Microwave plasma-enhanced chemical vapor deposition growth of graphene nanowalls on varied substrates: A comparative study.

We explored the growth rate and morphological characteristics of graphene nanowalls (GNWs) on copper (Cu), stainless steel (SUS), quartz and silicon (Si) substrates by changing the growth time using microwave plasma-enhanced chemical vapor deposition (MWPCVD). Furthermore, we investigated the impact of catalytic and non-catalytic substrates on the growth features of GNWs. The properties of GNWs were characterized using scanning electron microscopy (SEM) and Raman spectroscopy. The growth of GNWs occurred just after supplying the precursor on the Cu substrate, but those on SUS, quartz and Si delayed about 5 min, 10 min and 15 min, respectively, due to the low catalytic activity of the substrate. Once the growth started, there was not much of a difference in the growth rate. The average growth rate was about 2 nm/s. The crystallinity of GNW was improved with increasing growth time. It was found that Cu is the best substrate to get high-quality GNWs, but MWPCVD is a suitable technique to obtain GNWs on a variety of substrates at relatively low temperatures. [ABSTRACT FROM AUTHOR]