Search Results

Rice University engineers have achieved a new benchmark in the design of atomically thin solar cells made of semiconducting perovskites, boosting their efficiency while retaining their ability to stand up to the environment. The lab of Aditya Mohite of Rice’s George R. Brown School of Engineering discovered that sunlight itself contracts the space between atomic layers in 2D perovskites enough to improve the material’s photovoltaic efficiency by up to 18%, an astounding leap in a field where progress is often measured in fractions of a percent. The research "Light-activated interlayer contraction in two-dimensional perovskites for high-efficiency solar cells" appears in Nature Nanotechnology. “In 10 years, the efficiencies of perovskites have skyrocketed from about 3% to over 25%,” Mohite said. “Other semiconductors have taken about 60 years to get there. That’s why we’re so excited.” Perovskites are compounds that have cubelike crystal lattices and are highly efficient light harvesters. Their potential has been known for years, but they present a conundrum: They’re good at converting sunlight into energy, but sunlight and moisture degrade them. “A solar cell technology is expected to work for 20 to 25 years,” said Mohite, an associate professor of chemical and biomolecular engineering and of materials science and nanoengineering. “We’ve been working for many years and continue to work with bulk perovskites that are very efficient but not as stable. In contrast, 2D perovskites have tremendous stability but are not efficient enough to put on a roof. “The big issue has been to make them efficient without compromising the stability,” he said. The Rice engineers and their collaborators at Purdue and Northwestern universities, U.S. Department of Energy national laboratories Los Alamos, Argonne and Brookhaven, and the Institute of Electronics and Digital Technologies (INSA) in Rennes, France, discovered that in certain 2D perovskites, sunlight effectively shrinks the space between the atoms, improving their ability to carry a current. “We find that as you light the material, you kind of squeeze it like a sponge and bring the layers together to enhance the charge transport in that direction,” Mohite said. The researchers found placing a layer of organic cations between the iodide on top and lead on the bottom enhanced interactions between the layers. “This work has significant implications for studying excited states and quasiparticles in which a positive charge lies on one layer and the negative charge lies on the other and they can talk to each other,” Mohite said. “These are called excitons, which may have unique properties. “This effect has given us the opportunity to understand and tailor these fundamental light-matter interactions without creating complex heterostructures like stacked 2D transition metal dichalcogenides,” he said. Experiments were confirmed by computer models by colleagues in France. “This study offered a unique opportunity to combine state of the art ab initio simulation techniques, material investigations using large scale national synchrotron facilities and in-situ characterizations of solar cells under operation,” said Jacky Even, a professor of physics at INSA. “The paper depicts for the first time how a percolation phenomenon suddenly releases the charge current flow in a perovskite material.” Both results showed that after 10 minutes under a solar simulator at one-sun intensity, the 2D perovskites contracted by 0.4% along their length and about 1% top to bottom. They demonstrated the effect can be seen in 1 minute under five-sun intensity. “It doesn’t sound like a lot, but this 1% contraction in the lattice spacing induces a large enhancement of electron flow,” said Rice Applied Physics graduate student and co-lead author Wenbin Li. “Our research shows a threefold increase in the electron conduction of the material.” At the same time, the nature of the lattice made the material less prone to degrading, even when heated to 80 degrees Celsius (176 degrees Fahrenheit). The researchers also found the lattice quickly relaxed back to its normal configuration once the light was turned off. “One of the major attractions of 2D perovskites was they usually have organic atoms that act as barriers to humidity, are thermally stable, and solve ion migration problems,” said graduate student and co-lead author Siraj Sidhik. “3D perovskites are prone to heat and light instability, so researchers started putting 2D layers on top of bulk perovskites to see if they could get the best of both. “We thought, let’s just move to 2D only and make it efficient,” he said. To observe the material contraction in action, the team made use of two U.S. Department of Energy (DOE) Office of Science user facilities: the National Synchrotron Light Source II at DOE’s Brookhaven National Laboratory and the Advanced Photon Source (APS) at DOE’s Argonne National Laboratory. Argonne physicist Joe Strzalka, a co-author on the paper, used the ultrabright X-rays of the APS to capture minuscule structural changes in real-time the material in real time. The sensitive instruments at beamline 8-ID-E of the APS allow for “operando” studies, meaning those conducted while the device is undergoing controlled changes in temperature or environment under normal operating conditions. In this case, Strzalka and his colleagues exposed the photoactive material from the solar cell to simulated sunlight while keeping the temperature constant, and observed tiny contractions at the atomic level. As a control experiment, Strzalka and his co-authors also kept the room dark and raised the temperature, observing the opposite effect, an expansion of the material. This showed that it was the light itself, not the heat it generated, that caused the transformation. “For changes like this, it’s important to do operando studies,” Strzalka said. “The same way your mechanic wants to run your engine to see what’s happening inside it, we want to essentially take a video of this transformation instead of a single snapshot. Facilities such as the APS allow us to do that.” Strzalka noted the APS is in the midst of a major upgrade that will increase the brightness of its X-rays by up to 500 times. When it’s complete, he said, the brighter beams and faster, sharper detectors will improve scientists’ ability to spot these changes with even more sensitivity. That could help the Rice team tweak the materials for even better performance. “We’re on a path to get greater than 20% efficiency by engineering the cations and interfaces,” Sidhik said. “It would change everything in the field of perovskites because then people would begin to use 2D perovskites for 2D perovskite/silicon and 2D/3D perovskite tandems, which could enable efficiencies approaching 30%. That would make it compelling for commercialization.” For more information, visit: https://news.rice.edu/news/2021/ultrathin-solar-cells-get-boost

