Hailong Hu

Improved field emission properties of CuO nanowire arrays by coating of graphene oxide layers

Graphene oxide (GO)-coated copper oxide (CuO) nanowire arrays were prepared as field emission cathodes using a solution process, in which CuO nanowires were grown on Cu substrates by a low-temperature hydrothermal process and the covering of GO sheets was carried out using an electrostatic self-assembly method. The field emission investigations of GO/CuO cathode showed a low turn-on field of 3.7 V/μm and a high enhancement factor (2080) compared to those of bare CuO nanowires. Furthermore, the emission current was stable without any attenuation during the testing. The GO/CuO composite nanostructures are promising field emission cathodes in field emission application.

Field emission characteristics of graphene oxide coated CuO cathode

Graphene oxide (GO) coated CuO nanoswire arrays have been prepared on Cu substrate as field emission cathodes. CuO were grown on Cu substrates by a low-temperature hydrothermal process and the covering of GO sheets was carried out using an electrostatic self-assembly method. The field emission (FE) investigation of GO/CuO cathode showed a low turn-on field (4.5 V/ μ m) and high enhancement factor (1190) compared to those of pure CuO. The GO/CuO composite nanostructures are promising field emission cathodes in FE application.

Monodisperse and 1D Cross-Linked Multi-branched Cu @ Ni Core–Shell Particles Synthesized by Chemical Reduction

We report on a two-step wet chemical route for producing Cu@Ni core–shell particles with multiple needle-like branches on the surface. Using the usual synthesis process, urchin-like Ni shells were formed on the surface of spherical Cu cores and monodisperse particles were obtained. Under the direction of a static magnetic field, one-dimensional, well-aligned Cu@Ni particles were assembled through cross-linking the branched Ni shells. The monodisperse Cu@Ni particles show stable and uniform field electron emission, having a low turn-on field of 3.3 V/μm and a large current density of 1 mA/cm2 under an applied field of about 5.33 V/μm.