CVD Grown Mwcnts and Graphene for Pemfcs Application

In this paper we report the development of Multi-Walled Carbon Nanotubes (MWCNTs) and graphene via chemical vapor deposition (CVD) for PEM Fuel Cells applications. MWCNTs growth are achieved by the flow of ethylene and hydrogen gasses over iron beased catalytic substrates at different temperatures and gas flow. Graphene growth is carried out by the flow of methane and hydrogen gasses over various thickness cupper substrates cleaned by different methods (electropolishing, acetone and acetic acid) at low (500 mTorr) and atmospheric pressure. Characterization is performed with XRD, optical microscopy (SEM/EDS) and Raman/AFM spectroscopy. Results show noticeable differences in Raman signals and optical color contrast regarding the preferential growth of MWCNTs, and between the number and quality of layers of graphene and graphite, as well as distinctions between single-to-few- and multi-layer graphene, respectively. The electrochemical behavior of CVD grown MWCNTs and graphene are studied by cycling voltammetry on rotating disk electrode (RDE) to determine the activity of toward oxygen reduction reaction (ORR). Scanning Electrochemical Microscopy (SECM) is used to shows the localized electrochemical behavior difference between the MWCNTs and graphenes.