A high-performance version of the zinc-ion battery will enable station energy storage that promises to be cheaper, safer, and more environmentally friendly than lithium-ion batteries. Until now, zinc-ion batteries have been severely hampered by their rapid degradation during use. Now, a KAUST team has developed a new electrolyte and electrode combination that improved several aspects of zinc-ion battery performance, particularly the stability over multiple charges and discharge cycles. Their work was published in Energy & Environmental Science journal " Concentrated dual-cation electrolyte strategy for aqueous zinc-ion batteries" Stationary banks of batteries connected to renewable energy sources, such as solar installations or wind farms, could be key to the transition from the current fossil-fuel-powered electricity grid. Unlike batteries for mobile applications, such as laptops or electric cars where battery size and weight are key, stationary batteries can be relatively large and heavy, raising the possibility that alternative rechargeable battery technologies to lithium-ion could be deployed. Batteries centered on a water-based solution of zinc ions have shown great potential for stationary storage in terms of their high capacity, low cost, and lack of toxicity. “But issues including low cycling stability and fast self-discharge have prohibited practical applications of aqueous zinc-ion batteries,” says Yunpei Zhu, a research scientist in Husam Alshareef's group, who led the work. “Both of these issues are related to the design of electrolytes and electrode materials,” he adds. The water-based electrolyte caused problems at both electrodes of the battery, causing damaging side reactions at the anode and rapid dissolution of the cathode. To combat these issues, the team developed a water-electrolyte with a very high salt concentration. The more salt ions present in the solution to bind surrounding water molecules, the fewer free water molecules are available to damage the electrodes. As zinc salts typically show limited solubility in water, the team added sodium to produce a highly concentrated electrolyte of zinc perchlorate and sodium perchlorate. “We found this combination delivers very high solubility to suppress water activity, without lowering the key attributes of zinc-ion batteries, including their high ionic conductivity, safety or environmental friendliness,” Zhu says. In addition to the novel electrolyte, the team developed a new nanofiber-based cathode material for batteries. “The nanofiber morphology enhances ion diffusion, which ensures faster charge and discharge rates of the aqueous Zn-ion batteries,” Alshareef says. In testing, the team saw almost no capacity decay over 2,000 charge cycles. “This combination of electrode and electrolyte potentially solves the shortcomings of conventional aqueous Zn-ion batteries,” Alshareef says. For more information, visit: https://discovery.kaust.edu.sa/en/article/1156/electric-gains-in-battery-performance

Speaker: Ian Tevis | Company: SAFI-Tech | Date: 11-12 May 2021 | Full Presentation Join TechBlick on an annual pass to join all live online conference or online version of onsite conference access library of on-demand talks (600 talks + PDFs) portfolio of expert led masterclass year-round platform https://www.techblick.com/ And do NOT miss our flagship event in Berlin on 17-18 OCT 2023 focused on Reshaping the Future of Electronics. This event attracts 550-600 participants from all the world and offers a superb ambience and dynamic exhibition floor. To learn more visit https://www.techblick.com/electronicsreshaped To see feedback about previous event see https://www.techblick.com/events-agenda

