An international research group led by Jaana Vapaavuori of Aalto University in Finland has produced an extensive review of the opportunities of plant biomass, or lignocellulose, for optical applications, replacing less environmentally friendly but commonly used materials such as sand and plastics. As reported in Advanced Materials [Kaschuk et al. Adv. Mater. (2021) DOI: 10.1002/adma.202104473], the group showed how to produce solar cells and glass from biowaste as a viable substitute for unrenewable resources. The team summarized what is needed for producing and applying plant-based optically functional materials in new smart material applications. As Vapaavuori said, “We wanted to map out as comprehensively as possible how lignocellulose could replace the unrenewable resources found in widely used technology, like smart devices or solar cells”. Lignocellulose, which is composed of carbohydrate polymers such as cellulose and hemicellulose, and the aromatic polymer lignin, is present in nearly every plant. When such biomass is broken down into extremely small parts and then put back together, it can be used to develop totally new biocomposite materials such as particle panels and wood/plastic composites for construction. However, its characteristics such as transparency, reflectiveness, UV-light filtering, and structural colors mean the material can also be used in optical applications, as investigated in this study. The use of combinations of its properties could lead to th...

The demand for the Internet of Things (IoT) is on the rise throughout society. Now, Ricoh’s flexible energy harvesting device efficiently generates power indoors or in shaded areas as a stand-alone power source for the constant operation of a variety of sensors. In September, Ricoh will start sample shipments of these devices.
The flexible energy harvesting device, sized 41mm by 47mm, uses a unique power generation organic photovoltaic (OPV) material developed jointly in 2013 in an industry-academia collaboration with Kyushu University. The result is efficient power generation in a low-light environment, such as indoors (approximately 200 lx), and medium-light such as shaded outdoor areas (approximately 10,000 lx). In addition, the thin, lightweight, and bendable film can be mounted on IoT devices of various shapes.
These devices can be used as stand-alone power sources for mobile and portable wearable terminals, beacons, and is ideal for social infrastructure monitoring devices, such as ones installed in tunnels and under bridges. This will make it unnecessary to replace batteries in a wide variety of small consumer electronic devices, which is expected to improve convenience and contribute to the Sustainable Development Goal “Affordable and Clean Energy”. Since the release of solid-state dye-sensitized solar cells (DSSC) for indoor use in 2020, Ricoh aims to expand its product lineup as soon as possible by providing samples to IoT device manufacturers, service provi...

Science is now one step closer to bringing the glow-in-the-dark effect often used in signs and watches to a wider variety of applications without the need for rare metals. Applying a new strategy for combining carbon-based organic molecules, researchers at Kyushu University and the Okinawa Institute of Science and Technology (OIST), both in Japan, have dramatically improved the length and strength of the glow produced by the versatile materials. As reported in a paper in Nature Materials, these novel organic materials have the potential to be more easily formed into paints and fibers than their rare-metal-containing counterparts. The new work builds off the same research group’s discovery in 2017 of the world’s first organic system for producing the glow-in-the-dark effect at room temperature by melting together two metal-free molecules. Formally known as persistent luminescence, the glow-in-the-dark phenomenon is also often referred to as phosphorescence, though this term is also applied to another emission mechanism commonly found in organic materials. While commercial glow-in-the-dark materials based on inorganic compounds containing rare-earth metals already achieve excellent performance, their inorganic nature often limits how they can be processed. “Organic materials are more readily available than rare-metal-containing inorganic materials, and their solubility makes them easier to process,” explains Chihaya Adachi, professor and leader of the research at Kyushu Un...

Scientists at Pohang University of Science and Technology in South Korea (POSTECH) have developed a sweat-collecting patch based on how cactus spines attract water. The patch, which responds quickly to biochemicals in sweat and enables the continuous monitoring of changes in sweat biochemicals according to their changes in the wearer's blood, could help diabetes patients who have to repeatedly draw blood, and could also find uses in wearable devices for daily healthcare monitoring. Sweat sensors are expected to be an effective wearable device for future non-invasive healthcare monitoring. Being able to capture sweat secretions is useful for analyzing bioanalytes in the body without the be need to draw blood, but can hampered by irregular and low sweat secretion rates. However, in this new study, which was reported in the journal Advanced Materials [Son et al. Adv. Mater. (2021) DOI: 10.1002/adma.202102740], a patch was developed that can be attached to the skin and quickly collects sweat by mimicking the principle behind cactus spines. As cacti grow in dry environments, they have to transport water droplets that form on the tip of their spines to their base to help them survive. In this process, the water droplets move because of the difference in pressure acting on the inside and outside of the curved surface of the water droplet, a phenomenon called Laplace pressure. This principle was used to mimic the structure of the cactus spine with wedge-shaped wettability patterns...

