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Scientists create ultraviolet light on a graphene surface

Posted By Graphene Council, The Graphene Council, Sunday, June 2, 2019
Updated: Friday, May 31, 2019

Ultraviolet light is used to kill bacteria and viruses, but UV lamps contain toxic mercury. A newly developed nanomaterial is changing that.

The nano research team led by professors Helge Weman and Bjørn-Ove Fimland at the Norwegian University of Science and Technology (NTNU)’s Department of Electronic Systems has succeeded in creating light-emitting diodes, or LEDs, from a nanomaterial that emits ultraviolet light (Nano Letters, "GaN/AlGaN Nanocolumn Ultraviolet Light-Emitting Diode Using Double-Layer Graphene as Substrate and Transparent Electrode").It is the first time anyone has created ultraviolet light on a graphene surface.

“We’ve shown that it’s possible, which is really exciting,” says PhD candidate Ida Marie Høiaas, who has been working on the project with Andreas Liudi Mulyo, who is also a PhD candidate.
“We’ve created a new electronic component that has the potential to become a commercial product. It’s non-toxic and could turn out to be cheaper, and more stable and durable than today’s fluorescent lamps. If we succeed in making the diodes efficient and much cheaper, it’s easy to imagine this equipment becoming commonplace in people’s homes. That would increase the market potential considerably,” Høiaas says.

Dangerous – but useful

Although it’s important to protect ourselves from too much exposure to the sun’s UV radiation, ultraviolet light also has very useful properties. This applies especially to UV light with short wavelengths of 100-280 nanometres, called UVC light, which is especially useful for its ability to destroy bacteria and viruses. Fortunately, the dangerous UVC rays from the sun are trapped by the ozone layer and oxygen and don’t reach the Earth. But it is possible to create UVC light, which can be used to clean surfaces and hospital equipment, or to purify water and air.

The problem today is that many UVC lamps contain mercury. The UN’s Minamata Convention, which went into effect in 2017, sets out measures to phase out mercury mining and reduce mercury use. The convention was named for a Japanese fishing village where the population was poisoned by mercury emissions from a factory in the 1950s.

Building on graphene

A layer of graphene placed on glass forms the substrate for the researchers’ new diode that generates UV light.

Graphene is a super-strong and ultra-thin crystalline material consisting of a single layer of carbon atoms. Researchers have succeeded in growing nanowires of aluminium gallium nitride (AlGaN) on the graphene lattice.

The process takes place in a high temperature vacuum chamber where aluminium and gallium atoms are deposited or grown directly on the graphene substrate – with high precision and in the presence of nitrogen plasma. This process is known as molecular beam epitaxy (MBE) and is conducted in Japan, where the NTNU research team collaborates with Professor Katsumi Kishino at Sophia University in Tokyo.

Let there be light

After growing the sample, it is transported to the NTNU NanoLab where the researchers make metal contacts of gold and nickel on the graphene and nanowires. When power is sent from the graphene and through the nanowires, they emit UV light. Graphene is transparent to light of all wavelengths, and the light emitted from the nanowires shines through the graphene and glass.

“It’s exciting to be able to combine nanomaterials this way and create functioning LEDs, says Høiaas.
An analysis has calculated that the market for UVC products will increase by NOK 6 billion, or roughly US $700 million between now and 2023. The growing demand for such products and the phase- out of mercury are expected to yield an annual market increase of almost 40 per cent.

Concurrently with her PhD research at NTNU, Høiaas is working with the same technology on an industrial platform for CrayoNano. The company is a spinoff of NTNU’s nano research environment.

Use less electricity more cheaply

UVC LEDs that can replace fluorescent bulbs are already on the market, but CrayoNano’s goal is to create far more energy-efficient and cheaper diodes. According to the company, one reason that today’s UV LEDs are expensive is that the substrate is made of costly aluminium nitride. Graphene is cheaper to manufacture and requires less material for the LED diode.
Høiaas believes that the technology needs to be improved quite a bit before the process developed at NTNU can be scaled up to industrial production level.

