A 3D catalyst electrode is fabricated by layer‐by‐layer assembly of 2D WS2 nano­layers and P, N, O‐doped graphene sheets into a heterostructured film. The film exhibits remarkable hydrogen evolution performance, benefitting from the utmost exposed active centers on 2D nanolayers, highly expanded surface, and continuous conductive network, as well as strong synergistic effects between the components.

Existing wireless ad hoc routing protocols typically find routes with the minimum hop-count. This paper presents experimental evidence from two wireless test-beds which shows that there are usually multiple minimum hop-count paths, many of which have poor throughput. As a result, minimum-hop-count routing often chooses routes that have significantly less capacity than the best paths that exist in the network. Much of the reason for this is that many of the radio links between nodes have loss rates low enough that the routing protocol is willing to use them, but high enough that much of the capacity is consumed by retransmissions. These observations suggest that more attention be paid to link quality when choosing ad hoc routes; the paper presents measured link characteristics likely to be useful in devising a better path quality metric.

Graphene single and multilayers were investigated for the first time with metastable induced electron spectroscopy (MIES). MIES is only sensitive to the electronic structure of the outermost layer and thus the substrate does not contribute to the spectra. It has been shown that the electronic structure of graphene changes with the number of layers and can be correlated to the band structure calculations. Angle resolved x-ray photoelectron spectroscopy in combination with Raman spectroscopy were employed to determine the thickness and the structure of the graphene samples and their defect density. We demonstrate that MIES can be used to measure directly the electronic density of states in graphene samples, which correlates to their structural characteristics such as number of layers and presence of defects.

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