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ZEN Graphene Solutions Partners with Evercloak and NGen for Graphene in Cleantech Manufacturing Project

Posted By Graphene Council, Friday, July 10, 2020
ZEN Graphene Solutions Ltd. (“ZEN” or the “Company”) (TSXV:ZEN) is pleased to announce that Evercloak Inc. (Evercloak) and ZEN have been awarded $125,000 each as part of a Next Generation Manufacturing Canada (NGen) Project.  The project entitled “Advancing Large-Scale Graphene and Thin-Film Membrane Manufacturing” will support the scale up of graphene oxide (GO) production by ZEN to supply GO to Evercloak for their scale up and optimizing activities. NGen supports collaborative technology projects that enable the development of world-leading advanced manufacturing capabilities in Canada.

Francis Dubé, ZEN CEO commented, “ZEN is pleased to support Canadian graphene-based innovations and Evercloak is a wonderful example of what can be achieved with nanomaterials and Canadian entrepreneurship.  NGen supports the accelerated development of high potential technologies such as our graphene collaboration. We look forward to helping Evercloak bring breakthrough technology to everyday life.”

Evelyn Allen, Evercloak CEO stated, “Evercloak is thrilled to be working closely with ZEN to advance graphene-based manufacturing processes in Canada. The NGen Project funding will enable Evercloak to further optimize our membrane manufacturing process, while strengthening collaborations with ZEN, a Canadian graphene technology solutions company.”

“Graphene has long promised to deliver immense benefits across a diverse range of technology applications. This collaborative project between ZEN and Evercloak will fundamentally transform the manufacturing of graphene thin films and will bring forward environmentally friendly solutions in strategic clean technology areas including energy efficiency separation processes, batteries and solar cells to generate sustainable solutions for Canadians.” John Laughlin, CTO, NGen.

Evercloak’s patent-pending HydroAM printer is capable of depositing both 1D and 2D nanomaterials and transferring these ultra-thin films onto flexible substrates with a controlled density for various applications ranging from transparent conductors for flexible electronics to more efficient membranes for industrial separations. Through this grant, and in collaboration with Evercloak, ZEN will optimize and scale-up the electrochemical exfoliation (ECE) process that was developed by Prof. Aicheng Chen and his team at the University of Guelph to produce graphene oxide from its unique precursor Albany PureTM Graphite. The ECE process was designed to be scalable, low cost, low energy, and environmentally friendly to produce high quality, few-layer graphene oxide at ZEN’s Guelph facility.

Tags:  Evelyn Allen  Evercloak  Francis Dube  Graphene  graphene oxide  John Laughlin  membranes  Next Generation Manufacturing Canada  ZEN Graphene Solutions 

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'Unboil an egg' machine creates improved bacteria detector

Posted By Graphene Council, Wednesday, June 24, 2020
The versatility of the Vortex Fluidic Device (VFD), a device that famously unboiled an egg, continues to impress, with the innovative green chemistry device created at Flinders University having more than 100 applications – including the creation of a new non-toxic fluorescent dye that detects bacteria harmful to humans.

Traditional fluorescent dyes to examine bacteria viability are toxic and suffer poor photostability – but using the VFD has enabled the preparation of a new generation of aggregation-induced emission dye (AIE) luminogens using graphene oxide (GO), thanks to collaborative research between Flinders University’s Institute for NanoScale Science and Technology and the Centre for Health Technologies, University of Technology Sydney.

Using the VFD to produce GO/AIE probes with the property of high fluorescence is without precedent – with the new GO/AIE nanoprobe having 1400% brighter high fluorescent performance than AIE luminogen alone (Materials Chemistry Frontiers, "Vortex fluidic enabling and significantly boosting light intensity of graphene oxide with aggregation induced emission luminogen").

“It’s crucial to develop highly sensitive ways of detecting bacteria that pose a potential threat to humans at the early stage, so health sectors and governments can be informed promptly, to act quickly and efficiently,” says Flinders University researcher Professor Youhong Tang.

“Our GO/AIE nanoprobe will significantly enhance long-term tracking of bacteria to effectively control hospital infections, as well as developing new and more efficient antibacterial compounds.”

The VFD is a new type of chemical processing tool, capable of instigating chemical reactivity, enabling the controlled processing of materials such as mesoporous silica, and effective in protein folding under continuous flow, which is important in the pharmaceutical industry. It continues to impress researchers for its adaptability in green chemistry innovations.