Among the issues that need to be addressed are conductivity and energy efficiency, more advanced nanowire structures and shorter wavelengths to create UVC light. CrayoNano has made progress, but results documenting their progress have not yet been published. “CrayoNano’s goal is to commercialize the technology sometime in 2022,” says Høiaas.

Tags:  Bjørn-Ove Fimland  CrayoNano AS  Graphene  Helge Weman  nanomaterials  Norwegian University of Science and Technology  ultraviolet 

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Flexible, transparent monolayer graphene device for power generation and storage

Posted By Graphene Council, The Graphene Council, Wednesday, May 15, 2019
Updated: Tuesday, May 14, 2019
Researchers at Daegu Gyeongbuk Institute of Science and Technology developed single-layer graphene based multifunctional transparent devices that are expected to be used as electronics and skin-attachable devices with power generation and self-charging capability (ACS Applied Materials & Interfaces, "Single-Layer Graphene-Based Transparent and Flexible Multifunctional Electronics for Self-Charging Power and Touch-Sensing Systems").

Senior Researcher Changsoon Choi's team actively used single-layered graphene film as electrodes in order to develop transparent devices. Due to its excellent electrical conductivity and light and thin characteristics, single-layered graphene film is perfect for electronics that require batteries.

By using high-molecule nano-mat that contains semisolid electrolyte, the research team succeeded in increasing transparency (maximum of 77.4%) to see landscape and letters clearly.

Furthermore, the research team designed structure for electronic devices to be self-charging and storing by inserting energy storage panel inside the upper layer of power devices and energy conversion panel inside the lower panel. They even succeeded in manufacturing electronics with touch-sensing systems by adding a touch sensor right below the energy storage panel of the upper layer.

Senior Researcher Changsoon Choi in the Smart Textile Research Group, the co-author of this paper, said that "We decided to start this research because we were amazed by transparent smartphones appearing in movies. While there are still long ways to go for commercialization due to high production costs, we will do our best to advance this technology further as we made this success in the transparent energy storage field that has not had any visible research performances."

Tags:  Batteries  Changsoon Choi  Daegu Gyeongbuk Institute of Science and Technolog  Graphene  nanomaterials 

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New graphene-based material developed for medical implants

Posted By Graphene Council, The Graphene Council, Thursday, May 2, 2019
Updated: Wednesday, May 1, 2019
A group of scientists have developed a new material for biomedical applications by combining a graphene-based nanomaterial with Hydroxyapatite (HAp), a commonly used bioceramic in implants.

In recent years, biometallic implants have become popular as a means to repair, restructure or replace damaged or diseased parts in orthopaedic and dental procedures. Metal parts also find use in devices such as pacemakers.

However, metallic implants face several limitations and are not a permanent solution. They react with body fluids and corrode, release wear and tear debris resulting in toxins and inflammation. They also have high thermal expansion and low compressive strength causing pain and are dense and may cause reactions.

On the other hand, bioceramics do not have these limitations. HAp specifically is osteoconductive, with a bone-like porous structure offering the required scaffold for tissue re-growth. However, it is brittle and lacks the mechanical strength of metals. The problem is overcome by combining it with nanoparticles of materials such as Zirconia.

In the new research, scientists have combined HAp with graphene nanoplatelets. “Previously reported studies have focused on only structural properties of such composites without throwing light on their biological properties. We have found that combining HAp with graphene nanomaterial enhances mechanical strength, provides better in-vivo imaging and biocompatibility without changing its basic bone-like properties,” explained Dr Gautam Chandkiram, the principal investigator at University of Lucknow, while speaking to India Science Wire.

Purification of the base ceramic material is a significant primary challenge in fabricating composites. According to scientists, in the current study, highly efficient biocompatible Hydroxyapatite was successfully prepared via a microwave irradiation technique and the consequent composites was synthesised using a simple solid-state reaction method.

The process involved mixing different concentrations of graphene nanoplatelet powders and drying, crushing, sieving and ball-milling the resulting slurry. The fine composite powder was further cold-compressed and sintered at 1200 degrees Celsius to achieve the desired density.

