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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