Because of their high strength and lightweight, carbon-fiber-based composite materials are gradually replacing metals for advancing all kinds of products and applications, from airplanes to wind turbines to golf clubs. But there's a trade-off. Once damaged or compromised, the most commonly-used carbon fiber materials are nearly impossible to repair or recycle. In a paper published in the journal Carbon, a team of researchers describes a new type of carbon fiber reinforced material that is as strong and light as traditionally used materials but can be repeatedly healed with heat, reversing any fatigue damage. This also provides a way to break it down and recycle it when it reaches the end of its life.
"Developing fatigue-resistant composites is a major need in the manufacturing community," said co-lead author Aniruddh Vashisth, University of Washington assistant professor of mechanical engineering. "In this paper, we demonstrate a material where either traditional heat sources or radio frequency heating can be used to reverse and postpone its aging process indefinitely."
The material is part of a recently developed group known as carbon fiber reinforced vitrimer, named after the Latin word for glass, that shows a mix of solid and fluid properties. The materials typically used today, whether in sporting goods or aerospace, are carbon fiber reinforced polymers.
Traditional carbon fiber reinforced polymers typically fall into two categories: thermoset or thermoplastic. The...

Printed Electronics is everywhere and can be found in applications as diverse as a smart diaper to a precision missile. In this article, TechBlick will highlight some application and technology development cases for roll-to-roll (R2R) printed electronics. In doing so, TechBlick will take you on a journey spanning applications in healthcare, automotive, photovoltaics, displays, and beyond. The common thread here is R2R printing of electronics regardless of printing technique, e.g., screen, flexo, gravure, slot die, etc. The applications reviewed herein are presented randomly and follow no particular order of importance. The images and examples below are extracted from 2021 presentations given at TechBlick, which is the home of printed, flexible, hybrid, and in-mould electronics. TechBlick Individual Annual Pass or Group Access benefits for 12 months: Events: Participate in all interactive LIVE (online) TechBlick events Networking: Connect with the key players across the value chain from OEMs to material suppliers Train: Learn the ins and outs of technologies from our portfolio of expert-led masterclasses Market Assessment: Follow the latest market info and forecasts from leading market research analysts Information Portal: Access the on-demand library of state-of-the-art fresh presentations Discount: Major discount to participate in in-person physical events

Printed, Flexible, Hybrid, and/or R2R Electronics | Additively Manufactured Electronics | Electronic Packaging | Quantu...

Speaker: Mike Mastropietro | Company: ACI Materials | Date: 11-12 May 2021 | Full Presentation ACI will introduce to the world its Alchemy Conductive Inks. These high-performance printable conductors allow PTF ink like ease of use and processing with fired/sintered thick film electrical performance. The talk will describe some of the overall benefits of using these materials in manufacture of flexible and 3D printed electronics including: low volume resistivity and sheet resistance higher current carrying capacity lower cost per ohm square in use superior crease ability of narrow traces formulation latitude from viscous paste to sprayable Several examples will be presented including 3D circuit structures high resolution traces high power density busbars reflow solder ability 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...

The perovskite electronic shelf label (PESL) is the second product from Saule Technologies (Warsaw, Poland) using perovskite photovoltaic cells, the first being large-size cells designed for building façades. The new pioneering solution represents the IoT category – it is an intelligent system for operating electronic labels. Importantly, unlike traditional ESLs, it is powered not by a battery but by a perovskite photovoltaic cell. Electronic labels with their own practically inexhaustible power source, not requiring the costly and time-consuming battery replacement, are not only cheaper and more convenient to use than the traditional ESLs, but also offer energy efficiency and enable resigning from batteries that are very harmful to the environment. And this is an important step in the implementation of the sustainable development strategy. Using perovskite photovoltaic cells, PESLs are a breakthrough solution also in view of their unique capabilities to communicate with customers of retail stores. They significantly reduce product labeling time and ‒ most importantly ‒ allow real-time price verification. Perovskite photovoltaic cells from Saule Technologies, while being far more efficient than, for instance, the amorphous silicon photovoltaic cells used in calculators, display high efficiency also in artificial light. As they continue to work efficiently even when the rays of light fall at a big angle ‒ as is the case with pendant lamps ‒ they can supply power to produ...