The scientists found that the composite had adequate interfacial area between the nanoparticles, with the graphene nanoplatelets well distributed into the hydroxyapatite matrix, while exhibiting high fracture resistance. Further, structural characterization, mechanical and load bearing tests showed that the 2D nature of graphene improves the load transfer efficiency significantly.

Researchers also examined cell viability of the composite by observing metabolic activity in specific cells using a procedure known as MTT assay. They used gut tissues of Drosophila larvae and primary osteoblast cells of a rat. “The overall cell viability studies demonstrated that there is no cytotoxic effect of the composites on any cell type,” explained Dr. Gautam.

Biomaterials also find use in drug delivery and bioimaging diagnosis. “Our research on the composite found that it displays a better fluorescence behaviour as compared to pure hydroxyapatite, indicating it has a great potential in bone engineering and bioimaging bio-imaging applications as well,” he added.

Tags:  2D Materials  Gautam Chandkiram  Graphene  Medical  nanomaterials  University of Lucknow 

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Thomas Swan Advanced Materials announce exciting Graphene collaboration with Graphene Composites Ltd pioneering advanced protection against knife and gun-crime

Posted By Graphene Council, The Graphene Council, Wednesday, May 1, 2019
Thomas Swan is proud to collaborate with nano-materials technology manufacturer Graphene Composites Ltd to provide the graphene solution in their GC Shield™ armour products. The product is the result of a lengthy development collaboration between the companies together with the Centre for Process Innovation (CPI) using GNP-M grade graphene from Thomas Swan in the final application - an endorsement of the company’s ability to manufacture graphene in volume.

The GC Shield™ comes in a range of armour products providing lightweight, mobile protection to individuals and groups, plus effective protection for installation in large spaces. From a lightweight, flexible shield that is both bullet and stab-proof and can fit into a schoolbag, the GC Shield™ Plus has been successfully tested to stop multiple 7.62 x 51mm NATO M80 sniper bullets and AR-15 assault rifle M193 bullets fired at close range. The GC Shield™ Curtain can be deployed quickly, effectively and safely to provide protection in large spaces (e.g. school cafeterias, open plan areas, entrance halls).

Michael Edwards, head of the Advanced Materials Division at Thomas Swan said “It is always great to see an end-application that transfers into production demonstrating real-life applications for graphene – something that has been evasive in our market to date. As always there is a learning curve to be developed with a willing partner for a go-to market product, but we are always delighted to reach that point”.

Thomas Swan has a patented process to produce Multiple Layer (MLG) and Graphene Nanoplatelets (GNP) in volume at our facility in Consett, UK. Using our patented process of HighShear Liquid Phase Exfoliation licensed from Professor Jonathan Coleman’s work at Trinity College Dublin, we have further enhanced the process using our expertise at Thomas Swan, scaling-up to a 20T per year GNP capacity available today. We have the distinct advantage of being an established global player in the chemicals and materials business.

With manufacturing in the UK, a subsidiary company in the USA together with QA, logistics, regulatory and safety management, we are a leader in the field of 2D materials. Sandy Chen, CEO and founder of Graphene Composites said “Thomas Swan’s expertise in graphene manufacturing has been crucial to our success in developing our revolutionary armour products. Not only has the high quality and consistent manufacture made this possible but as a company, their willingness to collaborate closely with our Technical Team in our development processes has led to innovative and agile product design and development. This has enabled us to get our products market-ready much more quickly”.

Tags:  2D materials  Graphene  Graphene Composites  Jonathan Coleman  Michael Edwards  nanomaterials  Sandy Chen  Thomas Swan 

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Future Ready: The Graphene Innovators

Posted By Graphene Council, The Graphene Council, Saturday, April 6, 2019
Updated: Tuesday, April 2, 2019

When the material graphene, which earned two University of Manchester scientists the Nobel Prize in Physics, exploded onto the research scene in 2004, many thought it was destined to change the world. Bulletproof armour and space elevators, super-antibiotics and rust-proof vehicles were only a few of the imagined applications of graphene, some of which are in development. However, realizing the full impact of the two-dimensional form of carbon carries as much promise as it does challenges.

As people around the globe race to solve the riddle of taking this emerging technology to market, researchers in the lab of McGill Professor Thomas Szkopek had a wave—a sound wave—of inspiration.

