Researchers from China create graphene aerogel that converts sunlight into heat to produce water vapor at room temperature

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.

Graphene aerogel assists water treatment image

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.

GRAMOFON project aims to capture CO2 with the help of graphene aerogels

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.

Graphene oxide enables thermoacoustic speakers

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.

New method doubles performance of 3D printed supercapacitors

Researchers from Lawrence Livermore National Laboratory (LLNL) and UC Santa Cruz (UCSC) have designed a technique that could double the performance of 3D printed graphene-based supercapacitors. The new technique involves sandwiching lithium ion and perchlorate ion between layers of graphene in aerogel electrodes—a process which greatly improves the capacity of the electrodes while maintaining the high rate capability of the devices.

The 3D printing process used by the researchers to build the supercapacitors is a form of direct ink writing, consisting of two ion-intercalation steps before the hydrolysis of perchlorate ion intercalation compounds. According to the team “this two-step electrochemical process increases the surface area of graphene-based materials for charge storage, as well as the number of pseudo-capacitive sites that contribute additional storage capacity”.

New technique for 3D printing graphene aerogels could open door to new applications

Researchers at Kansas State University, University of Buffalo and the State University of New York have designed a new technique for 3D printing graphene aerogels with complex microstructures. The technique combines drop-on-demand 3D printing with freeze casting.

Aerogels are light and spongy materials that can be used as both thermal and optical insulators and can potentially be used as batteries and catalysts within electronic components. Recent years have brought about methods in which aerogels can be produced with certain 3D printers. The scientists have now developed a new 3D printing technique for producing graphene aerogels, which they hope will open up new uses for the material.

Versarien - Think you know graphene? Think again!Versarien - Think you know graphene? Think again!