̽��ֱ�� of Cambridge - Tawfique Hasan

Sensors made from ‘frozen smoke’ can detect toxic formaldehyde in homes and offices

sc604 — Fri, 09 Feb 2024 19:00:00 +0000

̽��ֱ��researchers, from the ̽��ֱ�� of Cambridge, developed sensors made from highly porous materials known as aerogels. By precisely engineering the shape of the holes in the aerogels, the sensors were able to detect the fingerprint of formaldehyde, a common indoor air pollutant, at room temperature.

̽��ֱ��proof-of-concept sensors, which require minimal power, could be adapted to detect a wide range of hazardous gases, and could also be miniaturised for wearable and healthcare applications. ̽��ֱ��results are reported in the journal Science Advances.

Volatile organic compounds (VOCs) are a major source of indoor air pollution, causing watery eyes, burning in the eyes and throat, and difficulty breathing at elevated levels. High concentrations can trigger attacks in people with asthma, and prolonged exposure may cause certain cancers.

Formaldehyde is a common VOC and is emitted by household items including pressed wood products (such as MDF), wallpapers and paints, and some synthetic fabrics. For the most part, the levels of formaldehyde emitted by these items are low, but levels can build up over time, especially in garages where paints and other formaldehyde-emitting products are more likely to be stored.

According to a 2019 report from the campaign group Clean Air Day, a fifth of households in the UK showed notable concentrations of formaldehyde, with 13% of residences surpassing the recommended limit set by the World Health Organization (WHO).

“VOCs such as formaldehyde can lead to serious health problems with prolonged exposure even at low concentrations, but current sensors don’t have the sensitivity or selectivity to distinguish between VOCs that have different impacts on health,” said Professor Tawfique Hasan from the Cambridge Graphene Centre, who led the research.

“We wanted to develop a sensor that is small and doesn’t use much power, but can selectively detect formaldehyde at low concentrations,” said Zhuo Chen, the paper’s first author.

̽��ֱ��researchers based their sensors on aerogels: ultra-light materials sometimes referred to as ‘liquid smoke’, since they are more than 99% air by volume. ̽��ֱ��open structure of aerogels allows gases to easily move in and out. By precisely engineering the shape, or morphology, of the holes, the aerogels can act as highly effective sensors.

Working with colleagues at Warwick ̽��ֱ��, the Cambridge researchers optimised the composition and structure of the aerogels to increase their sensitivity to formaldehyde, making them into filaments about three times the width of a human hair. ̽��ֱ��researchers 3D printed lines of a paste made from graphene, a two-dimensional form of carbon, and then freeze-dried the graphene paste to form the holes in the final aerogel structure. ̽��ֱ��aerogels also incorporate tiny semiconductors known as quantum dots.

̽��ֱ��sensors they developed were able to detect formaldehyde at concentrations as low as eight parts per billion, which is 0.4 percent of the level deemed safe in UK workplaces. ̽��ֱ��sensors also work at room temperature, consuming very low power.

“Traditional gas sensors need to be heated up, but because of the way we’ve engineered the materials, our sensors work incredibly well at room temperature, so they use between 10 and 100 times less power than other sensors,” said Chen.

To improve selectivity, the researchers then incorporated machine learning algorithms into the sensors. ̽��ֱ��algorithms were trained to detect the ‘fingerprint’ of different gases, so that the sensor was able to distinguish the fingerprint of formaldehyde from other VOCs.

“Existing VOC detectors are blunt instruments – you only get one number for the overall concentration in the air,” said Hasan. “By building a sensor that can detect specific VOCs at very low concentrations in real time, it can give home and business owners a more accurate picture of air quality and any potential health risks.”

̽��ֱ��researchers say the same technique could be used to develop sensors to detect other VOCs. In theory, a device the size of a standard household carbon monoxide detector could incorporate multiple different sensors within it, providing real-time information about a range of different hazardous gases. “At Warwick, we're developing a low-cost multi-sensor platform that will incorporate these new aerogel materials and, coupled with AI algorithms, detect different VOCs,” said co-author Professor Julian Gardner from Warwick ̽��ֱ��.

“By using highly porous materials as the sensing element, we’re opening up whole new ways of detecting hazardous materials in our environment,” said Chen.

̽��ֱ��research was supported in part by the Henry Royce Institute, and the Engineering and Physical Sciences Research Council (EPSRC), part of UK Research and Innovation (UKRI). Tawfique Hasan is a Fellow of Churchill College, Cambridge.

