Controllable synthesis of a novel hedgehog-like core/shell structure

• Published in: Journal of solid state chemistry 2012-02, Vol.186, p.235-239
• Main Authors: Wang, Shumin, Tian, Hongwei, Pei, Yanhui, Meng, Qingnan, Chen, Jianli, Wang, Huan, Zeng, Yi, Zheng, Weitao, Liu, Yichun
• Format: Article
• Language: English
• Subjects: CARBON; CHEMICAL COATING; Chemical synthesis methods; CHEMICAL VAPOR DEPOSITION; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); COPPER; Copper particles; Cross-disciplinary physics: materials science; rheology; DEPOSITION; ELECTRON MICROSCOPY; ELEMENTS; EMISSION; Exact sciences and technology; FIELD EMISSION; Fullerenes and related materials; diamonds, graphite; Graphene; Graphene encapsulated copper; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; LAYERS; MATERIALS; Materials science; METALS; Methods of deposition of films and coatings; film growth and epitaxy; Methods of nanofabrication; MICROSCOPY; MORPHOLOGY; Multilayers; NONMETALS; PARTICLES; Physics; RF-PECVD; Scanning electron microscopy; Shells; Specific materials; Stability; SURFACE COATING; SURFACES; SYNTHESIS; TRANSITION ELEMENTS; TRANSMISSION ELECTRON MICROSCOPY
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2011.12.019

A novel hedgehog-like core/shell structure, consisting of a high density of vertically aligned graphene sheets and a thin graphene shell/a copper core (VGs-GS/CC), has been synthesized via a simple one-step synthesis route using radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD). Scanning and transmission electron microscopy investigations show that the morphology of this core/shell material could be controlled by deposition time. For a short deposition time, only multilayer graphene shell tightly surrounds the copper particle, while as the deposition time is relative long, graphene sheets extend from the surface of GS/CC. The GS can protect CC particles from oxidation. The growth mechanism for the obtained GS/CC and VGs-GS/CC has been revealed. Compared to VGs, VGs-GS/CC material exhibits a better electron field emission property. This investigation opens a possibility for designing a core/shell structure of different carbon–metal hybrid materials for a wide variety of practical applications. With increasing deposition time, graphene sheets extend from the surface of GS/CC, causing the multilayer graphene encapsulated copper to be converted into vertically aligned graphene sheets–graphene shell/copper core structure. [Display omitted] ► A novel hedgehog-like core/shell structure has been synthesized. ► The structure consists of vertical graphene sheets-graphene shell and copper core. ► The morphology of VGs-GS/CC can be controlled by choosing a proper deposition time. ► With increasing deposition time, graphene sheets extend from the surface of GS/CC. ► VGs-GS/CC exhibits a better electron field emission property as compared with VGs.