (TMDs). The mobility increases strongly with decreased temperature, indicating a phonon limited transport. The conductivity of the semiconducting SnSe 2 shows a metallic behavior, which is explained by two competing factors involving the different temperature dependence of mobility and carrier density. The Fermi level is found to be 87 meV below the conduction band minima (CBM) at 300 K and 12 meV below the CBM at 78 K, resulting from a heavy n-type doping. Previous studies have found SnSe 2 field-effect transistors (FETs) to be very difficult to turn off. We find the limiting factor to be the flake thickness compared with the maximum depletion width. With fully depleted devices, we are able to achieve a current on-off ratio of ~10 5 . These results demonstrate the great potential of SnSe 2 as a two dimensional (2D) semiconducting material and are helpful for our understanding of other heavily doped 2D materials. a)

A small amount of carbon nanotubes (CNTs) was added into poly(vinylidene fluoride) (PVDF)/boron nitride (BN) composites through melt blending processing. The thermal conductivity, microstructure changes including the crystallization behavior of PVDF matrix and the dispersion states of fillers in the composites, and the electrical conductivity of the composites were comparatively investigated. The results demonstrated that compared with the PVDF/BN composites at the same BN content, the ternary PVDF/BN/CNT composites exhibited largely enhanced thermal conductivity. In the PVDF/BN/CNT composites, the crystallinity of the PVDF matrix was slightly increased while the crystal form remained invariant. BN particles exhibited homogeneous dispersion in the PVDF/BN composites, and they did not affect the rheological properties of the PVDF/BN composites when the BN content was lower than 10 wt %. The presence of CNTs did not affect the interfacial adhesion between BN and PVDF, but they facilitated the formation of denser BN/CNT network structure in the composites. The mechanisms were then proposed to explain the largely enhanced thermal conductivity of the PVDF/BN/CNT composites. Furthermore, the dielectric property measurements demonstrated that the PVDF/BN/CNT composites containing relatively low BN content exhibited a high dielectric constant with a low dielectric loss. This endowed the PVDF/BN/CNT composites with a greater potential application in the field of electronic devices.

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Artificial photosynthetic systems store solar energy in chemical fuels via CO2 reduction or renewable hydrogen from water splitting. But only relatively moderate CO2-reducing solar-to-fuel efficiency (ηSTF

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In this work, a graphene oxide (GO)-filled polypropylene (PP) adsorptive membrane was developed through an environmentally benign plasma-treatment technology. The PP/GO composite membrane was prepared through melt-compounding and subsequent compression molding processing.The composite membrane was further modified through the plasma treatment with allylamine as the monomer. The results showed that the modified composite membrane exhibited a high hydrophilicity, which is attributed to the introduction of a large number of nitrogen-containing and oxygen-containing groups. The plasma assisted surface modification technology was applied to the porous composite membrane that was prepared through uniaxial stretching processing. Although the porosity of the porous membrane gradually decreased with increasing discharge time during the plasma treatment, the modified porous membrane exhibited an excellent adsorption ability. When adsorbing the particles from the solution, the amount of adsorbed Congo-red particles increased with increasing discharge time. The adsorption mechanism of the treated porous membrane was then analyzed. This work provides an efficient method to apparently improve the hydrophilicity and adsorption ability of PP-based composite membrane which has great potential in the field of wastewater treatment.Through a plasma treatment, a PP-based composite membrane with a high hydrophilicity and an excellent adsorption ability was developed.