Innovation by Example

Szkopek devotes much of his research activity to exploring and exploiting 2D atomic crystals and he is especially curious about graphene. In his Nanoelectronic Devices and Materials lab, he and his students often have impromptu discussions about possible applications for graphene and how they could be developed. “Most of the ideas are bad – but that process is how good ideas get started,” he says. 

Szkopek has always been interested in solving science problems. He looks to his family for the source of his perseverance in the face of challenges. “I inherited a hard work ethic and tolerance for failure. You learn more from your failures than your successes, if you take the time to think about why things failed."

In the lab, he models this determination and inquisitiveness with the goal of fostering innovation—new ideas for problems new or old—and cross-disciplinary solutions. “My job is to allow students to reach their potential and encourage their curiosity. I give students freedom to ask their own questions and pursue their own good ideas. I want to get them out of the mode of being consumers of knowledge and turn them into producers of knowledge.”

He also uses his scientific connections with a diverse network of key players—collaborators from different disciplines, experts in transferring technology from lab to industry, and possible funders—to help students translate and apply new knowledge into practical devices with commercial potential that could benefit society and have a positive impact on people’s daily lives.



As a graduate student at UCLA before arriving at McGill in 2006, Szkopek was encouraged to ask probing physics questions and find practical engineering solutions to difficult problems by his Ph.D. supervisor, electrical engineering professor and physicist Eli Yablonovitch. Szkopek’s mentor introduced a factor that describes light-trapping phenomena, referred to as the “4n2 limit”, which is now used worldwide in almost all commercial solar panels. Yablonovitch was awarded a McGill Honourary Degree in 2018.

“I learned a lot from Eli about trying to reduce problems to their core and asking deep questions about physical limits. I shared an interest in applying physics to technological problems, which is closer to the engineering frontier where things aren’t figured out yet. If you ask good questions, you often find interesting answers. The key is to never lose your curiosity.”

The deep question always at the top of his mind: how to harness the potential of graphene?

A sound idea

During one scientific discussion in the lab, Peter Gaskell, a Ph.D. student who was working with Szkopek on developing lithium-ion batteries made with graphene-treated anodes for electric vehicles, proposed a novel idea about using graphene oxide for an acoustic application: to improve sound quality by using the material in a microphone.

While later sharing a beer with his brother Eric Gaskell, who was doing a Ph.D. in sound engineering at McGill’s Schulich School of Music, Peter floated his idea about graphene and graphene oxide’s mechanical properties and potential application in sound amplification.

Eric, who had worked for Audio Engineering Associates (AEA) in California building ribbon microphones for high-performance studio recording and has been a recording engineer at the Aspen Music Festival, was excited and intrigued. He agreed that graphene oxide might be an ideal material for acoustic membranes in ribbon microphones to enhance sound quality. Its high stiffness could potentially produce better sound with less distortion, while the low-density and lightness could lead to greater energy efficiency.

Peter again pitched the idea to Szkopek and his lab mates. “We couldn’t find any obvious holes in the idea, so we thought it should work,” says Szkopek. The Gaskell brothers proceeded to design, develop and build a graphene oxide membrane for ribbon microphones in his lab.

Szkopek’s initial endorsement and support of the idea, along with access to his lab space, specialized equipment, guidance and expertise in graphene, were invaluable: “Thomas’ enthusiasm for the idea allowed us to take it to the next level,” says Eric.

They successfully created a prototype acoustic membrane for ribbon microphones formed from ultra-thin, flat sheets of graphene oxide-based material, which markedly improved sound quality.

Szkopek encouraged them to explore commercializing the invention.

To start them on their way, Szkopek called Derrick Wong, a Technology Transfer Manager in McGill’s Office of Innovation and Partnerships.

“A key trait for researchers who work with our Office is to be very collaborative, like Thomas”, says Wong. “His personality is to encourage his students to explore and lead, and he provides them with guidance and a skill set.”

Impressed, Wong cautioned that the specific application wasn’t likely to attract funding from investors. “The prototype was cool, but the market for high-end microphones is very limited,” he says.

