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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The combination of ultraviolet photoelectron spectroscopy and metastable helium induced electron spectroscopy is used to determine the density of states of the inner and outer coaxial carbon nanotubes. Ultraviolet photoelectron spectroscopy typically measures the density of states across the entire carbon nanotube, while metastable helium induced electron spectroscopy measures the density of states of the outermost layer alone. The use of double-walled carbon nanotubes in electronic devices allows for the outer wall to be functionalised whilst the inner wall remains defect free and the density of states is kept intact for electron transport. Separating the information of the inner and outer walls enables development of double-walled carbon nanotubes to be independent, such that the charge transport of the inner wall is maintained and confirmed whilst the outer wall is modified for functional purposes.

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