SYNTHESIS AND DEPOSITION OF GRAPHENE THIN FILMS USING MODIFIED HUMMERS CHEMICAL EXFOLIATION METHOD

• Main Author: TRIMADYA PUTRA ( NIM :10510016) ; Pembimbing Dr. Veinardi Suendo, ARIA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/18041
• Institution: Institut Teknologi Bandung

Nowadays, transparent conductors are intensively used in many electronic devices for various <br /> <br /> <br /> <br /> <br /> <br /> <br /> applications such as touch screens and thin film displays. Graphene is a two dimensional (2D) <br /> <br /> <br /> <br /> <br /> <br /> <br /> carbon material with a honeycomb-like structure that has potential as a transparent conductor <br /> <br /> <br /> <br /> <br /> <br /> <br /> with high electrical and thermal conductivity, as well as good mechanical properties. This <br /> <br /> <br /> <br /> <br /> <br /> <br /> research has been conducted on the modification graphene synthesis using chemical <br /> <br /> <br /> <br /> <br /> <br /> <br /> exfoliation based on the method developed by Hummers. Modifications include the burning <br /> <br /> <br /> <br /> <br /> <br /> <br /> step of graphite samples at temperatures of 1000 &#730;C to reduce the amorphous phase, as well as <br /> <br /> <br /> <br /> <br /> <br /> <br /> replacing the oxidizer on each stage of oxidation processes. The first modification is to burn <br /> <br /> <br /> <br /> <br /> <br /> <br /> of graphite by flame at 1000 &#730;C, the second modification is replacing NaNO3 oxidant by <br /> <br /> <br /> <br /> <br /> <br /> <br /> Ammonium peroxodisulfate (APS), the third modification is replacing KMnO4 oxidant by <br /> <br /> <br /> <br /> <br /> <br /> <br /> APS, and the fourth is to replace H2O2 oxidant by APS. Graphite oxide obtained from synthesis <br /> <br /> <br /> <br /> <br /> <br /> <br /> steps above, subsequently sonicated at room temperature to obtain graphene oxide dispersions <br /> <br /> <br /> <br /> <br /> <br /> <br /> in water. All the modifications have been managed to turn graphite into graphene oxide. This <br /> <br /> <br /> <br /> <br /> <br /> <br /> is proven by the typical Raman peak of graphene oxide namely the G band with low intensity <br /> <br /> <br /> <br /> <br /> <br /> <br /> at ~1591 cm- 1 and the D band with higher intensity at ~1310 cm- 1. UV – Vis absorption spectra <br /> <br /> <br /> <br /> <br /> <br /> <br /> of graphene oxide dispersions in water show the absorption band at ~230 nm corresponds to <br /> <br /> <br /> <br /> <br /> <br /> <br /> the &#960; - &#960;* transition of the C=C bonds and at ~300 nm corresponds to n - &#960;* transition of the <br /> <br /> <br /> <br /> <br /> <br /> <br /> carbonyl functional group in graphene oxide. Modified graphene oxide was reduced into <br /> <br /> <br /> <br /> <br /> <br /> <br /> graphene using phenylhydrazine on metal surface. Raman spectra of the graphene samples <br /> <br /> <br /> <br /> <br /> <br /> <br /> give similar features to graphene oxide but with narrower peaks, which indicate an increase in <br /> <br /> <br /> <br /> <br /> <br /> <br /> their crystallinity.