Comparative Morphological Analysis of Graphene on Copper Substrate obtained by CVD from a Liquid Precursor

Abstract

Graphene film has been produced on untreated Cu substrate by a chemical vapor deposition technique in ambient pressure with liquid ethanol serving as the carbon precursor. The obtained material has been subjected to morphological study, directly on Cu substrate, by means of optical microscopy, scanning electron microscopy, atomic force microscopy, and a detailed Raman analysis. As a benchmark material, graphene obtained on Cu by a conventional CVD from gaseous methane was used. This simple experimental setup has proved to enable obtaining large area graphene samples with nearly 100% substrate coverage and large domains of one carbon layer. As compared to graphene from gaseous precursor, the presented approach resulted in visibly more defects and impurities. These imperfections are due to more complex precursor molecular structure and lack of Cu pretreatment with hydrogen, the later cause being easy to eliminate in course of further optimization of the method. The described approach can be regarded as a viable, low-cost, and experimentally simple alternative for the existing techniques of producing large area graphene. By providing direct comparison with the conventional method, the paper's intention is to provide deeper insight and to fill gap in the understanding of mechanisms involved in graphene formation on copper.

Synthesis of Large-Area Single-Layer Graphene Using Refined Cooking Palm Oil on Copper Substrate by Spray Injector-Assisted CVD

“…Many benign alternative attempts have been made to replace these typical precursors with moderate hazardous hydrocarbon supplied from liquid or solid carbon sources. For an example, Weiss et al investigated the growth of graphene on copper (Cu) substrate by utilizing ethanol [19]. Choi et al reported the growth in oxidized ambient by using a combination of ethanol and methanol as a carbon source [20].…”