They discussed other possible applications that could expand the market for graphene oxide membrane technology, including loudspeakers for headphones, a $1.6 billion USD market.

Pivotal prototype funding

The Faculty of Engineering saw the potential of this idea and raised money from donors that enabled Szkopek to develop and pursue it with an Innovation Award for $7,000. “That funding was crucial because it allowed us to hire a summer student to work on developing a prototype for headphones. We didn’t need a million dollars, just thousands,” he says.

Electrical engineering undergraduate Raed Abdo helped devise techniques to form the graphene-based material into cone-shaped loudspeaker membranes for headphones, rather than flat acoustic membranes for microphones.

This turned out to be crucial for attracting investors.
Wong had identified TandemLaunch, a Montreal-based business incubator that specializes in creating start-ups from university research and has strong connections in the consumer electronics and audio industries, as an ideal potential early-stage investor.

He called Tandem and said: “You have to see this prototype.” Four people met with the invention team in Szkopek’s lab and sampled the graphene-based headphones. “They listened and went ‘Wow!’”

Eric would carry the invention forward as an entrepreneur-in-residence, who receives business mentorship, guidance and support in building a technology company. Szkopek would be technical advisor and, as a world-leading graphene scientist, build confidence with investors.

Gaskell joined the incubator in 2016, where he assembled a co-founding team for Ora Graphene Audio, which includes business lead Ari Pinkas and materials lead Sergii Tutashkonko. The start-up received seed funding to develop and commercialize the technology, along with valuable mentoring and infrastructure support. To date, Ora has raised $1 million through Kickstarter and is working closely with several of the biggest consumer electronics brands to develop graphene-based loudspeakers for the audio industry and graphene-based micro speakers for laptops, tablets and cell phones.

Pushing biosensing limits

After Ora’s launch, Szkopek turned his sights to another challenge. He and electrical engineering Ph.D. student Ibrahim Fakih began to explore the potential of graphene’s electronic properties to design and develop a large area, graphene-based field effect transistor for high-precision sensing of ions in water.

“I had been wondering,” says Szkopek, “how could you design a graphene transistor to improve performance in sensing things? Is there an advantage to using graphene and how could you realize that advantage?”

“This device improves the minimum pH detection limits by 20 times over current silicon transistor and glass electrode sensors at a much lower cost. Making the transistor physically larger makes it quieter,” explains Szkopek, who worked with Wong to identify a promising application for commercialization.

Fakih, Szkopek and Abdo co-founded UltraSense, a company that aims to improve water quality monitoring with low-cost, graphene-based sensors.

UltraSense won a 2018 McGill Dobson Cup Award for $10,000 and McGill EngInE prize for $5,000. “Water quality is incredibly important, and I’m excited about the local and global possibilities. Imagine a network of sensors continuously feeding data that gives you the levels of contaminants in water and a map in real time,” says Szkopek.

He recently initiated a collaboration with McGill chemical engineering professor Viviane Yargeau, a leading water quality researcher. “We plan to work with her to test how well the technology functions in a real outdoor environment.”

Seeing is believing

The path from curiosity-driven invention to practical, commercial innovation opens the door to dynamic entrepreneurial and employment opportunities for McGill students and graduates who train and do research. Ora inspired more engineering students in Szkopek’s lab to pursue their entrepreneurial ambitions.

“Ora was an idea and it turned into a new technology company that employs people. That encourages students to go for it. They see that what they do in the lab can turn into something people use in their daily life,” Szkopek says. “This innovation is all being driven by encouraging students’ curiosity, and by providing the resources and environment so they can develop their ideas. The world is changing and there are now more opportunities for students and graduates to build or contribute to their own start-up companies. The future is in their hands.”

Tags:  2D materials  biosensors  Eli Yablonovitch  Eric Gaskell  Graphene  McGill University  nanomaterials  Peter Gaskell  Thomas Szkopek 

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Strategic Insight Paper Explores Graphene's Impact

Posted By Graphene Council, The Graphene Council, Monday, March 25, 2019
Updated: Thursday, March 21, 2019
The International Sign Association (ISA)  is marking its 75th anniversary by giving back to the sign, graphics and visual communications industry. A series of white papers will explore future technologies expected to impact the industry.

