Ultralight 3D Graphene Foams

By AZoNano

Table of Contents

Introduction
Synthesis of 3D Graphene Foams
Properties of CVD Grown Graphene Foams
Applications of 3D Graphene Foams
     Sensors
     Energy Storage
Commercial Availability of 3D Graphene Foams
About Graphene Supermarket

Introduction

Freestanding, ultra-lightweight graphene foams display a whole set of new and unique properties that add interest to graphene, the wonder material. Metal foam is being used by scientists to form a three-dimensional form of graphene termed as 3-D Graphene Foam. This material could be a promising candidate for chemical sensing and energy storage applications.

Synthesis of 3D Graphene Foams

The Graphene Foam (Figs. 1, 2) is produced by chemical vapor deposition (CVD). The CVD process for graphene involves introducing hydrogen and methane into a furnace heated to a temperature of 1000 °C. The heat developed in the furnace and the decomposition of methane result in the capture of a mono- or multi-layer of graphene by a copper or nickel film in the furnace. To form CVD Graphene foam, nickel foam is used instead of a thin nickel sheet.

The foam is subsequently etched away yielding a conductive, flexible, porous 3D Graphene Foam structure. This structure has a high surface area because of its many nanoscopic pores, which opens several exciting applications for Graphene Foam, while maintaining most of graphene two-dimensional properties. The nickel foam, which is used to create graphene foam is also made by CVD and has high-porosity. The applications of nickel foam and Graphene Foam are quite similar.

CVD processing of Graphene Foam is a cost-effective technique for engineering a novel class of ultra-light, highly conductive graphene-based materials with excellent mechanical strength, flexibility, and elasticity.

Figure 1. Freestanding Graphene Foam, low-resolution scanning electron microscopy (SEM).

Figure 2. Freestanding Graphene Foam, high-resolution scanning electron microscopy (SEM).

Properties of CVD Grown Graphene Foams

The electrical and structural properties of CVD grown Graphene Foam are excellent when compared to the properties of chemically derived reduced graphene oxide and few-layered graphene nanoplatelets. Both these materials have a large number of defects as well as poor interflake mechanical contact. In the above-mentioned materials, it is essential that several separate graphene sheets are actually connected with each other, whereas the CVD-grown Graphene Foam is monolithic. Additionally, reduced graphene oxide is inherently less conductive than graphene of which Graphene Foams are made of.

Applications of 3D Graphene Foams

3D Graphene Foams (Fig. 3) are used in the following applications:

  • Sensors.
  • Energy Storage.

Sensors

One essential application of Graphene Foam is in chemical sensing because of its high surface area. Graphene sensors made with Graphene Foam are 10 times more sensitive than those commercially available with the capability to sense 20 ppm of nitrogen dioxide. The graphene sensors can detect gases at room temperature whereas commercial sensors require high temperatures for proper functioning. The porous graphene is not only effective when compared to presently available sensors, but can also be reused. Graphene Foam requires just an electric shock to release the trapped gas molecules.

Energy Storage

Graphene Foam may also be used in energy storage applications, such as supercapacitors and batteries. The graphene foam structure helps storing huge amounts of energy. The Graphene Foam has a high surface area due to its porous nature, giving it a high electrochemical capacitance. Graphene, which is directly precipitated on nickel foam has good electrical contact with the nickel foam, further enhancing its performances as a supercapacitor. Graphene Foam on nickel was found to have a specific capacitance of 816 F g-1 at 5 mV s-1, which is relatively high when compared to other metal oxides.

Commercial Availability of 3D Graphene Foams

Three-dimensional CVD Graphene Foam is currently available at the Graphene Supermarket (Fig. 3). High-quality Graphene Foam is the latest product introduced and holds considerable potential for commercial applications. It is not just being considered for chemical sensing and energy storage, it also has potential applications including: supporting framework for catalysts, biological scaffolding and filters.

Figure 3. Freestanding Graphene Foam.

About Graphene Supermarket

The goal of Graphene Supermarket is to provide laboratory supplies for graphene community. Graphene Supermarket philosophy is to offer quality products, hassle-free shopping, easy order tracking and fast delivery. Graphene Supermarket has straightforward pricing, online shipping quote and checkout. Graphene Supermarket has no minimum order requirement for your convenience.

This information has been sourced, reviewed and adapted from materials provided by Graphene Supermarket.

For more information on this source, please visit Graphene Supermarket.

Date Added: Apr 17, 2012 | Updated: Jun 11, 2013
Ask A Question

Do you have a question you'd like to ask regarding this article?

Leave your feedback
Submit