A high-performance and low-cost pasted nickel electrode made from a metal fiber substrate has been developed. The electrode is designed so that it exhibits active material utilization close to 100%, with an energy density as high as 170 mAh/g or 520 mAh/cm 3. This high active material utilization, even with a metal fiber substrate, which is a poor current collector compared with a conventional sintered nickel powder plaque, has been made possible by adding CoO which dissolves and precipitates on the surface of nickel hydroxide particles as [~-Co(OH)2 during standing and then is converted to CoOOH during the subsequent charging, which provides a good electrical path between the nickel hydroxide particles and the metal fiber substrate. Thus-formed CoOOH is not reduced in the subsequent discharges of the electrode and serves as a good current collector to ensure a high active material utilization throughout the life of the electrode.

Semiconductor heterojunction interfaces have been an important topic, both in modern solid state physics and in electronics and optoelectronics applications. Recently, the heterojunctions of atomically-thin transition metal dichalcogenides (TMDCs) are expected to realize one-dimensional (1D) electronic systems at their heterointerfaces due to their tunable electronic properties. Herein, we report unique conductivity enhancement and electrical potential modulation of heterojunction interfaces based on TMDC bilayers consisted of MoS2 and WS2. Scanning tunneling microscopy/spectroscopy analyses showed the formation of 1D confining potential (potential barrier) in the valence (conduction) band, as well as bandgap narrowing around the heterointerface. The modulation of electronic properties were also probed as the increase of current in conducting atomic force microscopy. Notably, the observed band bending can be explained by the presence of 1D fixed charges around the heterointerface. The present findings indicate that the atomic layer heterojunctions provide a novel approach to realizing tunable 1D electrical potential for embedded quantum wires and ultrashort barriers of electrical transport.

It is demonstrated that high performance and low‐cost pasted nickel electrodes with an active material utilization close to 100% and an energy density of 170 mAh/g can be prepared from a metal fiber substrate pasted with Ni(OH)2 by addition of CoO.

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Conductance fluctuation of edge-disordered graphene nanoribbons (ED-GNRs) is examined using the non-equilibrium Green's function technique combined with the extended Hückel approximation. The mean free path λ and the localization length ξ of the ED-GNRs are determined to classify the quantum transport regimes. In the diffusive regime where the length Lc of the ED-GNRs is much longer than λ and much shorter than ξ, the conductance histogram is given by a Gaussian distribution function with universal conductance fluctuation. In the localization regime where Lc≫ξ, the histogram is no longer the universal Gaussian distribution but a lognormal distribution that characterizes Anderson localization.

Synopsis The relationship between the sharpness of secondary recrystallization texture and the morphology of AlN during secondary recrystallization was investigated through changing the dew point of primary annealing and the dew point and the N2 partial pressure of secondary annealing atmosphere. The main conclusion is summarized in the following. (1) The secondary recrystallization initiates near the surface layer of primary matrix when a gradient of the intensity of the inhibitor along the thickness direction is formed and reaches to a certain level at the specific temperature while the matrix grains are inhibited to grow because of the higher intensity of inhibitor. Here the intensity of inhibitor is defined as f/ r (f: volume fraction of AlN or MnS, r: mean radius of AlN or MnS). The intensity gradient of A1N along the thickness direction is formed by the selective oxidation of Al during secondary recrystallization annealing. (2) A critical temperature (Tcr) is required for the initiation of secondary recrystallization. The annealing temperature above Ter weakens the sharpness of Goss oriented secondary. The results of secondary recrystallization behavior are explained in terms of the distribution of coincidence boundaries and their migration characteristics controlled by the intensity of the inhibitor.

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