Rapid Synthesis in a Microcombustion Environment and Transfer Process Development for Few Layer Graphene

Abstract

Graphene is a nanomaterial that consists of a carbon monolayer (one atom thick) arranged in the graphitic structure. Since the 2004 discovery of graphene as a material useful for applications using nanotechnology, there has been significant interest in the synthesis and applications of graphene. Possible applications focus on areas that utilize the excellent properties of graphene for high electrical conductivity, stronger composite materials, and increased rate of fluid flow through graphene. However, current methods for synthesis are either not easily scalable for industrial production or require complex, slow, and expensive methods. Recent work has shown that microcombustion presents a novel, rapid, and efficient method for targeted graphene synthesis. The objective of this undergraduate honors project is to deposit few layer graphene (FLG) on Cu (copper) wires and then transfer these to a silicon substrate for application in a biosensor towards prostate cancer cell detection. Several experimental methods for transferring FLG layers from Cu wires were compared and evaluated. After each test, Si samples were analyzed using Raman spectroscopy to check for chemical integrity and scanning electron microscopy (SEM) to identify size and structure. Each method had pros and cons. For instance, chemical etching of Cu wires adhered to Si substrates with adhesive led to Si fouled by etched particles and adhesive residue. Attempts to dissolve the adhesive by solvent treatment led to encapsulation of FLG layers with the adhesive. Sonicating Cu wires to release FLG followed by filter collection has shown ability to collect small flakes with size yet to be determined. Unfortunately, filter capture requires a high degree of precision and an elaborate set-up to achieve successful transfer. Due to these obstacles, successful transfer and implementation of FLG into an application was not achieved. Additional work is required to further the work and results seen in the project and create a robust transfer process for the FLG flakes.