The first Strategic Insight paper, Nanomaterials: Giant Changes Coming from the Tiniest of Materials, was written by Dexter Johnson, senior science editor/analyst for the Graphene Council. It explores nanomaterials and their potential uses in protective applications, thin-film electronics (i.e. flexible displays and electronics), digital displays, pigments for inks and paper.

"ISA was founded in 1944 by visionaries who wanted to see how they could grow the industry and their businesses," said Lori Anderson, ISA president and CEO. "As we mark the 75th anniversary, it only seems fitting that we honor their legacy by looking forward as well. These Strategic Insight papers, written by leading thinkers from inside and outside our industry, will help companies explore the next iteration of the sign, graphics and visual communications industry in a way that honors our founders."

Tags:  Graphene  International Sign Association  nanomaterials  The Graphene Council 

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Micro and nano materials, including clothing for Olympic athletes

Posted By Graphene Council, The Graphene Council, Monday, March 25, 2019
Updated: Monday, March 25, 2019
A research team of materials engineers and performance scientists at Swansea University has been awarded £1.8 million to develop new products - in areas from the motor industry to packaging and sport - that make use of micro and nano materials based on specialist inks.

One application already being developed is specialist clothing that will be worn by elite British athletes in training and at the 2020 Olympic and Paralympic Games.

The researchers will be incorporating advanced materials such as graphene into flexible coatings which will be printed and embedded into bespoke garments to enhance the performance of elite athletes.

The purpose of the project is to serve as a pipeline for new ideas, testing to see which of them can work in practice and on a large scale, and then turning them into actual products.

The gap between initial concept and final product is known in manufacturing as the "valley of death" as so many good ideas simply fail to make it. The pipeline will help ensure more of them make it across the valley: off the drawing board and into production.

This project is unique in that it is driven by market requirements. As well as the wearable technology, identified by the English Institute of Sport (EIS), two other areas will be amongst the first to use the pipeline: SMART packaging, with the company Tectonic, and the car industry, with GTS Flexible Materials

The project is a collaboration between two teams in Swansea University's College of Engineering: the Welsh Centre for Printing and Coating (WCPC) led by Professor Tim Claypole and Professor David Gethin, and the Elite and Professional Sport (EPS) research group, namely Dr Neil Bezodis, Professor Liam Kilduff and Dr Camilla Knight.

The WCPC is pioneering ways of using printing with specialist inks as an advanced manufacturing process. Their expertise will be central to the project.

Professor Tim Claypole, Director of the Wales Centre for Printing and Coating, said:

"The WCPC expertise in ink formulation and printing is enabling the creation of a range of advanced products for a wide range of applications that utilise innovative materials".

Sport, which is one of the areas the project covers, has been a test bed for technology before. For example, heart rate monitors and exercise bikes have now become mainstream.

EPS project lead Dr Neil Bezodis underlined the importance of links with partners within the overall project:

"Collaborations between industrial partners which are driven by end users in elite sport are key to ensuring our research has a real impact".

Tags:  Camilla Knight  coatings  David Gethin  Graphene  Liam Kilduff  nanomaterials  Neil Bezodis  sporting goods  Swansea University  Tim Claypole  Welsh Centre for Printing and Coating 

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Directed evolution builds nanoparticles

Posted By Graphene Council, The Graphene Council, Thursday, March 7, 2019
Updated: Friday, March 1, 2019

The 2018 Nobel Prize in Chemistry went to three scientists who developed the method that forever changed protein engineering: directed evolution. Mimicking natural evolution, directed evolution guides the synthesis of proteins with improved or new functions.

First, the original protein is mutated to create a collection of mutant protein variants. The protein variants that show improved or more desirable functions are selected. These selected proteins are then once more mutated to create another collection of protein variants for another round of selection. This cycle is repeated until a final, mutated protein is evolved with optimized performance compared to the original protein.