“Developing such a deep understanding of bacterial viability is important to revise infection control policies and invent effective antibacterial compounds,” says lead author of the research, Dr Javad Tavakoli, a previous researcher from Professor Youhong Tang’s group, and now working at the University of Technology Sydney.

“The beauty of this research was developing a highly bright fluorescence dye based on graphene oxide, which has been well recognised as an effective fluorescence quenching material.”

The type of AIE luminogen was first developed in 2015 to enable long-term monitoring of bacterial viability, however, increasing its brightness to increase sensitivity and efficiency remained a difficult challenge. Previous attempts to produce AIE luminogen with high brightness proved very time-consuming, requires complex chemistry, and involves catalysts rendering their mass production expensive.

By comparison, the Vortex Fluidic Device allows swift and efficient processing beyond batch production and the potential for cost-effective commercialisation.

Increasing the fluorescent property of GO/AIE depends on the concentration of graphene oxide, the rotation speed of the VFD tube, and the water fraction in the compound – so preparing GO/AIE under the shear stress induced by the VFD’s high-speed rotating tube resulted in much brighter probes with significantly enhanced fluorescent intensities.

Tags:  Flinders University  Graphene  graphene oxide  Healthcare  Youhong Tang 

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High-speed femtosecond laser plasmonic lithography of graphene oxide film

Posted By Graphene Council, Wednesday, May 27, 2020
Graphene analogues, such as graphene oxide (GO) and its reduced forms (rGO), are fascinating carbon materials due to the complementary properties endowed by the sp3-sp2 interconversion, revealing the substitutability and potential for industrialization of integrated graphene devices. Appropriate micro/nanostructural design of GO and rGO for controlling the energy band gap and surface chemical activity is important for developing strategic applications. The femtosecond laser plasmonic lithography (FPL) technology is a qualified candidate for generating the required structures due to its efficiency, high-quality, flexibility and controllability. However, as both the theoretical and experimental explorations of this method are still in their infancy, micro/nanoprocessing of graphene materials using FPL has not been realized. The feasibility of implementing the technique in practical applications is still questionable because most related studies only highlight the characteristics of the structure obtained from the processing but often ignore the complementary changes in the properties of the material itself.

In a new paper published in Light Science & Application, scientists from the State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, China, and co-workers presented a high-quality, efficient and large-area periodic micro/nanoripple manufacturing (~680 nm period) and photoreduction of GO films (~140 nm thickness) on a silicon substrate by using the FPL method. Interestingly, unlike most of the reported laser-induced periodic surface structures (LIPSS) in which the pattern alignment is perpendicular to the polarization of the incident light, they are found to have the extraordinary uniform distribution with orientation parallel to each other in this case. Such a phenomenon cannot be explained by the conventional theory of LIPSS, i.e., the interference between the incident light with TM mode and the excited surface plasmon (SP) wave. The analysis demonstrated that the laser-induced gradient reduction of GO film from its surface to the interior plays a key role, and it leads to an inhomogeneous slab with the maximum dielectric permittivity (DP) at the surface and a smaller DP in the interior that allows excitation of TE-mode surface plasmons (TE-SPs) and the subsequent uncommon interference. Due to the diverse physical mechanisms involved in the laser-rGO interaction, the LIPSS formation also exhibited unique characteristics such as strong robustness against a range of perturbations. Because the microprocessing contains no assistant operations, such as chemical etching, the properties of the graphene material are retained, which allows them for optoelectronic applications. As a matter of fact, through modulation of the photoreduction degree and structural design of the rGO surface, they realized the enhanced light absorption (~ 20%), thermal radiation (> 10°C) and anisotropic conductivities (anisotropy ratio ~ 0.46) from this film material. Based on it, they designed an on-chip, broadband photodetector with stable photoresponsivity (R ~ 0.7 mA W-1) even when exposed to light with the low power (0.1 mW). The authors of the paper summarize the significance of this work as follows:

"(1) The FPL technology is used for the first time to realize the preparation of high-quality, efficient and large-scale periodic micro/nanostructures on the surface of graphene materials; (2) The physical mechanisms of the laser-material interaction involved in FPL technology is further improved; (3) Both the structural characteristics and the properties of the processed material itself are taken into account in the application of photoelectric devices."

