Tunable synthesis of carbon nanosheet/silicon nanowire hybrids for field emission applications

Carbon nanosheets (CNSs) were synthesized on silicon nanowires (SiNWs) using microwave plasma enhanced chemical vapor deposition without any catalyst. The synthesized products are composed of graphene and graphite nanosheets, and the ratio of the two kinds of nanosheets depends on the growth conditions. The morphology of CNS/SiNW hybrids can be controlled by adjusting growth time, microwave power and carbon concentration. The field emission performances of the hybrids are greatly improved compared to that of the as-prepared SiNWs. The turn-on field at 10 μA cm− 2, applied field at 1 mA cm− 2 and field enhancement factor of the hybrids with optimal morphology are 3.0 V μm− 1, 4.2 V μm− 1 and 1612, respectively. The improvements of field emission properties are mainly attributed to the high-density separated CNSs with sharp edges.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Carbon nanosheets were synthesized on the as-prepared Si nanowires by microwave PECVD. ► The morphology of the carbon nanosheet/Si nanowire hybrids can be controlled. ► The carbon–nanosheet-coated Si nanowires perform much better field emission properties.