Displays & Lighting: Innovations & Market Trends 14 Jul, 14:00 – 16 Jul, 22:00 Virtual Event Platform Topics Covered: Market Data & Forecasts • microLED/OLEDs • AI in Displays • Flexible/Rollable Displays • Printed Displays • AR/VR Glasses • Quantum Dots & Phosphors • TADF • Nanoimprint • R2R Displays • Outdoor Displays • Automotive Display • Reflective Add the event date to your Calendar: Google Calendar | Microsoft Outlook Calendar | Office 365 Calendar | Yahoo Calendar Speakers include: And many more... Meet Exhibitors During the LIVE event Add our 14 July-16 July event to your Calendar: Google Calendar | Microsoft Outlook Calendar | Office 365 Calendar | Yahoo Calendar Past attendees have said: Read more customer feedback Our upcoming LIVE online events: With a single annual pass, you can watch full speaker video presentations of TechBlick's past events on-demand

Imagine your car starting the moment you get in because it recognizes the jacket you’re wearing. Consider the value of a hospital gown that continuously measures and transmits a patient’s vital signs. These are just two applications made possible by a new “body area network”-enabling fabric invented by engineers at the University of California, Irvine. In a paper published recently in Nature Electronics "Textile-integrated metamaterials for near-field multibody area networks", researchers in UCI’s Henry Samueli School of Engineering detail how they integrated advanced metamaterials into flexible textiles to create a system capable of battery-free communication between articles of clothing and nearby devices. “If you’ve held your smartphone or charge card close to a reader to pay for a purchase, you have taken advantage of near-field signaling technologies. Our fabrics work on the same principle, but we’ve extended the range significantly,” said co-author Peter Tseng, UCI assistant professor of electrical engineering & computer science. “This means you could potentially keep your phone in your pocket, and just by brushing your body against other textiles or readers, power and information can be transferred to and from your device.” Lead author Amirhossein Hajiaghajani, a UCI Ph.D. student in electrical engineering & computer science, said the invention enables wearers to digitally interact with nearby electronic devices and make secure payments with a single touch or swipe of a sleeve. “With our fabric, electronics establish signaling as soon as you hover your clothes over a wireless reader, so you can share information with a simple high-five or handshake,” he said. “You would no longer need to manually unlock your car with a key or separate wireless device, and your body would become the badge to open facility gates.” Tseng likens the technology to a railway that transmits power and signals as it crisscrosses a garment. The system allows new segments to be added readily, and separate pieces of clothing can be paired to “talk” with one another. The near-field communications protocol has enabled the growth in applications such as wireless device charging and powering of battery-free sensors, but a drawback of NFC has been its limited range of only a couple of inches. The UCI researchers extended the signal reach to more than 4 feet using passive magnetic metamaterials based on etched foils of copper and aluminum. The team’s innovation was designed to be highly flexible and tolerant of bodily motion. Because signals travel in the UCI-invented system via magnetic induction – versus the continuous hard-wire connections that had been state-of-the-art in smart fabrics – it’s possible to coordinate separate pieces of clothing. In athletic gear, pants can measure leg movements while communicating with tops that track heart rate and other stats. The applications in medicine are countless, Hajiaghajani said, such as freeing hospital staff from the task of applying numerous patient sensors, as they can all be integrated into metamaterial-equipped gowns. The materials involved in the system are low-cost and easy to fabricate and customize, he noted, and varying lengths and branches of the metamaterial “rails” can be heat-pressed onto wearers’ existing clothing – no need to go out and buy a brand-new high-tech tracksuit. “Our textiles are simple to make and can be integrated with interesting wearable designs,” Hajiaghajani said. “We want to create designs that not only are cool and inexpensive but can reduce the burden that modern electronics can bring to our lives.” For more information, visit: https://news.uci.edu/2021/11/16/uci-invention-lets-people-pay-for-purchases-with-a-high-five/