"Compared to laser direct writing adopting the same incident laser parameters, our FPL strategy takes only ~1/14000 of the time to process a centimetre-sized sample (1×1.2 cm2). At the same time, due to the possible nonlinear optical property, the FPL strategy induces an obvious 'self-repairing' phenomenon, which can effectively guarantee the processing quality. For example, we can prepare rGO-LIPSS films on different substrates and nondestructively transfer them onto other substrates."

"Our explanation of the experimental phenomena is markedly different from most of the principles at present. This will give us a clearer understanding of the relevant physical processes and lay a solid foundation for the further development of FPL technologies."

"The structured graphene materials by FPL technology present excellent photoelectric performance. The photoresponsivity is numerically comparable to the response of the samples obtained by other reduction methods (e.g., chemical and thermal) and is much larger than that of typical photoreduced ones. The anisotropy ratio is even larger than that of some natural anisotropic crystals. Our work combines the experimental exploration with the in-depth understanding of high-speed micro/nanopatterning of the regular rGO-LIPSS, which not only benefits fundamental physics but also facilitates the practical development of graphene analogues on the industrial scale. "

Tags:  Graphene  graphene oxide  photonics 

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People in Graphene - Revati Kumar Receives Distinguished Faculty Award

Posted By Graphene Council, Tuesday, May 12, 2020

Professor Revati Kumar received the LSU Alumni Association Rising Faculty Research Award for 2020. This award recognizes faculty at the rank of assistant professor who have outstanding records of scholarship and published research. Dr. Kumar is recognized for her value to LSU and contribution to academia. 

“Dr. Kumar is an outstanding scholar who approaches her research, teaching and service duties with dedication and high standards,” wrote LSU Chemistry Chair and Professor John Pojman. “Her participation in department and research activities has been prolific and exemplary.”

Dr. Kumar joined the Department of Chemistry at Louisiana State University in August 2013, with an ongoing joint appointment with LSU’s Center for Computation & Technology (CCT).  A key aspect of her research is the development of computational models to study systems, such as graphene oxide (GO), at relevant length and time scales. Graphene oxide, a model surface system that contains both hydrophobic and hydrophilic domains, adsorbs other molecules and ions and has potential applications in water purification and technologies associated with batteries, fuel cells and catalysts. 

Dr. Kumar and her research group members develop computational molecular dynamics tools to explore the effect of oxygen content on interfacial structural and dynamical heterogeneity.  They simulate the properties and behavior of GOs and their interaction with assorted liquids, including water. Three specific themes that are critical for GO-based technologies are being explored: the competition between hydrophobic and hydrophilic domains on solvation environment and dynamics, reactivity at these interfaces, and structuring at the electrode-electrolyte interface. The development of accurate yet efficient many-body, all atom force-fields as well as molecular interpretations of experimental data are key aspects of this project.

In 2019, Dr. Kumar was named an awardee of the NSF CAREER Program through the Chemical Structure, Dynamics, and Mechanisms-A (CSDM-A) program of the Chemistry Division. The five-year award acknowledges her national standing and potential as a scientific leader. Her research project will enable the design of GO materials with tailored properties for potential applications. A key publication for this NSF project, titled “Interfacial Water at Graphene Oxide Surface:  Ordered or Disordered?” was featured in a Special Young Investigators Edition of the Journal of Physical Chemistry B, an American Chemical Society (ACS) journal.  

Dr. Kumar is also a co-principal investigator (co-PI) with Professor Chris Arges (PI) in Engineering on a Department of Energy (DOE) grant which targets understanding and modeling counterion condensation in polyelectrolytes to develop better separation technologies. She is co-investigating the role of molecular environments on the charge transport behavior of electrolytes for next generation rechargeable battery technologies.

Since her start as an independent researcher at LSU, Dr. Kumar has established an outstanding publication record with a total 25 papers. Most her work at LSU has appeared in high-impact journals (e.g., ACS Journal of Physical Chemistry, the Journal of the American Chemical Society, Langmuir, Physical Chemistry Chemical Physics, and Angewandte Chemie, International Edition).

Her increased visibility for her work at the national level has resulted in 31 invited talks at Universities and at National Conferences, including the Greater Boston Area Theoretical Seminar Series hosted jointly by Harvard, MIT and Boston University, ChemDice Telluride workshops, DOE workshops, and ACS national meetings. Dr. Kumar also received the 2019 OpenEye award for research excellence for Junior Faculty from the ACS Computers in Chemistry Division.

“Dr. Kumar has built a nationally competitive independent research program at LSU,” shared Dr. Jayne Garno, Professor of Chemistry and chair of Dr. Kumar’s mentoring committee. “Her future research will continue to build on the infrastructure she has established while seeking to expand the scope of her research portfolio.”  

