Effect of substrate type on structural and electrochemical performance of vertical graphene nanosheets deposited by HWP-CVD

Vertical graphene nanosheets (VGs) were synthesized on Cu, Ti, Si, and C substrates by helicon wave plasma chemical vapor deposition (HWP-CVD) method using CH₄/Ar as precursors. The obtained samples formed vertical orientation structures of nanosheets-graphene as the scanning electron microscopy and TEM images indicated. Specifically, the VGs grown on Cu substrate exhibit a parallel arrangement with a wall spacing of approximately 450 nm. This structural characteristic facilitates efficient ion exchange channels and promotes low resistance for electron transport. The effect of substrate type on the growth mechanism of VGs was discussed. The relationship between the microstructure and electrochemical performance of the VGs grown on different substrates was investigated. The charge transfer resistance of the VGs/Cu is 20.75 Ω, and the value of VGs/Ti, VGs/C and VGs/Si are 23.51 Ω, 33.76 Ω and 66.40 Ω, respectively. The robust vertical orientation structure of VGs holds promise for various applications, including catalyst support in fuel cells, conductive electrodes in photovoltaic cells, and energy storage devices like lithium-ion batteries and supercapacitors. This structural characteristic plays a pivotal role in advancing the development of next-generation energy storage technologies.