Now, scientists from the lab of Ardemis Boghossian at EPFL, have been able to use directed evolution to build not proteins, but synthetic nanoparticles (Chemical Communications, "Directed evolution of the optoelectronic properties of synthetic nanomaterials").

These nanoparticles are used as optical biosensors – tiny devices that use light to detect biological molecules in air, water, or blood. Optical biosensors are widely used in biological research, drug development, and medical diagnostics, such as real-time monitoring of insulin and glucose in diabetics.

“The beauty of directed evolution is that we can engineer a protein without even knowing how its structure is related to its function,” says Boghossian. “And we don't even have this information for the vast, vast majority of proteins.”

Her group used directed evolution to modify the optoelectronic properties of DNA-wrapped single-walled carbon nanotubes (or, DNA-SWCNTs, as they are abbreviated), which are nano-sized tubes of carbon atoms that resemble rolled up sheets of graphene covered by DNA. When they detect their target, the DNA-SWCNTs emit an optical signal that can penetrate through complex biological fluids, like blood or urine.

Using a directed evolution approach, Boghossian’s team was able to engineer new DNA-SWCNTs with optical signals that are increased by up to 56% – and they did it over only two evolution cycles.

“The majority of researchers in this field just screen large libraries of different materials in hopes of finding one with the properties they are looking for,” says Boghossian. “In optical nanosensors, we try to improve properties like selectivity, brightness, and sensitivity. By applying directed evolution, we provide researchers with a guided approach to engineering these nanosensors.”

The study shows that what is essentially a bioengineering technique can be used to more rationally tune the optoelectronic properties of certain nanomaterials.

Boghossian explains: “Fields like materials science and physics are mostly preoccupied with defining material structure-function relationships, making materials that lack this information difficult to engineer. But this is a problem that nature solved billions of years ago – and, in recent decades, biologists have tackled it as well. I think our study shows that as materials scientists and physicists, we can still learn a few pragmatic lessons from biologists.”

Tags:  Ardemis Boghossian  biosensors  DNA  EPFL  Graphene  nanomaterials  optoelectronics 

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Contract awarded to develop graphene ink-based heaters for gas pre-heating

Posted By Graphene Council, The Graphene Council, Wednesday, March 6, 2019
Updated: Wednesday, March 6, 2019
Haydale, is pleased to announce it will be collaborating with Northern Gas Networks (NGN) and the Energy Innovation Centre, on a study to investigate the feasibility of developing a modern, innovative, fully compliant graphene-based preheat solution for use on gas operational sites.
 
The graphene solution has the potential to be more efficient and reliable than existing systems and has in-built flexibility to either retrofit onto existing pipes or to be built into new heat exchangers. Phase One of the 30-week project will see Haydale working directly with NGN, the gas distributer for the North East, Northern Cumbria and much of Yorkshire.
 
Modern gas pre-heating systems, whilst more efficient than traditional Water Bath Heaters (WBHs), have larger electrical power requirements and require backup generators to remain operational in the event of a power cut. Maintaining gas supplies is of vital importance to the Gas Distribution Networks and as such, backup power is used to ensure that sites can remain operational should the electrical supply be interrupted.  
 
WBHs are gas-powered and use low voltage solenoids in their control, so can remain operational from the very low voltage (VLV) supply which is backed up by batteries on site. WBHs however can be considered inefficient both environmentally and in terms of heat transfer.
 
Development of graphene-based, high conductivity inks and coatings that can be applied to surfaces have the potential to provide even heating across large areas with a very thin profile. This technology is made possible by Haydale’s patented HDPlas process which promotes efficient dispersion of nanomaterials into polymers and carriers. 
 
With this innovative technology, flexible construction methods have the potential for several different solutions such as external fitment to existing pipes, internal fitment to existing pipes or integration into new replacement composite pipe sections which may include heat-exchanging internal surfaces. 
 
Should this initial feasibility project prove successful, future development stages will progress to field-based trials.
 
Dr Matthew Thornton, Senior Manager for Haydale Composite Solutions, said: “We are excited to be working with NGN and EIC to develop our graphene-based heater technology for use on the gas distribution network. The opportunity to demonstrate the feasibility of graphene-based heaters as a viable alternative to incumbent pre-heat systems presents a fantastic opportunity for Haydale in this innovative sector.”