Tags:  Chris Arges  Graphene  Graphene Oxide  Jayne Garno  Louisiana State University  Revati Kumar 

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Supercapacitor promises storage, high power and fast charging

Posted By Graphene Council, Wednesday, May 6, 2020
A new supercapacitor based on manganese oxide could combine the storage capacity of batteries with the high power and fast charging of other supercapacitors, according to researchers at Penn State and two universities in China.

“Manganese oxide is definitely a promising material,” said Huanyu "Larry" Cheng, assistant professor of engineering science and mechanics and faculty member in the Materials Research Institute, Penn State. “By combining with cobalt manganese oxide, it forms a heterostructure in which we are able to tune the interfacial properties.”

The group started with simulations to see how manganese oxide’s properties change when coupled with other materials. When they coupled it to a semiconductor, they found it made a conductive interface with a low resistance to electron and ion transport. This will be important because otherwise the material would be slow to charge.

“Exploring manganese oxide with cobalt manganese oxide as a positive electrode and a form of graphene oxide as a negative electrode yields an asymmetric supercapacitor with high energy density, remarkable power density and excellent cycling stability,” according to Cheng Zhang, who was a visiting scholar in Cheng’s group and is the lead author on a paper published recently in Electrochimica Acta.

The group has compared their supercapacitor to others and theirs has much higher energy density and power. They believe that by scaling up the lateral dimensions and thickness, their material has the potential to be used in electric vehicles. So far, they have not tried to scale it up. Instead, their next step will be to tune the interface where the semiconducting and conducting layers meet for even better performance. They want to add the supercapacitor to already developed flexible, wearable electronics and sensors as an energy supply for those devices or directly as self-powered sensors.

Cheng Zhang is now an assistant professor at Minjiang University, China. The second Chinese university is Guizhou Education University. The paper is “Efficient Coupling of Semiconductors into Metallic MnO2@CoMn2O4 Heterostructured Electrode with Boosted Charge Transfer for High-performance Supercapacitors.”

Tags:  Cheng Zhang  Graphene  graphene oxide  Huanyu Larry Cheng  Minjiang University  Penn State  Supercapacitor 

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Instantaneous reduction of graphene oxide using electric spark for wearable sensors

Posted By Graphene Council, Monday, May 4, 2020
Wearable electronic devices, worn on clothes or the skin to record body parameters such as heartbeat and pulse rate, are currently in great demand. 2D nanomaterials such as graphene, with their exceptional electrical and mechanical properties, play a key role in fabricating these devices. Graphene oxide (GO) is a scalable and low-cost alternative to pristine graphene. However, GO is an insulator and needs to be reduced to an electrically conducting form called reduced Graphene Oxide (rGO) to make it useful for sensors. 

A group of IISc researchers has now devised a novel method to instantaneously reduce graphene oxide using an electric spark.

This method, outlined in a paper published in ACS Applied Materials and Interfaces, is efficient and cost-effective, which would allow easy industrial scale-up. It is also more environment-friendly compared to existing methods as it does not generate chemical residues. Sensors developed using this method can have applications in gesture control, in biomedical rehabilitation to detect the degree and intensity of body movements, and in the field of robotics. 

Graphene and its derivatives are versatile in their electrical and structural properties, and are therefore the preferred materials used to build flexible sensors. The chemical structure of GO allows it to form ‘printable inks’ with various solvents, and bind to the substrate better. Various reduction techniques, including thermal, UV, laser, and microwave-based methods, are used to modify the chemical structure and form rGO. However, these methods are expensive and time-consuming, often produce toxic by-products, and can also damage the substrate.

To reduce graphene oxide efficiently and quickly, the IISc team used an electrical discharge under ambient conditions, popularly known as an electric spark. Sparking on GO deposited over a porous substrate enables its instantaneous reduction, along with a large drop in electrical resistance.

By varying certain parameters in the spark stream, the team was able to tweak the degree of reduction of graphene oxide, and also make predefined conducting patterns, which offers more flexibility in sensor fabrication. The heat present in the spark is highly localised and does not cause any substrate damage; this was verified using a Scanning Electron Microscope.

When mechanical stress is applied to the rGO-coated fabric, it causes a proportional change in the electrical resistance of the rGO film. This property is essential for it to function efficiently as a flex sensor. The change in electrical resistance was found to be consistent over repeated tests and under different bending angles, says Rajanna Konandur, Honorary Professor at the Department of Instrumentation and Applied Physics, and corresponding author of the paper.