Reference:
Zhuo Chen et al. ‘Real-time, noise and drift resilient formaldehyde sensing at room temperature with aerogel filaments.’ Science Advances (2024). DOI: 10.1126/sciadv.adk6856

Researchers have developed a sensor made from ‘frozen smoke’ that uses artificial intelligence techniques to detect formaldehyde in real time at concentrations as low as eight parts per billion, far beyond the sensitivity of most indoor air quality sensors.

NASA/JPL-Caltech

Silica aerogel

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Artificial intelligence powers record-breaking all-in-one miniature spectrometers

sc604 — Thu, 20 Oct 2022 18:00:00 +0000

We see light and colours around us every day. However, to analyse the information it carries, we must analyse light using spectrometers, in the lab. These devices detect sparkles and substances that our eyes would otherwise not notice.

Now, an international team of researchers, including the ̽��ֱ�� of Cambridge, have designed a miniaturised spectrometer that breaks all current resolution records, and does so in a much smaller package, thanks to computational programmes and artificial intelligence.

̽��ֱ��new miniaturised devices could be used in a broad range of sectors, from checking the quality of food to analysing starlight or detecting faint clues of life in outer space. ̽��ֱ��results are reported in the journal Science.

Traditionally, spectrometers rely on bulky components to filter and disperse light. Modern approaches simplify these components to shrink footprints, but still suffer from limited resolution and bandwidth. Additionally, traditional spectrometers are heavy and take up extraordinary amounts of space, which limits their applications in portable and mobile devices.

To tackle these problems, and shrink the size of the system, researchers have coupled layered materials with artificial intelligence algorithms. ̽��ֱ��result is an all-in-one spectrometer thousands of times smaller than current commercial systems. At the same time, it offers performance comparable to benchtop systems. In other words, these new spectrometers will provide portable alternatives to uncover otherwise invisible information, without even going into the lab.

“We eliminate the need for detector arrays, dispersive components, and filters. It’s an all-in-one, miniaturised device that could revolutionise this field,” said Dr Hoon Hahn Yoon, from Aalto ̽��ֱ�� in Finland, first author of the paper. This spectrometer-on-chip technology is expected to offer high performance and new usability across science and industry.

̽��ֱ��detector uses van der Waals heterostructures – a ‘sandwich’ of different ingredients, including graphene, molybdenum disulfide, and tungsten diselenide. Different combinations of material components enable light detection beyond the visible spectrum, as far as the near-infrared region. This means the spectrometer detects more than just colour, enabling applications such as chemical analysis and night vision.

“We detect a continuum spectrum of light, opening a world of possibilities in a myriad of markets,” said Yoon. “Exploring other material combinations could uncover further functionalities, including even broader hyperspectral detection and improved resolution.”

Artificial intelligence is a key aspect of these devices, commonly called ‘computational’ spectrometers. This technology compensates for the inherent noise increase that inevitably occurs when the optical component is wholly removed.

“We were able to use mathematical algorithms to successfully reconstruct the signals and spectra, it’s a profound and transformative technological leap,” said lead author Professor Zhipei Sun, also from Aalto ̽��ֱ��, and a former member of Cambridge’s Department of Engineering. “ ̽��ֱ��current design is just a proof-of-concept. More advanced algorithms, as well as different combinations of materials, could soon provide even better miniaturised spectrometers.”

Spectrometers are used for toxin detection in food and cosmetics, cancer imaging, and in spacecraft – including the James Webb Space Telescope. And they will soon become more common thanks to the development and advancement of technologies such as the Internet of Things and Industry 4.0.

̽��ֱ��detection of light – and the full analysis of spectroscopic information – has applications in sensing, surveillance, smart agriculture, and more. Among the most promising applications for miniaturised spectrometers are chemical and biochemical analysis, thanks to the capabilities of the devices to detect light in the infrared wavelength range.

̽��ֱ��new devices could be incorporated into instruments like drones, mobile phones, and lab-on-a-chip platforms, which can carry out several experiments in a single integrated circuit. ̽��ֱ��latter also opens up opportunities in healthcare. In this field, spectrometers and light-detectors are already key components of imaging and diagnostic systems – the new miniaturised devices could enable the simultaneous visualisation and detection of ‘chemical fingerprints’, leading to possibilities in the biomedical area.

“Our miniaturised spectrometers offer high spatial and spectral resolution at the micrometre and nanometre scales, which is particularly exciting for responsive bio-implants and innovative imaging techniques,” said co-author Professor Tawfique Hasan, from the Cambridge Graphene Centre.