Epishine and Optiqo have collaborated and this has now resulted in a brand-new version of Optiqo's QlvrBox powered with organic solar cells optimized to harvest indoor lighting that now is available for order worldwide. This version of the QlvrBox enables improved sustainability, monitoring, and quality management of cleaning and facility management services. Optiqo's QlvrBox uses real-time visitor traffic data to alert maintenance technicians when facility areas require service or cleaning, which enables companies to proactively manage and validate cleaning and maintenance events to ensure 100% compliance and, in turn, increase customer satisfaction. The QlvrBox also has an indicator showing the most recent service or cleaning event to ensure the facility’s visitors feel secure. Epishine and Optiqo have cooperated to optimize Optiqo's QlvrBox. QlvrBox currently operates on batteries, enabling the device to be installed independently of the facility’s infrastructure. This feature offers a great benefit when installing the boxes, however, the batteries need to be replaced every 1-3 years. The new version of QlvrBox is developed with Epishine's solution for light energy harvesting, which extends the battery life by the generated power from ambient lighting. This reduces both the number of batteries and the maintenance cost. For more information, visit: https://www.epishine.com/pr/worldwide-launch-of-optiqos-qlvrbox-extended-with-epishines-organic-solar-cells-optimised-to-harvest-indoor-lighting ‍

Nano Ops, Inc. is pleased to host its first webinar on December 2, 2021, @ 1:30 eastern since the launch of FLEX RD and FFx RD800, Fab-in-a-Tool series products. Nano OPS is the world's first manufacturer of purely additive manufacturing tools capable of printing nanoscale features, bringing a nanomanufacturing fab in your lab. The webinar with Dr. Ahmed Busnaina, CTO of Nano OPS, Inc. will discuss an elegant, low-cost, high throughput additive manufacturing technology that can be implemented at a fraction of the capital investment required of any other technology. Join the Q&A to ask all your questions on how you can implement manufacturing solutions for advanced packaging in your organization at a fraction of the cost of conventional technologies or foundry offered services using additive manufacturing of electronics. Register Here https://us02web.zoom.us/webinar/register/8316377774487/WN_xPhegbzSTJC8SpfrOMqaAQ

Speaker: Jurgen van Peer | Company: Nanogate | Date: 11-12 May 2021 | Full Presentation Digital printing has clearly established itself for graphics printing, thanks to the advantages it offers over traditional processes like screen printing. More recently, digital printing started morphing into digital manufacturing and also Printed Electronics is taking advantage of that evolution. In this talk we will review Agfa's digital conductive inks based on nanomaterials, and highlight some features of newly developed inks. In the second part of the talk, Nanogate Netherlands will discuss the application of additive digital manufacturing in motor sport products. Join TechBlick on an annual pass to join all live online conference or online version of onsite conference access library of on-demand talks (600 talks + PDFs) portfolio of expert led masterclass year-round platform https://www.techblick.com/ And do NOT miss our flagship event in Berlin on 17-18 OCT 2023 focused on Reshaping the Future of Electronics. This event attracts 550-600 participants from all the world and offers a superb ambience and dynamic exhibition floor. To learn more visit https://www.techblick.com/electronicsreshaped To see feedback about previous event see https://www.techblick.com/events-agenda

A team of engineers at the University of South Florida has invented a new technology that could forever change the manufacturing of wearable, electronic sensors. They’ve figured out a way to speed up production without having to use polymer binders – the industry standard in printing flexible sensors, which are often used to monitor vital signs in health care settings. Their technology "Corona-Enabled Electrostatic Printing for Ultra-Fast R2R Manufacturing of Binder-Free Multifunctional E-Skins", featured on the cover of the journal ACS Applied Materials & Interfaces, prints electronic skin, or “e-skin,” by using corona discharge to create a strong electric field between binder-free functional powders, such as graphene, and flexible, non-conductive surfaces, such as medical tape. The electrostatic force used in Corona-Enabled Electrostatic Printing enables a multitude of e-skin sensors to be printed within sub-seconds, compared to the 20 minutes it takes with polymer binders and doesn’t require heat. E-skin is a micrometer-thin, pliable technology that can be used to measure things such as strain, temperature, and sound. Ying Zhong, assistant professor of mechanical engineering at USF, and her collaborator, Long Wang at California Polytechnic State University, found that the printing technique has broad applications, such as in health monitoring, prosthetics, and robotics. Unlike with polymer binders, there aren’t sizing limitations, making the technique a strong candidate for the roll-to-roll manufacturing of large flexible sensors, which can greatly reduce production costs. “As a new, advanced manufacturing strategy, Corona-Enabled Electrostatic Printing will potentially transform the cost structure for large-area and high-performance electronics and enable versatile applications of flexible, functional systems,” Zhong said. “The technique can help contribute to maintaining the U.S.’s leadership in advanced manufacturing.” Zhong recently received a $308,928 grant from the National Science Foundation to advance her research, proving the patent-pending ultra-fast manufacturing technique can be used to print materials beyond multifunctional e-skin. For more information: https://www.usf.edu/news/2021/usf-engineers-invent-ultra-fast-manufacturing-technology.aspx

