Difference Between Graphene Oxide and Reduced Graphene Oxide

The key difference between graphene oxide and reduced graphene oxide is that the graphene oxide contains oxygen-containing functional groups whereas the reduced graphene oxide lacks the oxygen-containing functional groups.

Graphite oxide is a material that consists of carbon, hydrogen and oxygen atoms. We can obtain this compound by treating graphite with strong oxidizers. Also, we can produce the monomolecular sheets of this material, which is the graphene oxide sheets. Moreover, we can treat these monomolecular sheets to obtain reduced graphene oxide.

1. Overview and Key Difference
2. What is Graphene Oxide
3. What is Reduced Graphene Oxide
4. Side by Side Comparison – Graphene Oxide vs Reduced Graphene Oxide in Tabular Form
5. Summary

What is Graphene Oxide?

Graphene oxide is a monomolecular sheet from graphite oxide. This material is very important because we can use it to produce graphene sheets in an effective, yet inexpensive way. In this case, graphene oxide is an oxidized form of graphene. It has a single atomic layer, laced with oxygen-containing functional groups.

Difference Between Graphene Oxide and Reduced Graphene Oxide_Fig 01

Figure 01: Graphene Oxide Chemical Structure

This material is dispersible in water and other solvents due to the presence of oxygen-functionalities. Hence, it is easy to process this material. Also, this property enables it to enhance the electrical and mechanical properties of ceramic when we mix the ceramic material with graphene oxide. However, it is not good for electrical conductivity. Hence, we categorize it as an electrical insulator. Mainly, this is due to the disruption of sp² bonding networks that is present in graphite. But, there are some processes that we can use to augment its properties.

Also, there are four major methods that manufacturers use to make this compound. They are; Staudenmaier, Hofmann, Brodie, and Hummers method. These techniques have various differences between them.

Uses

In the production of transparent conductive films in flexible electronics, solar cells, chemical sensors, etc. by applying graphene oxide as a thin film deposited in the substrate.
For the replacement of tin oxide in batteries and touchscreens.
As an electrode material for batteries, capacitors and solar cells due to its high surface area.
To enhance the properties of composite materials (tensile strength, elasticity, conductivity, etc.) by mixing with those materials.
Various medical applications due to the fluorescent nature of the material.

What is Reduced Graphene Oxide?

Reduced graphene oxide is the reduced form of monomolecular graphene oxide sheets. There are no oxygen-containing functional groups since those groups are reduced via different treatment techniques. Also, this process of reduction is an extremely vital process because it has a large impact on the final product that we are going to get. Because, the process determines how close will be the quality of reduced form to the quality of perfect graphene.

For applications such as energy storage in large/industrial-scale, reduced graphene oxide is a good choice. It is mainly because, it is very easy to manufacture this compound in large scale than producing graphene.

Difference Between Graphene Oxide and Reduced Graphene Oxide_Figure 2

Figure 02: Absorbance Spectroscopy and Raman Spectroscopy of Graphite, Graphene Oxide and Reduced Graphene Oxide

There are several ways that we can reduce the graphene oxide to obtain reduced graphene oxide. Among them, the important techniques are thermal, chemical, or electrochemical methods. Using the chemical methods has a great advantage because, then we can scale-up the production as we wish. However, most of the times, the product from chemical methods has its electrical properties and surface area, below the standards.

Uses

In researches regarding graphene
Production of batteries
Biomedical applications
In the production of supercapacitors
In printable graphene electronics

What is the Difference Between Graphene Oxide and Reduced Graphene Oxide?

Graphene oxide is a monomolecular sheet of graphite oxide while reduced graphene oxide is the reduced form of monomolecular graphene oxide sheets. Hence, from this, we can understand the basis of the difference between graphene oxide and reduced graphene oxide. We can use graphene oxide to produce graphene in small-scale and in an inexpensive way, but we can use a reduced form of graphene oxide to produce graphene in large industrial scale.

Another difference between graphene oxide and reduced graphene oxide is that the graphene oxide is highly dispersible in water and other solvents while reduced form is less dispersible; it is dispersible at low concentrations. Above all, the key difference between graphene oxide and reduced graphene oxide is that the graphene oxide contains oxygen-containing functional groups whereas the reduced graphene oxide lacks the oxygen-containing functional groups. It is mainly because we produce the reduced form via reduction reactions of graphene oxide.

Summary – Graphene Oxide vs Reduced Graphene Oxide

In summary, the key difference between graphene oxide and reduced graphene oxide is that the graphene oxide contains oxygen-containing functional groups whereas the reduced graphene oxide lacks the oxygen-containing functional groups. Furthermore, we can convert graphite oxide into graphene oxide and then into reduced graphene oxide.

Reference:

1. “Graphene Oxide – What Is It?” Graphenea. Available here
2. “Reduced Graphene Oxide – What Is It? How Is It Created?” Graphenea. Available here

Image Courtesy:

1.”Graphene oxide”By Nothingserious (Public Domain) via Commons Wikimedia
2.”GrapheneOxide – Absorbance and Raman”By Krischkrisch – Own work, (CC BY-SA 4.0) via Commons Wikimedia