This technology has huge potential for scalability and integration, thanks to its compatibility with well-established industrial processes. It could open up the future for the next generation of smartphone cameras that evolve into hyperspectral cameras that conventional colour cameras cannot do. Researchers hope their contribution is a stepping stone towards the development of more advanced computational spectrometers, with record-breaking accuracy and resolution. This example, they say, is just the first of many.

Reference:
Hoon Hahn Yoon et al. ‘Miniaturized Spectrometers with a Tunable van der Waals Junction.’ Science (2022). DOI: 10.1126/science.add8544.

Using Artificial Intelligence (AI) to replace optical and mechanical components, researchers have designed a tiny spectrometer that breaks all current resolution records.

Suvi-Tuuli Akkanen, Mikko Turunen, Vincent Pelgrin. Aalto ̽��ֱ��.

On-chip spectrometer on a fingertip

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

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Coffee stains inspire optimal printing technique for electronics

Anonymous — Wed, 12 Aug 2020 18:00:00 +0000

Have you ever spilled your coffee on your desk? You may then have observed one of the most puzzling phenomena of fluid mechanics – the coffee ring effect. This effect has hindered the industrial deployment of functional inks with graphene, 2D materials, and nanoparticles because it makes printed electronic devices behave irregularly.

Now, after studying this process for years, a team of researchers have created a new family of inks that overcomes this problem, enabling the fabrication of new electronics such as sensors, light detectors, batteries and solar cells.

Coffee rings form because the liquid evaporates quicker at the edges, causing an accumulation of solid particles that results in the characteristic dark ring. Inks behave like coffee – particles in the ink accumulate around the edges creating irregular shapes and uneven surfaces, especially when printing on hard surfaces like silicon wafers or plastics.

Researchers, led by Tawfique Hasan from the Cambridge Graphene Centre of the ̽��ֱ�� of Cambridge, with Colin Bain from the Department of Chemistry of Durham ̽��ֱ��, and Meng Zhang from School of Electronic and Information Engineering of Beihang ̽��ֱ��, studied the physics of ink droplets combining particle tracking in high-speed micro-photography, fluid mechanics, and different combinations of solvents.

Their solution: alcohol, specifically a mixture of isopropyl alcohol and 2-butanol. Using these, ink particles tend to distribute evenly across the droplet, generating shapes with uniform thickness and properties. Their results are reported in the journal Science Advances.

“ ̽��ֱ��natural form of ink droplets is spherical – however, because of their composition, our ink droplets adopt pancake shapes,” said Hasan.

While drying, the new ink droplets deform smoothly across the surface, spreading particles consistently. Using this universal formulation, manufacturers could adopt inkjet printing as a cheap, easy-to-access strategy for the fabrication of electronic devices and sensors. ̽��ֱ��new inks also avoid the use of polymers or surfactants – commercial additives used to tackle the coffee ring effect, but at the same time thwart the electronic properties of graphene and other 2D materials.

Most importantly, the new methodology enables reproducibility and scalability – researchers managed to print 4500 nearly identical devices on a silicon wafer and plastic substrate. In particular, they printed gas sensors and photodetectors, both displaying very little variations in performance. Previously, printing a few hundred such devices was considered a success, even if they showed uneven behaviour.

“Understanding this fundamental behaviour of ink droplets has allowed us to find this ideal solution for inkjet printing all kinds of two-dimensional crystals,” said first author Guohua Hu. “Our formulation can be easily scaled up to print new electronic devices on silicon wafers, or plastics, and even in spray painting and wearables, already matching or exceeding the manufacturability requirements for printed devices.”

Beyond graphene, the team has optimised over a dozen ink formulations containing different materials. Some of them are graphene two-dimensional ‘cousins’ such as black phosphorus and boron nitride, others are more complex structures like heterostructures – ‘sandwiches’ of different 2D materials – and nanostructured materials. Researchers say their ink formulations can also print pure nanoparticles and organic molecules.This variety of materials could boost the manufacturing of electronic and photonic devices, as well as more efficient catalysts, solar cells, batteries and functional coatings.

̽��ֱ��team expects to see industrial applications of this technology very soon. Their first proofs of concept – printed sensors and photodetectors – have shown promising results in terms of sensitivity and consistency, exceeding the usual industry requirements. This should attract investors interested in printed and flexible electronics.

“Our technology could speed up the adoption of inexpensive, low-power, ultra-connected sensors for the internet of things,” said Hasan. “ ̽��ֱ��dream of smart cities will come true.”

