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Experimental evidence of the optimized interface engineering effects in MoS₂ transistors is demonstrated. The MoS₂/Y₂O₃/HfO₂ stack offers excellent interface control. Results show that HfO₂ layer can be scaled down to 9 nm, yet achieving a near-ideal sub-threshold slope (65 mv/dec) and the highest saturation current (526 μA/μm) of any MoS₂ transistor reported to date.

Surface-modified ZnS nanoparticles have been fabricated, and the morphologies and crystalline structures of the powder have been characterised by transmission electron microscopy, X-ray diffraction and Fourier transformation infrared spectrum. The tribological properties of the surface-modified ZnS (SM-ZnS) nanoparticles as an additive in PEG400 were evaluated with a four-ball tester. It was found that the as-prepared SM-ZnS nanoparticles had a very narrow size distribution, with the average diameter about 5–10 nm. The SM-ZnS nanoparticles as the additive led to an obvious improvement in the anti-wear and friction-reduction properties of the synthetic PEG400. Analysis indicated that a boundary film was formed during the friction process. Copyright © 2014 John Wiley & Sons, Ltd.

Lattice-strained CdTe/CdS:Cu quantum dots (QDs) with a widely tunable near-infrared (NIR) fluorescence emission spectrum (700–910 nm) and long lifetime (up to 1 μs) are synthesized. Based on the multiemission and multi-lifetime of the well-defined QDs, NIR-emitting two-dimensional (2D) codes are achieved by embedding as-prepared QDs into agarose beads. This provides a new strategy for fluorescent 2D codes.

Precise tuning of the 2D carrier density by using fractional δ-doping of d electrons improves the thermoelectric properties of oxide heterostructures. This promising result can be attributed to the anisotropic band structure in the 2D system, indicating that δ-doped oxide superlattices are good candidates for advanced thermoelectrics.

A novel two-terminal high-speed nonvolatile memory device is demonstrated featuring the construction of a quasi-metal-insulator-semiconductor (q-MIS) architecture. The quasi-MIS memory takes advantage of an in situ formed amorphous AlO_x interfacial layer sandwiched between p-type ZnS nanoribbons (p-ZnSNRs) and a Al electrode. Systematical optimization of the AlO_x interfacial layer enables the resultant memory to show excellent memory characteristics, including a fast programming speed of <100 ns, a high current ON/OFF ratio of ∼10⁸, a long retention time of 6 × 10⁴ s, and good stability over 12 months. In addition, an interface-state-induced mechanism is proposed to elucidate in detail the memory characteristic for the quasi-MIS structure. This work suggests great potential of such quasi-MIS architecture for high-performance two-terminal memory, and more importantly, signifies the importance of interface engineering for the construction of novel functional nano-devices.

Charge trapping/detrapping in the ultrathin alumina interfacial layer leads to the high-speed nonvolatile memory effect of the quasi-metal-insulator-semiconductor memory.

Although the high impermeability of graphene makes it an excellent barrier to inhibit metal oxidation and corrosion, graphene can form a galvanic cell with the underlying metal that promotes corrosion of the metal in the long term. Boron nitride (BN) nanosheets which have a similar impermeability could be a better choice as protective barrier, because they are more thermally and chemically stable than graphene and, more importantly, do not cause galvanic corrosion due to their electrical insulation. In this study, the performance of commercially available BN nanosheets grown by chemical vapor deposition as a protective coating on metal has been investigated. The heating of the copper foil covered with the BN nanosheet at 250 °C in air over 100 h results in dramatically less oxidation than the bare copper foil heated for 2 h under the same conditions. The electrochemical analyses reveal that the BN nanosheet coating can increase open circuit potential and possibly reduce oxidation of the underlying copper foil in sodium chloride solution. These results indicate that BN nanosheets are a good candidate for oxidation and corrosion protection, although conductive atomic force microscopy analyses show that the effectiveness of the protection relies on the quality of BN nanosheets.

Boron nitride nanosheets have desirable properties of metal protection against oxidation and corrosion, without causing galvanic corrosion as in the case of graphene

Lubricant oil can be regarded as a complex mixture of base oils and additives, each one with its specific functions and behaviour. In this paper, the interaction of a molybdenum dialkyldithiocarbamate (MoDTC)-based additive and combinations of a polyalphaolefin and a synthetic ester is investigated. A reciprocating ball-on-disc configuration was used for tribological tests. The effect of MoDTC is seen as a sharp drop in the coefficient of friction. This friction reduction is affected by the base fluid: the effect is more intense and lasts longer when the ester content is decreased. The applied normal force also affects the MoDTC effect, which is not sustainable at higher loads. Copyright © 2014 John Wiley & Sons, Ltd.