He and his team integrated flex sensors containing these spark-reduced rGO films on commercially available gloves, and tested them using bending and other finger movements. Further research can pave the way for inexpensive, large-scale production of flexible, wearable electronics that use these films.

Tags:  2D materials  Graphene  Graphene Oxide  Indian Institute of Science Bengaluru  Medical  nanomaterials  Rajanna Konandur  Sensors 

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First Graphene March Quarterly Activities Review

Posted By Graphene Council, Saturday, May 2, 2020
On the 18 March, the Company advised shareholders that the University of Manchester had closed all its non-essential research laboratories, including the GEIC, from 5:00pm, Tuesday 17th March. Our staff ensured all experiments were shut down safely, chemicals and raw materials were safely stored, and all confidential papers locked away.

Experimental work in the UK is on hold and our staff have provided scientific support to colleagues in Australia and customers globally, while consolidating our foundations in regulatory approval, manufacturing strategy, intellectual property and new market development. The UK team is well prepared to pick up operations and has identified the steps for immediate return to work once restrictions are lifted.

First Graphene’s key priorities on COVID-19 continue to be for the Company to play its role in limiting the spread of the virus, protecting the health and safety of its employees, delivering value for its customers and stakeholders. We are pleased to report that we have no COVID-19 related illnesses within our workforce.

We are also ensuring the Company is implementing appropriate strategies and actions to place First Graphene in the strongest possible financial position in this ever-changing environment.

In addition to its focus on the health and wellbeing of the workforce the Company implemented strategies to ensure it is in the strongest possible financial position. These strategies continue to be focused on liquidity management and include deferment of non- essential capital and cost reductions while maintaining the continuity of its production and research operations.

Entitlement Issue to Strengthen Balance Sheet
Since the close of the March quarter, the Company has announced that it is undertaking a 1 for 10 Entitlement issue to all shareholders, at a subscription price of 13¢. There will be a 1 for 1 free attaching option for each share taken up, being the same options series currently trading on the ASX (FGROC).

The Company has previously raised equity capital via placements to sophisticated investors who qualify under the s708 Corporations Law exceptions. However, while the Company still has a solid cash position, the directors have elected in this instance, to undertake an entitlement issue despite the share price having been adversely affected by the coronavirus concerns. Directors see this as the best way to make shares available at modest prices to all shareholders equally. Meanwhile, ensuring that the Company is well-funded for the continued and exciting growth curve that has only just begun. A growing business needs higher levels of working capital.
Steel Blue Supply Agreement.

It was announced on 21 January, that Steel Blue had signed a two-year supply agreement whereby it would exclusively source PureGRAPH® for the sole in a new line of work safety boots. Steel Blue will also be looking to include PureGRAPH® into the Met-Guard and other areas of the boot in the future.
 
This Supply Agreement followed on from First Graphene being able to successfully incorporate PureGRAPH® into a thermoplastic polyurethane (“TPU”). While existing TPU’s already possess high abrasion resistance and tensile strength, the incorporation of PureGRAPH® has improved mechanical properties whilst providing additional benefits in thermal heat transfer, chemical resistance and reduced permeability. Continued positive results from mining industry field trials.

As advised on 3 February, the newGen-provided Armour-GRAPH™ bucket liner supplied to a major iron ore producer containing PureGRAPH®20 continued being trialled. The bucket liner showed no signs of advanced wear or scalloping as would normally be experienced with the liners currently used in industry after 24 weeks of use. The client has continued the trial, with a further inspection to be undertaken in another 12 weeks from that date.

The same client also installed a second ArmourGRAPH™ bucket liner at the same Pilbara mine site. With this liner performing well we are now seeing ArmourGRAPH™ liners being installed for trials with other newGen iron ore producing clients.

The buckets were inspected in late April and the PureGRAPH® enhanced bucket liners remained in good operational condition. The client intends to push toward their targeted wear life of twelve months. The next inspection will be in July, at which point the liners will be replaced and returned for post operational inspection. This further demonstrates the dramatically increased wear resistance the PureGRAPH® range of products can provide to sacrificial wear applications.

Developing Advanced Graphene Materials for Next Generation Supercapacitors
In September 2019, the Company announced the signing of a worldwide, exclusive licence agreement with the University of Manchester for the manufacture of hybrid- graphene materials by electrochemical processing. Two high value product groups can be synthesised using this approach.

