Graphene Aerogel: Introduction and Market News - Page 4

Researchers at Zhejiang University in China have designed a new type of aerogels, made of graphene and carbon nanotubes, that can be reversibly stretched to more than three times their original length, displaying elasticity similar to that of a rubber band. This stretchability, in addition to aerogels' existing properties like ultralow density, light weight, high porosity, and high conductivity, may lead to exciting new applications.

The scientists designed carbon aerogels consisting of both graphene and multi-walled carbon nanotubes assembled into four orders of hierarchical structures ranging from the nanometer to centimeter scale. To fabricate the material into aerogels, the researchers created an ink composed of graphene oxide and nanotubes, and then formed the aerogels via inkjet printing.

The PolyGraph project, a 4-year development project with aims to develop new production techniques to deliver industrial scale quantities of graphene-reinforced thermosetting polymers, has published its results.

The POLYGRAPH (Up-Scaled Production of Graphene Reinforced Thermosetting Polymers for Composite, Coating and Adhesive Applications) project brought together 14 partners, including SMEs, companies, universities and a research center, and has reportedly led to the identification of the most suitable materials and production techniques for graphene-based coatings, adhesives and composites. Once the graphene market reaches maturity and material prices drop , these new products could appeal to a vast range of industries.

A research team from the Paul Scherrer Institute in Switzerland and Sapienza University in Rome developed a new loud speaker that is driven by a light signal - and without electricity. The idea is to use modulated light that shines on a 3D graphene sponge. The audio is achieved via a highly-efficient photo-mechanism.

The researchers say that unlike conventional loudspeakers, this high-fidelity photo-speaker does not rely on vibrations to produce the sound - and it does not need any type of electrical connection or complicated system for sound generation. Using an optical pulse train, this loudspeaker allows a completely digital operation for frequencies from acoustic to ultrasound.

Imagine Intelligent Materials and Swinburne University have announced a collaborative six-month project aiming to develop graphene-reinforced smart composites. The composite will be able to report on the condition of large structures, and will have major commercial potential in the transport sector, including automotive and aerospace.

The project is supported by a $20,000 Seed grant from the university under a program, targeting interdisciplinary projects that are aligned with the Swinburne research institutes’ external partnership and collaboration objectives. It will combine expertise from experts in sensors, electronics engineering and aerospace manufacturing at the university.

A collaboration work by Purdue, the Chinese Lanzhou University and Harbin Institute of Technology, and the U.S. Air Force Research Laboratory has yielded a lightweight, flame-resistant and super-elastic composite shown to combine high strength with electrical conductivity and thermal insulation, suggesting potential applications from buildings to aerospace.

The composite material is made of interconnected cells of graphene sandwiched between ceramic layers. The graphene scaffold, referred to as an aerogel, is chemically bonded with ceramic layers using a process called atomic layer deposition. The team explained that graphene would ordinarily degrade when exposed to high temperature, but the ceramic imparts high heat tolerance and flame-resistance, properties that might be useful as a heat shield for aircraft. The light weight, high-strength and shock-absorbing properties could make the composite a good substrate material for flexible electronic devices. Because it has high electrical conductivity and yet is an excellent thermal insulator, it might be used as a flame-retardant, thermally insulating coating, as well as sensors and devices that convert heat into electricity, said associate professor in the School of Industrial Engineering at Purdue University.

Guiness World Records has named a 3D printed graphene aerogel as "the least dense 3D printed structure". The 3D printed graphene aerogel, developed by a Kansas State University, University at Buffalo and Lanzhou University (China) team, weighs 0.5 milligrams per cubic centimeter. This achievement will be featured in the GUINNESS WORLD RECORDS 2018 Edition.

The way the researchers print the three-dimensional graphene is also regarded as revolutionary. The researchers use a modified inkjet printer that uses two nozzles. They 3D print droplets of a graphene oxide and water mixture in a freezer on a cold plate that is minus 20 degrees Celsius. This method creates a 3D ice structure of graphene and frozen water, which helps the graphene to maintain its shape.

Researchers at Zhejiang University in China have designed a graphene-based aerogel mimicking the structure of the "powdery alligator-flag" plant that could have potential for use in applications like flexible electronics.

The team drew inspiration from the stem structure of the powdery alligator-flag plant (Thalia dealbata), a strong, lean plant capable of withstanding harsh winds. The researchers used a bidirectional freezing technique that they previously developed to assemble a new type of biomimetic graphene aerogel that had an architecture like that of the plant's stem. When tested, the material supported 6,000 times its own weight and maintained its strength after intensive compression trials and was resilient. They also put the aerogel in a circuit with a LED and found it could potentially work as a component of a flexible device.

Researchers at the Chinese Hubei University have designed a graphene aerogel film capable of producing water vapor at room temperature using only sunlight. The aerogel floats on the surface, where it heats up only a small part of the water column, ‘while the temperature of the bulk water is far below the boiling point’, the team explains.

This sunlight-harvesting graphene film could convert sea or wastewater into drinking water in places where fuel or access to electricity is limited. Desalinating seawater to make it drinkable usually means boiling it, and then collecting and condensing the steam. Heating water to its boiling point, however, requires quite a lot of energy, which is not always easy to come by. There are solar stills that desalinate water using only sunlight, but they’re slow and not always efficient enough to provide sufficient drinking water for a person’s daily needs.

Project GRAMOFON, a 3.5 year project that started in October 2016, aims to establish a process for efficient CO2 capture by innovative adsorbents based on modified graphene aerogels and MOF materials. The EU will contribute nearly €4.2 million to the project.

The key objectives of GRAMOFON projects are:

• to develop and prototype a new energy and cost-competitive dry separation process for post-combustion CO2 capture based on innovative hybrid porous solids Metal organic frameworks (MOFs) and Graphene Oxide nanostructures.
• to optimize the CO2 desorption process by means of Microwave Swing Desorption (MSD) and Joule effect, that will surpass the efficiency of the conventional heating procedures.

Researchers at Korea Advanced Institute of Science and Technology (KAIST) have developed a new graphene oxide-based speaker design said to be specifically targeted for the mobile audio market. The speaker does not require an acoustic box to produce sound.

The researchers used graphene in a relatively simple, two-step process that yielded a thermoacoustic speaker. Thermoacoustics is based on the idea that sound can be produced by the rapid heating and cooling of a material instead of through vibrations.