Graphene Foam: Introduction and News - Page 3

Researchers at Rice University have constructed a graphene foam, reinforced by carbon nanotubes, that can support more than 3,000 times its own weight and bounce back to its original height. In addition, its shape and size are easily controlled - which the team demonstrated by creating a screw-shaped piece of the material.

The 3D structures were created from a powdered nickel catalyst, surfactant-wrapped multiwall nanotubes and sugar as a carbon source. The materials were mixed and the water evaporated; the resulting pellets were pressed into a steel die and then heated in a chemical vapor deposition furnace, which turned the available carbon into graphene. After further processing to remove remnants of nickel, the result was an all-carbon foam in the shape of the die, in this case a screw. The team said the method will be easy to scale up.

Researchers at Washington University have managed to use graphene oxide sheets to create a biofoam that can transform dirty water into drinking water. Their hope is that in countries where there is a lot of sunlight, it'll be possible to take dirty water, evaporate it using this material, and collect fresh water.

This new method combines bacteria-produced cellulose and graphene oxide to form a bi-layered biofoam. The production process is said to be extremely simple, and the nanoscale cellulose fiber network produced by bacteria has excellent ability to move the water from the bulk to the evaporative surface while minimizing the heat coming down. The material is a bi-layered structure with light-absorbing graphene oxide filled nanocellulose at the top and pristine nanocellulose at the bottom. When suspended this on water, the water is actually able to reach the top surface where evaporation happens.

A team of researchers from Boise State University have conducted a study that focuses on demonstrating the suitability of graphene foam (3D version of graphene) as a scaffold for growing functional muscle tissue. In the future, researchers hope that the unique properties of graphene and graphene foam can be used to regenerate 3-dimensional tissues and organs for implantation into the human body.

According to the team, the study demonstrated that extra cellular matrix proteins on graphene foam can enhance the differentiation of pluripotent C2C12 myoblasts,and in addition it was possible to verify muscle functionality by using the graphene foam itself as an electrode to stimulate the tissue.

Graphene 3D Lab has announced Graphene Flex Foam, a new commercial product that will be available through Graphene Laboratories’ e-commerce site, Graphene Supermarket. The new product is described as a Multilayer Freestanding Flexible Graphene Foam, that brings together a conductive elastomer composite with ultra-light graphene foam.

The foam, a highly conductive 3D chemical vapor deposition (CVD), together with the composite, brings together the best of several worlds of graphene usage. As a flexible foam, the material is both lightweight and reconfigurable, adding to ease of use and handling, with a porous structure. The Graphene Flex Foam could be used in conjunction with other graphene-related materialssuch as Graphene 3D Lab’s filament offeringsin the creation of electronics and other conductive products.

Researchers at the University of Aveiro in Portugal designed unique "tea bags" using a porous graphene oxide foam, which they say can help purify water by removing dissolved mercury. These foams demonstrate several significant advantages over existing water purification systems: they are reusable, simple to synthesize and should be easy to produce in bulk at a relatively low cost. The scientists add that they are also not affected by pH, which is beneficial since other sorbents often need the pH to be optimized, which drives up costs.

The scientists heated graphene oxide with ammonia to create a porous 3D material with a high surface area. After screening their materials for their ability to adsorb various toxic pollutants, the team chose to focus on mercury, one of the top three on the EU’s priority list of hazardous substances in water. The "tea bag" form was chosen due to the fact that the foam sometimes broke apart, and also to optimize contact with water.

Researchers at the Harbin Institute of Technology in China and the University of Michigan in the US demonstrated improved LFP battery cathode, augmented by reduced graphene oxide. The scientists used reduced graphene oxide (rGO) in LFP battery cathodes to create a new high surface area 3D composite.

LFP (or LiFePO4) is a kind of Li-Ion rechargeable battery for high power applications, such as electric vehicls, Power Tools and more. LFP cells feature high discharging current, non explosive nature and long cycle life, but its energy density is lower than normal Li-Ion cell. In this study, the researchers created the composite using a nickel foam template that was coated with layers of graphene oxide. The graphene oxide reduced as the LFP nanoparticles were synthesized in a simple technique that allows larger amounts of the LFP to be loaded into the carbon material.

Researchers at Stanford University developed a new battery technology based on graphene and aluminum. The stanford team claims that their aluminum battery has a number of advantages over lithium: it's flexible, can be charged in a minute instead of hours and is very durable. it's also cheaper and non-reactive (meaning compromising it will not result in sparks like lithium batteries).

The scientists used graphene foam (made by creating a metal foam, then catalyzing graphene formation on its surface) as cathode material and aluminum foil as the anode. The electrolyte the researchers used was a solution of aluminum trichloride dissolved in an organic solvent that also contained chlorine. While this granted better performance (7,500 cycles, much more than the 1,000 expected from a Li-ion battery), the voltage provided by an aluminum-ion battery is only about half of that what you'd get from a lithium-ion cell. Also, the overall power density (the amount of power you can store in a battery in relation to its size) is still insufficient.

Researchers at the Rice University have devised a process in which a computer-controlled laser burns through a polymer to create flexible, patterned sheets of multilayer graphene that may be suitable for electronics or energy storage. The process works in air at room temperature, cancelling the need for hot furnaces and controlled environments.

The product of this process is not a 2D piece of graphene but a porous foam of interconnected flakes about 20 microns thick. The laser doesn't cut all the way through the base material, so the foam remains attached to a flexible plastic base.

An annual photo competition held by faculty of engineering at the University of Cambridge aims to present the wide variety of engineering research at the university. This year, the winner of this competition was an incredible electron micrograph photo of free-standing graphene foam.

The graphene foam was made by growing a few layers of graphene on the surface of a porous metal foam skeleton (by CVD), then removing it by dissolving it in etching solution. The photo, by Adrianus Indrat Aria, was called Asteroidea Electrica.

Researchers from Stockholm University managed to develop a super-insulating and fire retardant foam for house insulation by freezing together graphene oxide, cellulose nanofibers and clay nanorods.

The foam is highly porous and boasts lower thermal conductivity than traditional insulators like polystyrene and polyurethane. It is mechanically stiff, able to sustain great loads and also does not need to be laced with organic fire retardants (it is inherently fire retardant). The researchers believe this foam could even be fitted onto older buildings without tampering with their appearance.