• Firstly, metal oxide decorated materials with high capacitance for super capacitor and electrocatalyst applications; and
• Secondly, pristine graphene products with tightly controlled oxygen levels for applications in electrical and thermal conductivity.

The manufacturing process employed builds on the Company’s existing electrochemical processing expertise which is scaled to 100 tonne per year capacity at FGR’s manufacturing site at Henderson, WA.

The licence agreement was quickly followed in October 2019 by the initiation of a UK government funded EPSRC (Engineering and Physical Sciences Council) project to transfer the technology from the University laboratories to First Graphene laboratories.

Since October, the Company has successfully transferred the technology to its laboratories in Manchester, UK and has also completed two successful pilot trials at its manufacturing facility in Henderson, WA. Specifically, the Company was able to demonstrate the following:
• Synthesis of metal oxide decorated hybrid graphenes at litre scale in FGR laboratories;
• Synthesis of pristine (zero-oxygen) graphene materials at litre scale in FGR laboratories;
• Manufacture of metal oxide decorated hybrid graphenes at multi-kilogram scale; and
• Manufacture of pristine (zero-oxygen) graphene materials at multi-kilogram scale.

The structure of the new materials has been confirmed by Raman analysis and Scanning Electron Microscopy (SEM). A typical image of metal oxide decorated graphene is shown in Fig. 1 which shows the nanostructured metal oxides on the surface of an exfoliated graphene platelet.

The FGR team is testing the performance of these materials in energy storage and catalysis applications. Initial testing has shown the prototype supercapacitor devices (coin cell) can be manufactured with these materials. Additional testing is presently delayed due to restricted access to test facilities as a consequence of COVID-19 actions.

In parallel to the experimental programme, the Company has actively sought end- users for novel supercapacitor products. The need for supercapacitors with higher performance from those currently available have been validated by end-users in the aerospace, marine, electric vehicle and utility storage sectors. The Company is also seeking government funding to develop a new supply chain for game changing supercapacitor devices and have received letters of support from several key industry players.

Continued Growth in Customer Engagement
Despite the circumstances resulting from COVID-19, the Company continued to receive well-qualified enquiries in Australia during March. A number of these were from the mining services sector, which continues to be an area of focus for the Company, where PureGRAPH® has proven its ability to improve mechanical performance in a range of polyurethane based products.

The shutdown in Europe has slowed down customer evaluation trials across the region. However, we can report that a major European based multinational placed a 4th order for kilogram development quantities of PureGRAPH® products for inclusion in an early phase commercialisation programme.

Strong Advances in VFD Development Background Summary on Graphene Oxide
Graphene oxide (GO) is the chemically modified derivative of graphene, whereby the basal planes and edges have been functionalised with oxygen containing functional groups such as hydroxyl, epoxy and carboxyl groups. These oxygen functionalities make GO hydrophilic and therefore dispersible, forming homogenous colloidal suspensions in water and most organic solvents. This makes it ideal for use in a range of applications.

To date, the most widely used process for the synthesis of graphene oxide is the Hummer’s method. This typically requires strong acids and oxidants, such as potassium chlorate (KClO3), nitric acid (HNO3), concentrated sulphuric acid (H2SO4) and potassium permanganate (KMnO4). Much work has been done by other parties to improve the synthesis methods while maintaining high surface oxidation, but these continue to rely on the use of strong acids and oxidants.

Through its subsidiary 2D Fluidics Pty Ltd, FGR has made considerable progress in developing a more benign processing route for oxidised graphene. The objective is to provide controlled levels of surface oxygen functionality to give better compatibility in aqueous and organic systems. This will not incur the higher oxygen (and other defect) levels which result from Hummer’s method and its subsequent reduction steps. It will also provide the ability to “tune or optimise” the surface oxidation level to suit respective applications.

FGR’s method synthesises GO directly from bulk graphite using aqueous H2O2 as the green oxidant. Different energy sources have been used for the conversion of H2O2 molecules into more active peroxidic species, such as a combination of a pulsed Nd:YAG laser and/or other light sources. The irradiation promotes the dissociation of H2O2 into hydroxyl radicals which then leads to surface oxidation.

The technology has been successfully transferred to the FGR laboratories at the Graphene Engineering and Innovation Centre (GEIC) in Manchester where it has undergone further development and optimisation to identify, understand and resolve future upscaling issues.