Reversible photo-induced performance deterioration is observed in mesoporous TiO₂-containing devices in an inert environment. This phenomenon is correlated with the activation of deep trap sites due to astoichiometry of the metal oxide. Interestingly, in air, these defects can be passivated by oxygen adsorption. These results show that the doping of TiO₂ with aluminium has a striking impact upon the density of sub-gap states and enhances the conductivity by orders of magnitude. Dye-sensitized and perovskite solar cells employing Al-doped TiO₂ have increased device efficiencies and significantly enhanced operational device stability in inert atmospheres. This performance and stability enhancement is attributed to the substitutional incorporation of Al in the anatase lattice, “permanently” passivating electronic trap sites in the bulk and at the surface of the TiO₂.

Reversible, photo-induced performance deterioration in TiO₂-containing devices is reported in an inert environment. This phenomenon is correlated with the activation of deep trap sites in the metal oxide due to astoichiometry. Substitutional incorporation of Al in the anatase lattice, “permanently” passivating electronic trap sites in the bulk and at the surface of the TiO₂, results in improved device efficiencies and operational device stability in inert atmospheres.

The possibility to induce magnetism in light-element materials that contain only s and p electrons is of fundamental and practical importance. Here, weak high-temperature ferromagnetism is observed in carbon-doped boron nitride (B-C-N) nanosheets. The bulk-quantities of B-C-N nanosheets that are free of metallic impurities are prepared through a multi-step process. These B-C-N samples exhibit ferromagnetic hysteresis stable at room temperature and above, with saturation magnetization and coercivity comparable to the previously reported results of defective graphite samples. The ferromagnetic response disappears upon the removal of carbon dopants from the BN lattice, indicating that the observed magnetism originates from substitutional carbon-doping rather than from extrinsic magnetic impurities. On the basis of first-principle calculations it is shown that not only substitutional carbon doping in a honeycomb BN lattice favors spontaneous spin polarization and local moment formation, but also that the spin moments can exhibit long-range magnetic ordering.

Room temperature ferromagnetism is demonstrated in carbon-doped boron nitride (BN) nanosheets with a substantial degree of doping. Notably, the ferromagnetic response disappears upon the controlled removal of carbon dopants from the BN lattice, indicating that the observed magnetism originates from effects of substitutional carbon-doping rather than from extrinsic magnetic impurities.

MoS₂, TaS₂, TiS₂, WSe₂ and TaSe₂ nanobelts decorated with a PtAg alloy or Pt NPs have been successfully synthesized by etching 2D nanosheets under a mild reaction condition followed by a subsequent nanosheet-to-nanobelt transformation mediated by the PVP template. The PtAg-MoS₂ hybrid nanobelt coated with PVP is used as the active material in a memory device, which exhibits hysteresis behavior with the function of dynamic random access memory.

Multifunctional pillared materials are synthesized by the intercalation of cage-shaped adamantylamine (ADMA) molecules into the interlayer space of graphite oxide (GO) and aluminosilicate clays. The physicochemical and structural properties of these hybrids, determined by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Raman and X-ray photoemission (XPS) spectroscopies and transmission electron microscopy (TEM) show that they can serve as tunable hydrophobic/hydrophilic and stereospecific nanotemplates. Thus, in ADMA-pillared clay hybrids, the phyllomorphous clay provides a hydrophilic nanoenvironment where the local hydrophobicity is modulated by the presence of ADMA moieties. On the other hand, in the ADMA-GO hybrid, both the aromatic rings of GO sheets and the ADMA molecules define a hydrophobic nanoenvironment where sp³-oxo moieties (epoxy, hydroxyl and carboxyl groups), present on GO, modulate hydrophilicity. As test applications, these pillared nanostructures are capable of selective/stereospecific trapping of small chlorophenols or can act as cytotoxic agents.

A new type of multifunctional pillared, layered material synthesized by the intercalation of cage-shaped adamantylamine molecules into the interlayer space of graphite oxide and layered aluminosilicate nanoclays is developed, exhibiting antiproliferative activity for cells, as well as high adsorption ability to small organic pollutants from aqueous solutions.