In 2017, Green Bay Packers quarterback Aaron Rodgers broke his right collarbone in a game against the Minnesota Vikings. Typically, it takes about 12 weeks for a collarbone to fully heal, but by mid-December fans and commentators were hoping the three-time MVP might recover early and save a losing season. So did Xudong Wang, a professor of materials science and engineering at the University of Wisconsin–Madison and an expert in creating thin, movement-powered medical devices. “I started wondering if we could provide a new solution to bring athletes back to the field quicker than ever,” Wang says. The researchers published the paper " An implantable and bioresorbable electrostimulation device with its own power supply for the healing of bone fractures with biofeedback" in PNAS. Researchers know that electricity can help speed up bone healing, but “zapping” fractures has never really caught on since it requires surgically implanting and removing electrodes powered by an external source. A major update of that same electrostimulation concept, Wang’s latest invention didn’t come in time to help the 2017 Packers — however, it may help many others by making electrostimulation a much more convenient option to speed up bone healing. His thin, flexible device is self-powered, implantable, and bioresorbable, so once the bone is knitted back together, the device’s components dissolve within the body. Bone is a piezoelectric material, meaning it produces a tiny bit of electricity when placed under strain. These jolts of electricity stimulate factors that promote bone growth and healing, which is why electrostimulation is an effective therapy. While there are external stimulators that create an electric field to accelerate healing indirectly, the ideal solution is stimulating the bone directly. Putting the device inside the body, however, has unique requirements — not the least of which is powering it, according to Wang. “The ideal case is to have the device be self-generating, which was something that didn’t exist before this,” he says. To create the new fracture electrostimulation device, or FED, Wang and his team started with a triboelectric nanogenerator, a thin-film device with microstructured surfaces that converts mechanical energy produced by tiny movements into electric power. They coupled the nanogenerator with a pair of electrodes to distribute the electric field to the bone. They built these ultrathin, biodegradable, and bioresorbable components on a substrate of poly(lactic-co-glycolic acid), a commonly used FDA-approved biocompatible polymer. The researchers’ initial tests confirmed that small movements of the device did indeed create an electrical stimulation of about 4 volts, which it could sustain for over six weeks. They then tested the device on rats. The animals implanted with the device completely recovered from a tibia fracture in about six weeks, much more quickly than animals in a control group. The mineral density and flexural strength of the healed bones also reached the same level as healthy bones in the animals that received the electrostimulation. After the treatment, the devices degraded and absorbed into the rats’ bodies with no complications and no need for surgical removal. Wang says that it’s possible to fine-tune how long the stimulator will last within the body — from weeks to months — by tweaking the properties of the bioresorbable material coating the device. Eventually, Wang would like to scale up the fracture electrostimulation device so it will work in humans. But for these self-powered devices, the energy source can be a factor. “Typically, when someone has a broken bone, they need to restrict their movement,” he explains. In other words, someone wearing a cast might not produce enough mechanical energy to power the triboelectric nanogenerator. “The way a rat move provides constant stimulation for the device, but for a broken bone in a human that can’t be moved, that’s an issue,” says Wang. However, the human body provides virtually endless sources of movement that could power the fracture electrostimulation device if the broken bone must remain immobile. “We may need the device to respond to other types of internal mechanical sources, like blood pressure changes,” says Wang, who’s already looking to the FED’s future. “It will be very interesting and impactful to address the development from animal to human,” he says. For more information, visit: https://news.wisc.edu/self-powered-implantable-device-stimulates-fast-bone-healing-then-disappears-without-a-trace/