XPS analysis showed the use of a pre-treatment step in combination with the near infrared laser gave oxidised graphene sheets with an average surface oxidation of ~30-35%: this will enhance compatibility with aqueous systems.

Further trials have already demonstrated the two-step process is reproducible and versatile, with the ability to process different starting materials of graphite. The multi- disciplinary team has identified the control of the feed rate and energy input will allow us to control the surface oxidation, providing a consistent material that can be tailored as required for a range of applications.

Figure 5 shows that increase in surface oxygen content for two starting materials: graphite ore (top) and PureGRAPH® graphene (bottom). As we go through the two- stage process, in both cases the surface oxygen functionality increases. The end- product has a range of functional groups, including C-O, C=O and COOH.

Launch of Advertising Campaign Directed at Mining Companies
With the success being achieved in mining wear products, the Company is launching an advertising campaign directed at Australia’s mining companies. The campaign will be run on social media platforms and in mining publications. A copy of the proposed advertisement is attached to this Quarterly Activities Review.

Tags:  2D Fluidics Pty Ltd  First Graphene  Graphene  graphene oxide  newGen  Steel Blue  Supercapacitors 

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ZEN Graphene Solutions Announces Collaboration with Graphene Composites Ltd. to Develop a COVID-19 Virucidal Graphene-Based Composite Ink for Face Masks

Posted By Graphene Council, Thursday, April 30, 2020
ZEN Graphene Solutions Ltd. is pleased to announce an international collaboration with UK-based Graphene Composites Ltd (GC) to fight COVID-19 by developing a potential virucidal graphene-based composite ink that can be applied to fabrics including N95 face masks and other personal protective equipment (PPE) for significantly increased protection. Once the development, testing, and confirmation of the graphene ink’s virucidal ability have been completed, the ink will then be incorporated into fabrics used for PPE.

Francis Dubé, CEO of ZEN commented, “We are pleased to be collaborating with GC and be on the forefront of a new innovative technology that could contribute to combating the deadly COVID-19 virus. The development of this potential COVID-19 virucidal graphene ink is coming at a crucial time to provide effective PPE supplies for the safety of frontline workers and hospital staff.” Dr. Dubé continued, “The current N95 masks trap the virus but don’t kill it. Our testing will demonstrate if the graphene ink is an effective virucide which would kill the virus as this could make a big difference to people’s safety. We have been very impressed by the Graphene Composites team and look forward to continued collaborations.”

Sandy Chen, CEO of GC stated, “Combining the deep nanomaterials expertise of GC and ZEN with a truly collaborative approach has enabled us to do a year’s worth of R&D in a matter of weeks. Quickly developing and deploying our virucidal/germicidal ink would make a significant difference in slowing the rate of infection – thus saving many lives.”

Under the collaboration, ZEN has synthesized a silver nanoparticles functionalized graphene oxide ink at their lab in Guelph, Ontario that has been documented by previous researchers to kill earlier versions of coronavirus. Once testing is completed, the ZEN/GC graphene ink would then be incorporated into a fabric to be included into masks and filters designed by GC.

Efficacy testing of the silver-graphene oxide-based ink to kill the COVID 19 virus (SARS-CoV-2) will be conducted at Western University’s ImPaKT Facility Biosafety Level 3 lab in Ontario. In addition, the graphene ink will be tested to kill influenza A and B viruses at Biosafety Level 2 labs in the UK and US.

Tags:  Francis Dubé  Graphene  Graphene Composites  graphene oxide  nanomaterials  Sandy Chen  ZEN Graphene Solutions 

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DST INSPIRE Faculty develops nanomaterials having energy storage application & optical sensors for water pollution control

Posted By Graphene Council, Saturday, April 25, 2020
A recipient of the INSPIRE Faculty Award instituted by the Department of Science & Technology (DST), Govt. of India. Dr. Ashish Kumar Mishra, Assistant Professor at the Indian Institute of Technology (BHU), Varanasi, has made significant achievements in developing nanomaterials based supercapacitors to achieve high energy density and power density of supercapacitors, along with his group.

Increasing energy demand due to the growth of human population and technological advancement poses a great challenge for human society. High energy density of supercapacitors suggests that constant current can be withdrawn for longer duration without recharging. Hence automobiles can run longer distances without charging. Supercapacitors can be an alternative for such purposes.

Dr. Mishra and his research group at IIT (BHU) have developed a reduced graphene oxide (rGO) at a moderate temperature of 100°C with high capacitance performance. The production process is a cost-effective one, making it suitable for commercial purposes. This work has been published in Materials Research Express.

