Membranes - Page 3

Researchers from Australia's Monash University and CSIRO Manufacturing have designed a permselective membrane based on reduced graphene oxide (rGO) for making practical lithium-sulfur batteries. 

The membrane closely mimics a cell plasma membrane, demonstrating selective Li+ transport and the ability to not only retain polysulfides, but also 're-activate' them on the membrane's electrochemically active interface. The team used the membrane to demonstrate high loading and high rate Li-S batteries, also on a pouch cell level.

Researchers from Lawrence Berkeley National Laboratory and University of California at Berkeley recently used graphene to develop an imaging platform that enabled nondestructive spectroscopic imaging of soft materials with nanometer spatial resolution, under in vitro conditions and external stimuli. Using the Advanced Light Source (ALS) particle accelerator as an infrared light source, the researchers performed the nanometer-scale spatial resolution imaging of proteins in the proteins’ natural liquid environment. They observed how the self-assembly of the proteins was affected by environmental conditions in the surrounding liquid.

Current imaging tools often use ionizing radiation under conditions that are far from the molecule’s native biological environment. Powerful imaging techniques such as fluorescence microscopy can potentially damage biological material, and they often do not provide chemical information. To resolve this challenge, the researchers combined nano-Fourier transform infrared (nano-FTIR) spectroscopy with graphene-capped liquid cells. The imaging platform could open opportunities in the study of soft materials for sectors that range from biology to plastics processing to energy.

Scientists from Vanderbilt University recently developed a lightweight and ultra-compact graphene-based filter that can block aerosolized nanoparticles of size in the sub-20 nm range. 

Nanoparticulate aerosols contain toxins, pollutants, and harmful viruses, whose size varies between 20 and 300 nm in diameter. Although conventional air filters, such as 95% efficiency filter (N95) and the high-efficiency particulate air filter (HEPA), exhibit superior air flow rates, they are unable to inhibit nanoparticulate aerosols whose size is less than 300 nm. Facemasks that can block nanoparticulate aerosols of size below 300 nm are bulky and develop thermal stress due to low breathability. To improve the applicability of PPEs, several strategies are implemented that focus on making porous polymers, with greater thickness, which can filter out nanoparticulate aerosol toxins, pathogens, and pollutants.

Researchers from University College London have demonstrated a graphene nanomesh membrane that possesses high hydrophilicity, super-oleophobicity and low oil adhesion underwater.

The researchers in this work have put a nature-inspired spin on the fabrication of high-performance graphene membranes for tricky oil/water separations even in stable emulsions. They demonstrated graphene nanomesh membranes within a wide pH range at impressive water permeance (close to 4000 L m2 h1 bar1) under a very low trans-membrane pressure difference.

Watercycle Technologies, a spin-out company from The University of Manchester, has secured initial funding for its technology that uses graphene-based membranes and systems to extract lithium and other minerals from brines and water solutions.

Led by Sebastian Leaper, a former PhD student from the Department of Materials at Manchester, Watercycle Technologies has taken Tier 2 membership of the Graphene Engineering Innovation Centre (GEIC), with lab space and access to advanced 2D materials facilities and expertise in prototyping.

Researchers at the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences (CAS), in collaboration with teams from China's Lanzhou University and Hebei University, have developed a graphene oxide-based method of pre-enriching uranium in seawater by membrane filtration.

In their study, the scientists fabricated a new type of glycine cross-linked composite graphene oxide (GO-Gly) membrane with good ion sieving properties, which can meet the demands of uranium pre-enrichment in seawater.

A team of researchers from TU Delft, led by dr. Farbod Alijani, recently managed to capture the low-level noise of a single bacterium using graphene.

Being able to pick up on the miniscule sounds of bacteria can help track if an antibiotics is working, or if the bacteria are resistant to the antibiotic. Alijani's team was originally looking into the fundamentals of the mechanics of graphene, but at a certain point they wondered what would happen if it comes into contact with a single biological object.

NematiQ, an Australia-based developer of graphene oxide (GO) membranes for water treatment applications, has reported commercial-scale manufacture of an innovative graphene membrane.

Over the last five years, NematiQ has developed a patented, layer-by-layer methodology to produce the graphene membrane. NematiQ has achieved a milestone by producing more than 1,000 meters worth of 1,000-millimetre-wide flat sheet graphene membrane, at speed, on an industrial roll-to-roll coating machine, showcasing its ability to manufacture graphene membrane at a commercial scale.

A team of researchers, led by Professor Sir Andre Geim at The University of Manchester, in collaboration with scientists from Belgium and China, used low-energy electrons to make individual atomic-scale holes in suspended graphene. The holes came in sizes down to about two angstroms, smaller than even the smallest atoms like helium and hydrogen.

The researchers report that they achieved practically perfect selectivity (better than 99.9%) for such gases as helium or hydrogen with respect to nitrogen, methane or xenon. Also, air molecules (oxygen and nitrogen) pass through the pores easily relative to carbon dioxide, which is >95% captured.

Directa Plus has stated that its graphene technology is being used in a newly-launched high-tech range of trail shoes.

Directa Plus said a specially developed graphene membrane is integrated into the lining of the norda 001 G+ Spike high-performance trail shoes, which are now available for consumer purchase.