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Broadband absorbers derived from metal−organic frameworks are highly desirable in the electromagnetic (EM) wave absorption field. Herein, a strategy for cobalt-decorated porous ZrO 2 /C hybrid octahedrons by pyrolysis of Co(NO 3 ) 2impregnated NH 2 -UIO-66 was developed. The hybridization of Co nanoparticles with ZrO 2 /C results in remarkable EM wave absorption performance with a minimum reflection loss (RL) of −57.2 dB at 15.8 GHz, corresponding to a matching thickness of 3.3 mm. The maximum effective absorption bandwidth (RL ≤ −10 dB) reaches 11.9 GHz (6.1−18 GHz), covering 74.4% of the whole measured bandwidth. The textural properties of nanocomposites have been thoroughly characterized by powder Xray diffraction, electron microscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption−desorption isotherms. The corresponding results show that the face-centered cubic-phased ∼50 nm Co nanoparticles are evenly distributed on the surface of porous ZrO 2 /C hybrid octahedrons. The excellent performance of Co/ZrO 2 /C can be ascribed to the strong interface polarization and the suitable impedance matching, originating from the synergistic effect among the components.

Vertical GaAs nanowires on Si (111) substrate were grown by metal organic chemical vapor deposition via Au-catalyst vapor-liquid-solid mechanism. Stacking-faults-free zinc blende nanowires were realized by using AlGaAs/GaAs buffer layers and growing under the optimized conditions, that the alloy droplet act as a catalyst rather than an adatom collector and its size and composition would keep stable during growth. The stable droplet contributes to the growth of stacking-faults-free nanowires. Moreover, by using the buffer layers, epitaxial growth of well-aligned NWs was not limited by the misfit strain induced critical diameter, and the unintentional doping of the GaAs nanowires with Si was reduced.

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In this study, we chose highly-elastic fabric fibres as the functional carrier and then simply coated the fibres with reduced graphene oxide (rGO) using plasma treatment, dip coating and hydrothermal reduction steps, finally making a wearable strain sensor. As a result, the full-scale detection of human motions, ranging from bending joints to the pulse beat, has been achieved by these sensors. Moreover, high sensitivity, good stability and excellent repeatability were realized. The good sensing performances and economical fabrication process of this wearable strain sensor have strengthened our confidence in practical applications in smart clothing, smart fabrics, healthcare, and entertainment fields.

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InAs quantum dots (QDs) are grown epitaxially on Au-catalyst-grown GaAs nanowires (NWs) by metal organic chemical vapor deposition (MOCVD). These QDs are about 10-30 nm in diameter and several nanometers high, formed on the {112} side facets of the GaAs NWs. The QDs are very dense at the base of the NW and gradually sparser toward the top until disappearing at a distance of about 2 μm from the base. It can be concluded that these QDs are formed by adatom diffusion from the substrate as well as the sidewalls of the NWs. The critical diameter of the GaAs NW that is enough to form InAs QDs is between 120 and 160 nm according to incomplete statistics. We also find that these QDs exhibit zinc blende (ZB) structure that is consistent with that of the GaAs NW and their edges are faceted along particular surfaces. This hybrid structure may pave the way for the development of future nanowire-based optoelectronic devices.