The group which works on carbon (Carbon Nanotubes, Graphene) and metal dichalcogenides (MoS2, MoSe2, etc.) nanomaterials based supercapacitors to achieve high energy density and power density of supercapacitors, have also developed a novel green approach for synthesis of Iron-based nanocatalyst, which can be used for large scale production of Cabon Nanotubes.

In addition to energy storage, Dr. Mishra’s group is also working on optoelectronic applications of nanomaterials. In this context, they are working on developing novel nanostructures of carbon and metal dichalcogenides semiconductors for photodetection and surface-enhanced Raman spectroscopy (SERS). Through this work, they have demonstrated excellent photodetection behaviour of different architectures of nanoscale MoS2 for the detection of visible light. The high photoresponsivity obtained in this work can be useful to develop ultrafast detectors for signalling purpose. The work has been published in the Journal of Physical Chemistry Letters.

The SERS can help detect harmful molecules present in water at ultra-low concentrations. His group has successfully demonstrated detection of Rhodamine 6G (R6G), an organic laser dye up to lowest limit of sub-nano-molar concentration using rGO and MoS2 nanomaterials. This work has been published in the Journal of Physical Chemistry C. They have also examined the nonlinear optical response of the material developed, which suggests that some of these materials can be used to develop protectors for high power light sources like lasers.

Their focus on energy and optoelectronics devices paves the way for the development of cost-effective and efficient devices, which can be used for energy storage application. Their findings make way for materials which can be used as advanced photodetectors and also be used as optical sensors for water pollution control.

Tags:  Ashish Kumar Mishra  Cabon Nanotubes  Energy  energy storage  Graphene  graphene oxide  Indian Institute of Technology (BHU)  nanomaterials  supercapacitors 

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3D printed tissue-like vascular structures investigated on Larmor

Posted By Graphene Council, Friday, April 24, 2020
An international team of scientists have discovered a new material that can be 3D printed to create tissue-like vascular structures.

Material platforms that exploit the functionalities of both proteins and graphene oxide offer exciting possibilities for the engineering of advanced materials. This study introduces a method to 3D print graphene oxide with a protein that can organise into tubular structures that replicate some properties of vascular tissue.

Self-assembly is the process by which multiple components can organise into larger well-defined structures. Biological systems rely on this process to controllably assemble molecular building-blocks into complex and functional materials exhibiting remarkable properties such as the capacity to grow, replicate, and perform robust functions.

Including graphene as a building-block could lead to the design of new biomaterials that benefit from its distinctive electronic, thermal, and mechanical properties. Graphene oxide is also gaining significant interest as a starting material; being used instead of graphene because its rich oxygen-containing functional groups can facilitate specific interactions with different molecules.

In this study, published in Nature Communications, a new biomaterial is made by the self-assembly of a protein with graphene oxide. The mechanism of assembly enables the flexible (disordered) regions of the protein to order and conform to the graphene oxide, generating a strong interaction between them. By controlling the way in which the two components are mixed, it is possible to guide their assembly at multiple size scales in the presence of cells and into complex robust structures.

"This work offers opportunities in biofabrication by enabling simultaneous top-down 3D bioprinting and bottom-up self-assembly of synthetic and biological components in an orderly manner from the nanoscale," explains researcher Professor Alvaro Mata; “Here, we are biofabricating micro-scale capillary-like fluidic structures that are compatible with cells, exhibit physiologically relevant properties, and have the capacity to withstand flow. This could enable the recreation of vasculature in the lab and have implications in the development of safer and more efficient drugs, meaning treatments could potentially reach patients much more quickly."

By using Small Angle Neutron Scattering (SANS) on Larmor alongside simulations and other experimental techniques, the group was able to describe the key steps of the underlying molecular mechanism. In particular, SANS facilitated the understanding of the unique protein-graphene oxide organization and establishment of the rules for turning these interactions into a supramolecular fabrication process.

The system they produced showed remarkable stability, robust assembly, biocompatibility, and bioactivity. These properties enable its integration with rapid-prototyping techniques to bio-fabricate functional microfluidic devices by directed self-assembly, opening new opportunities for engineering more complex and biologically relevant tissue engineered scaffolds, microfluidic systems, or organ-on-a-chip devices.

Tags:  3D Printing  Alvaro Mata  Biomaterials  Graphene  graphene oxide  Healthcare 

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