Large scale N-doped GNTs@a-SiOx(x=1–2)NPs: template-free one-step synthesis, and field emission and photoluminescence properties

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2019-01, Vol.7 (13), p.3756-3764
• Main Authors: Li, Z J, Qiu, G H, Zhang, J H, Song, G Y, Lin, Y S, Meng, A L, Li, Q D
• Format: Article
• Language: English
• Subjects: Electric fields; Field emission; Graphene; Lattice vacancies; Morphology; Nanocomposites; Nanoparticles; Nanotubes; Photoluminescence; Properties (attributes); Raw materials; Silicon dioxide; Synergistic effect; Synthesis
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/c8tc06614k

N-doped graphene nanotubes coated by amorphous SiOx(x=1–2) nanoparticles (N-doped GNTs@a-SiOx(x=1–2)NPs) were synthesized by a simple template-free one-step calcination method. The method not only possesses a simple synthesis process, but also protects the graphene nanotubes from damage caused by template removal. The characterization results show that amorphous SiOx(x=1–2) nanoparticles with a size of 20–40 nm were located on the surface of the N-doped graphene nanotubes. The product synthesized under the optimal molar ratio of raw materials (C3H6N6: Si/SiO2 powders = 1 : 2) presents a lower turn-on electric field of 0.663 V μm−1, and especially, a very low threshold electric field of 1.575 V μm−1 (at 10 mA cm−2 current density). Moreover, it also showed improved intensity of yellow-green emission compared with N-doped GNTs. The reason for the outstanding performance of N-doped GNTs@a-SiOx(x=1–2)NPs was attributed to the synergistic effect of N-doping, a large number of oxygen vacancy defects of SiOx(x=1–2), and the unique morphology. The research results not only provide a new method for large-scale synthesis of N-doped GNTs@a-SiOx(x=1–2)NPs nanocomposites with excellent field emission properties and photoluminescence properties, but also lay the foundation for their applications in various fields.