Literature Seminar Abstract
Vertically-aligned carbon nanostructures (VACNs) have many potential applications resulting from their mechanical and thermal stability, high surface area, high conductivity, and their ability to be chemically functionalized. Traditionally, VACNs have been produced via thermal chemical vapor deposition (CVD) or arc discharge. Thermal CVD is energy intensive, generally requiring processing temperatures above 600 °C.1 Plasma-enhanced CVD (PECVD) is a highly tunable synthetic method that can be employed to address this challenge by using plasma processing to generate reactive species at lower processing temperatures. Pulsed PECVD (PPECVD) is a power-modulated technique that can be used to generate plasmas with different synthetic properties compared to PECVD. The formation of multi-walled carbon nanotubes (CNTs) and vertical graphene nanosheets (VGNs) will be discussed.2 CNTs are characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy, and optical emission spectroscopy provides information on the plasma.2 In addition to the above techniques, the composition and binding environments of the VGNs are assessed via X-ray photoelectron spectroscopy (XPS). Overall, PPECVD enhances the growth of VACNs when compared to PECVD. A critical analysis of results is offered with an emphasis on the potential use of PPECVD to produce VACNs for energy storage applications.
1. Chen, H.; Roy, A.; Baek, J.; Zhu, L.; Qu, J.; Dai, L. Controlled Growth and Modification of Vertically-Aligned Carbon Nanotubes for Multifunctional Applications. Mater. Sci. Eng. R 2010, 70, 63-91.
2. Baro, M.; Gogoi, D.; Pal, A. R.; Adhikary, N. C.; Bailung, H.; Chutia, J. Pulsed PECVD for Low-Temperature Growth of Vertically Aligned Carbon Nanotubes. Chem. Vap. Deposition 2014, 20, 161–169.