̽��ֱ��research was funded by the EPSRC, InnovateUK and the Royal Society.

Reference:
G. Hu et al. ‘A general ink formulation of 2D crystals for wafer-scale inkjet printing.’ Science Advances (2020). DOI: 10.1126/sciadv.aba5029.

Using an alcohol mixture, researchers modified how ink droplets dry, enabling cheap industrial-scale printing of electronic devices at unprecedented scales.

̽��ֱ��natural form of ink droplets is spherical – however, because of their composition, our ink droplets behave like pancakes

Tawfique Hasan

Drying droplets: the red arrows showing the end of the particle trajetories

Yes

Nanowires replace Newton’s famous glass prism

sc604 — Thu, 05 Sep 2019 18:00:00 +0000

̽��ֱ��device, made from a single nanowire 1000 times thinner than a human hair, is the smallest spectrometer ever designed. It could be used in potential applications such as assessing the freshness of foods, the quality of drugs, or even identifying counterfeit objects, all from a smartphone camera. Details are reported in the journal Science.

In the 17^th century, Isaac Newton, through his observations on the splitting of light by a prism, sowed the seeds for a new field of science studying the interactions between light and matter – spectroscopy. Today, optical spectrometers are essential tools in industry and almost all fields of scientific research. Through analysing the characteristics of light, spectrometers can tell us about the processes within galactic nebulae, millions of light years away, down to the characteristics of protein molecules.

However, even now, the majority of spectrometers are based around principles similar to what Newton demonstrated with his prism: the spatial separation of light into different spectral components. Such a basis fundamentally limits the size of spectrometers in respect: they are usually bulky and complex, and challenging to shrink to sizes much smaller than a coin. Four hundred years after Newton, ̽��ֱ�� of Cambridge researchers have overcome this challenge to produce a system up to a thousand times smaller than those previously reported.

̽��ֱ��Cambridge team, working with colleagues from the UK, China and Finland, used a nanowire whose material composition is varied along its length, enabling it to be responsive to different colours of light across the visible spectrum. Using techniques similar to those used for the manufacture of computer chips, they then created a series of light-responsive sections on this nanowire.

“We engineered a nanowire that allows us to get rid of the dispersive elements, like a prism, producing a far simpler, ultra-miniaturised system than conventional spectrometers can allow,” said first author Zongyin Yang from the Cambridge Graphene Centre. “ ̽��ֱ��individual responses we get from the nanowire sections can then be directly fed into a computer algorithm to reconstruct the incident light spectrum.”

“When you take a photograph, the information stored in pixels is generally limited to just three components – red, green, and blue,” said co-first author Tom Albrow-Owen. “With our device, every pixel contains data points from across the visible spectrum, so we can acquire detailed information far beyond the colours which our eyes can perceive. This can tell us, for instance, about chemical processes occurring in the frame of the image.”

“Our approach could allow unprecedented miniaturisation of spectroscopic devices, to an extent that could see them incorporated directly into smartphones, bringing powerful analytical technologies from the lab to the palm of our hands,” said Dr Tawfique Hasan, who led the study.

One of the most promising potential uses of the nanowire could be in biology. Since the device is so tiny, it can directly image single cells without the need for a microscope. And unlike other bioimaging techniques, the information obtained by the nanowire spectrometer contains a detailed analysis of the chemical fingerprint of each pixel.

̽��ֱ��researchers hope that the platform they have created could lead to an entirely new generation of ultra-compact spectrometers working from the ultraviolet to the infrared range. Such technologies could be used for a wide range of consumer, research and industrial applications, including in lab-on-a-chip systems, biological implants, and smart wearable devices.

̽��ֱ��Cambridge team has filed a patent on the technology, and hopes to see real-life applications within the next five years.

Reference:
Zongyin Yang et al. ‘Single nanowire spectrometers.’ Science (2019). DOI: 10.1126/science.aax8814

Scientists have designed an ultra-miniaturised device that could image single cells without the need for a microscope or make chemical fingerprint analysis possible from within a smartphone camera.

Our approach could bring powerful analytical technologies from the lab to the palm of our hands

Tawfique Hasan

Ella Maru Studio

Artist's impression of single-nanowire spectrometer

Yes

Leaf vein structure could hold key to extending battery life

ps748 — Thu, 06 Apr 2017 14:05:11 +0000

̽��ֱ��researchers have designed a porous material that utilises a vascular structure, such as that found in the veins of a leaf, and could make energy transfers more efficient. ̽��ֱ��material could improve the performance of rechargeable batteries, optimizing the charge and discharge process and relieving stresses within the battery electrodes, which, at the moment, limit their life span. ̽��ֱ��same material could be used for high performance gas sensing or for catalysis to break down organic pollutants in water.

