Reduced graphene oxide: an introduction - Page 4

Researchers from Southeast University and Suzhou University of Science and Technology in China have combined the properties of graphene and paraffin to create a novel material that exhibits controllable, reversible transition between a slippery and a rough surface. They fabricated a graphene-based film with a porous surface filled with paraffin that allows droplets of water and other fluids to stick or slide on demand, while following complicated pathways.

The research team used near-infrared (NIR) laser irradiation to control the surface behavior of the film and form patterned flow pathways on it. Their work can simplify the manipulation of liquids inside microplates that are extensively used for bioassays in biomedical and clinical laboratories; it may also prove to be a valuable tool for blood grouping diagnosis.

A new consortium (called the Graphene REACH registration consortium) was launched in 2017 to handle REACH graphene registration in the EU. The consortium members, The Sixth Element Material Technology, NanoXplore and Applied Graphene Materials announced that the joint registration dossiers for graphene and graphene oxide have been submitted to the ECHA.

The consortium is also preparing a JRD for reduced graphene oxide, and hopes to submit it before the end of 2018. The consortium issues a callout for companies (whether graphene producers or importers) to join the consortium or buy a letter of access to the new registrations.

A team of researchers from The University of Texas at Austin and University of California in the US, along with teams from the University of Electronic Science and Technology, Hunan University and Soochow University in China, report the design of a negatively charged graphene composite separator for the effective suppression of the polysulfide shuttling effect in Li-sulfur batteries. The negatively charged 3D porous structure effectively inhibits the translocation of negatively charged polysulfide ions to enable highly robust Li-S batteries.

In their paper, the researchers show that by using a reduced graphene oxide (rGO)/sodium lignosulfonate (SL) composite on the standard polypropylene (PP) separator (rGO@SL/PP), they demonstrated a highly robust Li-S battery with a capacity retention of 74% over 1,000 cycles.

Researchers at Indian Institute of Technology (IIT) Madras have developed reduced graphene oxide loaded nanocomposite scaffolds for treating normal and diabetic wounds.

Wounds in diabetic patients do not heal as rapidly as it would in a normal and healthy individual, which leads to chronic non-healing wounds that can result in serious complications. Treatment of such chronic non-healing wounds in diabetes is still a major clinical challenge. Although there are some wound dressings that are commercially available, they are very expensive.

Scientists from CSIRCentral Electrochemical Research Institute (CSIR-CECRI) and CSIRCentral Salt and Marine Chemicals Research Institute (CSIR-CSMCRI) in India have collected discarded lithium-ion batteries and created reduced graphene oxide from them. The material reportedly showed high specific capacity at low current, making it an ideal material for next generation high-performance supercapacitors.

The specific capacity was found to be 112 farad per gram from fundamental evaluation, which is almost equal to the commercially available ones. Also the ones available in market today are created using activated carbon which is expensive and environmentally hazardous while our method is cheaper and fully environmental friendly explains the team.

A team led by researchers from the Indian Institute of Technology (IIT) in Bombay, India, has developed a graphene-enhanced inexpensive, flexible pressure sensor that can be used for various health-care applications. The piezoresistive pressure sensor can reportedly monitor even small-scale movements caused by low-pressure variations.

The sensor can measure blood pulse rate in real time when placed on the wrist and neck. The sensor was also tested for its ability to monitor respiration; When placed on the throat, the sensor could detect changes in pressure when different words were pronounced. Interestingly, the fabricated sensor also showed good sensitivity in detecting large-scale motion monitoring, as in the case of bending and extension of finger joints.

Spain based graphene producer Graphenea has launched a new Chinese edition of its web site to specifically target the growing Chinese graphene market. China is becoming a leading adopter of graphene technologies, and Graphenea aims to supply its high-end materials for corporations in China.

Graphenea produces CVD graphene sheets, graphene oxide and reduced graphene oxide materials, which are on sale now in China via its online store.

Scientists at The University of Manchester have reported the development of a simple and cost-effective method to manufacture graphene-based wearable electronic textiles on an industrial scale. The new method could allow graphene e-textiles to be manufactured at commercial production rates of 150 meters per minute, the team said. Our simple and cost-effective way of producing multi-functional graphene textiles could easily be scaled up for many real-life applications, such as sportswear, military gear, and medical clothing, said the researchers.

The team reversed the previous process of coating textiles with graphene-based materials; Traditionally, the textiles are first coated with graphene oxide, which is then converted into its functional form of reduced graphene oxide. Instead, the researchers first reduced the graphene oxide in solution, and then coated the textiles with the reduced form.

Researchers at the University of Wisconsin-Milwaukee will be presenting a graphene-based sensing platform for real-time, low-cost detection of various water contaminants at the AVS's 64th International Symposium & Exhibition, being held Oct. 29-Nov. 3, 2017, in Tampa, Florida. The new sensor detects heavy metals, bacteria, nitrates and phosphates.

The sensor works by placing graphene-based nanosheets that are semiconducting between an electrode gap. The electrical conductivity of the graphene material changes with the binding of substances, called analytes, to its surface and their chemical constituents are identified and measured. "The magnitude of the conductivity change can be correlated to the concentration of analyte, and the technology also involves the functionalization of the graphene material surface with specific probes that can target a specific analyte," said the researchers.

Researchers from South Korea have created a graphene nanoribbon sensor which can measure high vacuum pressures.

The Researchers synthesized a mixture of graphene nanoribbons (of varying size and chemical composition) from a combination of multi-walled carbon nanotubes, sulphuric acid and phosphoric acid in a chemical exfoliation approach. The result was a mixture of several graphene nanoribbons which were separated and purified ready for device implementation and testing. The Researchers also synthesized graphene oxide through a modified Hummers’ method for use as a reference material.