World-class Agenda | Latest Technology Updates | Exclusive Networking Sessions Topics Covered | Perovskites | Organics | CIGS | Tandem | R2R | Inkjet | Printed | Thin Film Deposition Scale-Up | Stability | Thin Film Barriers | Material Innovations | Substrates. 1-2 December 2021 | 1pm - 9pm CET Add to your Calendar iCalendar (majority of email clients) Google Calendar | Microsoft Outlook Calendar | Office 365 Calendar | Yahoo Calendar TechBlick's sixth Live event on 1 -2 December 2021 will cover The Future of Photovoltaics and as always we have a superb speaker line-up, interactive exhibitor booths for you to visit and exclusive networking sessions. TechBlick is a year round event series with over 350+ Analyst picked live online presentations on emerging technologies. With a single Annual Pass you have year long access to our platform where you can join live conferences as well as watch over 250 (and growing) on-demand presentations and participate in Masterclasses by leading industry exerts. You can also network with fellow attendees as well as learn from, and meet our exhibitors. TechBlick will once again be hosting the popular networking sessions in our exclusive lounge. This will be your chance to mix with attendees and meet speakers just as you would at a physical event. If you are not familiar with the lounge, you can try it out here. Why don't you grab a drink and join us for this sociable occasion. Leading Global Speakers Include: Annual Pass With an Annual Pass you can participate in all our upcoming LIVE (online) events, engage with our library of on-demand content, and learn from our industry-led masterclasses. To become an annual member of TechBlick sign up here until 12 November 2021 to save €100, making the pass just €500 per year (apply code Save100Euros at check-out). Alternatively, you can also set up a monthly payment of €50 per month with a minimum contract period of 6 months. To do this, email chris@TechBlick.com Do not take our word for it - read what our members say: Meet and network with over 70 exhibitors Enjoy Your Opportunity to Connect, Learn & Engage With The Emerging Technology Community For a Whole Year

Some people are born with hearing loss, while others acquire it with age, infections, or long-term noise exposures. In many instances, the tiny hairs in the inner ear’s cochlea that allow the brain to recognize electrical pulses as sound are damaged. As a step toward an advanced artificial cochlea, researchers in ACS Nano report a conductive membrane, which translated sound waves into matching electrical signals when implanted inside a model ear, without requiring external power. The paper "Acoustic Core-Shell Resonance Harvester for Application of Artificial Cochlea Based on the Piezo-Triboelectric Effect" is published in ACS NANO. When the hair cells inside the inner ear stop working, there’s no way to reverse the damage. Currently, treatment is limited to hearing aids or cochlear implants. But these devices require external power sources and can have difficulty amplifying speech correctly so that it’s understood by the user. One possible solution is to simulate healthy cochlear hairs, converting noise into the electrical signals processed by the brain as recognizable sounds. To accomplish this, previous researchers have tried self-powered piezoelectric materials, which become charged when they’re compressed by the pressure that accompanies sound waves, and triboelectric materials, which produce friction and static electricity when moved by these waves. However, the devices aren’t easy to make and don’t produce enough signals across the frequencies involved in human speech. So, Yunming Wang and colleagues wanted a simple way to fabricate a material that used both compression and friction for an acoustic sensing device with high efficiency and sensitivity across a broad range of audio frequencies. To create a piezo-triboelectric material, the researchers mixed barium titanate nanoparticles coated with silicon dioxide into a conductive polymer, which they dried into a thin, flexible film. Next, they removed the silicon dioxide shells with an alkaline solution. This step left behind a sponge-like membrane with spaces around the nanoparticles, allowing them to jostle around when hit by sound waves. In tests, the researchers showed that contact between the nanoparticles and polymer increased the membrane’s electrical output by 55% compared to the pristine polymer. When they sandwiched the membrane between two thin metal grids, the acoustic sensing device produced a maximum electrical signal at 170 hertz, a frequency within the range of most adults’ voices. Finally, the researchers implanted the device inside a model ear and played a music file. They recorded the electrical output and converted it into a new audio file, which displayed a strong similarity to the original version. The researchers say their self-powered device is sensitive to the wide acoustic range needed to hear most sounds and voices. For more information, visit: https://www.acs.org/content/acs/en/pressroom/presspacs/2021/acs-presspac-october-27-2021/flexible-device-could-treat-hearing-loss-without-batteries.html