To design this bio-inspired material, an international team comprising scientists from China, the United Kingdom, United States and Belgium is mimicking the rule known as ‘Murray’s Law’ which helps natural organisms survive and grow. According to this Law, the entire network of pores existing on different scales in such biological systems is interconnected in a way to facilitate the transfer of liquids and minimize resistance throughout the network. ̽��ֱ��plant stems of a tree, or leaf veins, for example, optimize the flow of nutrients for photosynthesis with both high efficiency and minimum energy consumption by regularly branching out to smaller scales. In the same way, the surface area of the tracheal pores of insects remains constant along the diffusion pathway to maximize the delivery of carbon dioxide and oxygen in gaseous forms.

̽��ֱ��team, led by Prof Bao-Lian Su, a life member of Clare Hall, ̽��ֱ�� of Cambridge and who is also based at Wuhan ̽��ֱ�� of Technology in China and at the ̽��ֱ�� of Namur in Belgium, adapted Murray’s Law for the fabrication of the first ever synthetic ‘Murray material’ and applied it to three processes: photocatalysis, gas sensing and lithium ion battery electrodes. In each, they found that the multi-scale porous networks of their synthetic material significantly enhanced the performance of these processes.

Prof Su says:

“This study demonstrates that by adapting Murray’s Law from biology and applying it to chemistry, the performance of materials can be improved significantly. ̽��ֱ��adaptation could benefit a wide range of porous materials and improve functional ceramics and nano-metals used for energy and environmental applications.”

“ ̽��ֱ��introduction of the concept of Murray’s Law to industrial processes could revolutionize the design of reactors with highly enhanced efficiency, minimum energy, time, and raw material consumption for a sustainable future.”

Writing in Nature Communications this week, the team describes how it used zinc oxide (ZnO) nanoparticles as the primary building block of their Murray material. These nanoparticles, containing small pores within them, form the lowest level of the porous network. ̽��ֱ��team arranged the ZnO particles through a layer-by layer evaporation-driven self-assembly process. This creates a second level of porous networks between the particles. During the evaporation process, the particles also form larger pores due to solvent evaporation, which represents the top level of pores, resulting in a three level Murray material. ̽��ֱ��team successfully fabricated these porous structures with the precise diameter ratios required to obey Murray’s law, enabling the efficient transfer of materials across the multilevel pore network.

Co-author, Dr Tawfique Hasan, of the Cambridge Graphene Centre, part of the ̽��ֱ��’s Department of Engineering, adds:

“This very first demonstration of a Murray material fabrication process is incredibly simple and is entirely driven by the nanoparticle self-assembly. Large scale manufacturability of this porous material is possible, making it an exciting, enabling technology, with potential impact across many applications.”

With its synthetic Murray material, with precise diameter ratios between the pore levels, the team demonstrated an efficient breakdown of an organic dye in water by using photocatalysis. This showed it was easy for the dye to enter the porous network leading to efficient and repeated reaction cycles. ̽��ֱ��team also used the same Murray material with a structure similar to the breathing networks of insects, for fast and sensitive gas detection with high repeatability.

̽��ֱ��team proved that its Murray material can significantly improve the long term stability and fast charge/discharge capability for lithium ion storage, with a capacity improvement of up to 25 times compared to state of the art graphite material currently used in lithium ion battery electrodes. ̽��ֱ��hierarchical nature of the pores also reduces the stresses in these electrodes during the charge/discharge processes, improving their structural stability and resulting in a longer life time for energy storage devices.

̽��ֱ��team envisions that the strategy could be used effectively in materials designs for energy and environmental applications.

̽��ֱ��research was partially supported by the Royal Academy of Engineering.

Reference

Xianfeng Zheng et al: ‘Bio-inspired Murray materials for mass transfer and activity’ Nature Communications 6th April 2017

DOI:10.1038/ncomms14921

̽��ֱ��natural structure found within leaves could improve the performance of everything from rechargeable batteries to high-performance gas sensors, according to an international team of scientists.

the adaptation could benefit a wide range of porous materials

Prof Bao-Lian Su

Christoph Rupprecht

Close-up of a leaf showing its veins

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New graphene based inks for high-speed manufacturing of printed electronics

sc604 — Mon, 19 Oct 2015 10:38:54 +0000

A low-cost, high-speed method for printing graphene inks using a conventional roll-to-roll printing process, like that used to print newspapers and crisp packets, could open up a wide range of practical applications, including inexpensive printed electronics, intelligent packaging and disposable sensors.