Keith Broadbent, COO for Haydale, said: “This solution for the gas networks shows another commercial route for the functionalised graphene inks that are being produced by Haydale. We look forward to working with both Northern Gas Networks and the Energy Innovation Centre to progress this route to market.”
 
Gareth Payne, Project Manager for Northern Gas Networks, said: “I’m really excited to be leading this project on behalf of NGN, working with Haydale Composite Solutions and supported by the EIC. If this project proves successful, then we could be looking at a real game changer in terms of preheating systems that can be utilised on gas distribution sites. We hope this project will lead to collaborative working with other networks to develop the idea further, as NGN continues to explore low-carbon technologies in order to deliver a cleaner, greener future for customers.”

David Turner-Bennett, Gas Innovation Engineer for the Energy Innovation Centre, said: “We are thrilled to be facilitating this project with NGN and Haydale. This project has the potential to revolutionise pre-heating systems in the gas industry and demonstrates NGN’s commitment to securing a low-carbon future. It’s a pleasure to work with and support a ground-breaking project that involves people like Gareth and Matthew who are passionate about change. We hope to see other networks follow NGN’s lead and collaborate to develop this idea further.”

Tags:  Graphene  Haydale  Keith Broadbent  Matthew Thornton  nanomaterials  Northern Gas Networks 

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A new 'periodic table' for nanomaterials

Posted By Graphene Council, The Graphene Council, Monday, February 18, 2019

The approach was developed by Daniel Packwood of Kyoto University's Institute for Integrated Cell-Material Sciences (iCeMS) and Taro Hitosugi of the Tokyo Institute of Technology. It involves connecting the chemical properties of molecules with the nanostructures that form as a result of their interaction. A machine learning technique generates data that is then used to develop a diagram that categorizes different molecules according to the nano-sized shapes they form. This approach could help materials scientists identify the appropriate molecules to use in order to synthesize target nanomaterials.

Fabricating nanomaterials using a bottom-up approach requires finding 'precursor molecules' that interact and align correctly with each other as they self-assemble. But it's been a major challenge knowing how precursor molecules will interact and what shapes they will form.

Bottom-up fabrication of graphene nanoribbons is receiving much attention due to their potential use in electronics, tissue engineering, construction, and bio-imaging. One way to synthesise them is by using bianthracene precursor molecules that have bromine 'functional' groups attached to them. The bromine groups interact with a copper substrate to form nano-sized chains. When these chains are heated, they turn into graphene nanoribbons.

Packwood and Hitosugi tested their simulator using this method for building graphene nanoribbons.

Data was input into the model about the chemical properties of a variety of molecules that can be attached to bianthracene to 'functionalize' it and facilitate its interaction with copper. The data went through a series of processes that ultimately led to the formation of a 'dendrogram'.

This showed that attaching hydrogen molecules to bianthracene led to the development of strong one-dimensional nano-chains. Fluorine, bromine, chlorine, amidogen, and vinyl functional groups led to the formation of moderately strong nano-chains. Trifluoromethyl and methyl functional groups led to the formation of weak one-dimensional islands of molecules, and hydroxide and aldehyde groups led to the formation of strong two-dimensional tile-shaped islands.

The information produced in the dendogram changed based on the temperature data provided. The above categories apply when the interactions are conducted at -73°C. The results changed with warmer temperatures. The researchers recommend applying the data at low temperatures where the effect of the functional groups' chemical properties on nano-shapes are most clear.

The technique can be applied to other substrates and precursor molecules. The researchers describe their method as analogous to the periodic table of chemical elements, which groups atoms based on how they bond to each other. "However, in order to truly prove that the dendrograms or other informatics-based approaches can be as valuable to materials science as the periodic table, we must incorporate them in a real bottom-up nanomaterial fabrication experiment," the researchers conclude in their study. "We are currently pursuing this direction in our laboratories."

Tags:  Daniel Packwood  Graphene  Graphene Nanoribbons  Kyoto University  nanomaterials  Taro Hitosugi  Tokyo Institute of Technology 

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