Developed by researchers at the ̽��ֱ�� of Cambridge in collaboration with Cambridge-based technology company Novalia, the method allows graphene and other electrically conducting materials to be added to conventional water-based inks and printed using typical commercial equipment, the first time that graphene has been used for printing on a large-scale commercial printing press at high speed.

Graphene is a two-dimensional sheet of carbon atoms, just one atom thick. Its flexibility, optical transparency and electrical conductivity make it suitable for a wide range of applications, including printed electronics. Although numerous laboratory prototypes have been demonstrated around the world, widespread commercial use of graphene is yet to be realised.

“We are pleased to be the first to bring graphene inks close to real-world manufacturing. There are lots of companies that have produced graphene inks, but none of them has done it on a scale close to this,” said Dr Tawfique Hasan of the Cambridge Graphene Centre (CGC), who developed the method. “Being able to produce conductive inks that could effortlessly be used for printing at a commercial scale at a very high speed will open up all kinds of different applications for graphene and other similar materials.”

“This method will allow us to put electronic systems into entirely unexpected shapes,” said Chris Jones of Novalia. “It’s an incredibly flexible enabling technology.”

Hasan’s method, developed at the ̽��ֱ��’s Nanoscience Centre, works by suspending tiny particles of graphene in a ‘carrier’ solvent mixture, which is added to conductive water-based ink formulations. ̽��ֱ��ratio of the ingredients can be adjusted to control the liquid’s properties, allowing the carrier solvent to be easily mixed into a conventional conductive water-based ink to significantly reduce the resistance. ̽��ֱ��same method works for materials other than graphene, including metallic, semiconducting and insulating nanoparticles.

Currently, printed conductive patterns use a combination of poorly conducting carbon with other materials, most commonly silver, which is expensive. Silver-based inks cost £1000 or more per kilogram, whereas this new graphene ink formulation would be 25 times cheaper. Additionally, silver is not recyclable, while graphene and other carbon materials can easily be recycled. ̽��ֱ��new method uses cheap, non-toxic and environmentally friendly solvents that can be dried quickly at room temperature, reducing energy costs for ink curing. Once dry, the ‘electric ink’ is also waterproof and adheres to its substrate extremely well.

̽��ֱ��graphene-based inks have been printed at a rate of more than 100 metres per minute, which is in line with commercial production rates for graphics printing, and far faster than earlier prototypes. Two years ago, Hasan and his colleagues produced a prototype of a transparent and flexible piano using graphene-based inks, which took between six and eight hours to make. Through the use of this new ink, more versatile devices on paper or plastic can be made at a rate of 300 per minute, at a very low cost. Novalia has also produced a printed DJ deck and an interactive poster, which functions as a drum kit using the same method.

Hasan and PhD students Guohua Hu, Richard Howe and Zongyin Yang of the Hybrid Nanomaterials Engineering group at CGC, in collaboration with Novalia, tested the method on a typical commercial printing press, which required no modifications in order to print with the graphene ink. In addition to the new applications the method will open up for graphene, it could also initiate entirely new business opportunities for commercial graphics printers, who could diversify into the electronics sector.

“ ̽��ֱ��UK, and the Cambridge area in particular, has always been strong in the printing sector, but mostly for graphics printing and packaging,” said Hasan, a Royal Academy of Engineering Research Fellow and a ̽��ֱ�� Lecturer in the Engineering Department. “We hope to use this strong local expertise to expand our functional ink platform. In addition to cheaper printable electronics, this technology opens up potential application areas such as smart packaging and disposable sensors, which to date have largely been inaccessible due to cost.”

In the short to medium term, the researchers hope to use their method to make printed, disposable biosensors, energy harvesters and RFID tags.

̽��ֱ��research was supported by grants from the Engineering and Physical Sciences Research Council's Impact Acceleration Account and a Royal Academy of Engineering Research Fellowship. ̽��ֱ��technology is being commercialised by Cambridge Enterprise, the ̽��ֱ��’s commercialisation arm.

A low-cost, high-speed method for printing electronics using graphene and other conductive materials could open up a wide range of commercial applications.

Being able to produce conductive inks that could effortlessly be used for printing at a commercial scale at a very high speed will open up all kinds of different applications for graphene and other similar materials

Tawfique Hasan

Roll-to-roll printing of graphene ink

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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