Posts belonging to Category electronics



Super-Efficient Production Of Hydrogen From Solar Energy

Hydrogen is an alternative source of energy that can be produced from renewable sources of sunlight and water. A group of Japanese researchers has developed a photocatalyst that increases hydrogen production tenfold.

When light is applied to photocatalysts, electrons and holes are produced on the surface of the catalyst, and hydrogen is obtained when these electrons reduce the hydrogen ions in water. However, in traditional photocatalysts the holes that are produced at the same time as the electrons mostly recombine on the surface of the catalyst and disappear, making it difficult to increase conversion efficiency.

Professor Tachikawa’s research group from the Kobe University developed a photocatalyst made of mesocrystal, deliberately creating a lack of uniformity in size and arrangement of the crystals. This new photocatalyst is able to spatially separate the electrons and electron holes to prevent them recombining. As a result, it has a far more efficient conversion rate for producing hydrogen than conventional nanoparticulate photocatalysts (approximately 7%).

The team developed a new method called “Topotactic Epitaxial Growth” that uses the nanometer-sized spaces in mesocrystals.
Using these findings, the research group plans to apply mesocrystal technology to realizing the super-efficient production of hydrogen from solar energy. The perovskite metal oxides, including strontium titanate, the target of this study, are the fundamental materials of electronic elements, so their results could be applied to a wide range of fields.

The discovery was made by a joint research team led by Associate Professor Tachikawa Takashi (Molecular Photoscience Research Center, Kobe University) and Professor Majima Tetsuro (Institute of Scientific and Industrial Research, Osaka University). Their findings were published  in the online version of Angewandte Chemie International Edition.

Source: http://www.kobe-u.ac.jp/

Self-Healing Lithium-Ion Batteries

Researchers at the University of Illinois have found a way to apply self-healing technology to lithium-ion batteries to make them more reliable and last longer.

The group developed a battery that uses a silicon nanoparticle composite material on the negatively charged side of the battery and a novel way to hold the composite together – a known problem with batteries that contain silicon.

Materials science and engineering professor Nancy Sottos and aerospace engineering professor Scott White led the study published in the journal Advanced Energy Materials.

“This work is particularly new to self-healing materials research because it is applied to materials that store energy,” White said. “It’s a different type of objective altogether. Instead of recovering structural performance, we’re healing the ability to store energy.”

The negatively charged electrode, or anode, inside the lithium-ion batteries that power our portable devices and electric cars are typically made of a graphite particle composite. These batteries work well, but it takes a long time for them to power up, and over time, the charge does not last as long as it did when the batteries were new.

Silicon has such a high capacity, and with that high capacity, you get more energy out of your battery, except it also undergoes a huge volume expansion as it cycles and self-pulverizes,” Sottos explained.

Past research found that battery anodes made from nanosized silicon particles are less likely to break down, but suffer from other problems.

You go through the charge-discharge cycle once, twice, three times, and eventually you lose capacity because the silicon particles start to break away from the binder,” White said.

To combat this problem, the group further refined the silicon anode by giving it the ability to fix itself on the fly. This self-healing happens through a reversible chemical bond at the interface between the silicon nanoparticles and polymer binder.

Source: https://news.illinois.edu/

Dissolvable Metal Supports for 3D Printing

Support for a visiting professor plus an off-the-cuff remark have led an Arizona State University (ASU) researcher to develop what could be the Holy Grail solution to speeding up the end-to-end process of metal 3D printing.

Owen Hildreth, ASU assistant professor of 3D Nanofabrication, was developing new approaches to reactive silver ink production when he thought he’d sit in on talks regarding the soon-to-be-opened ASU Polytechnic Manufacturing Research and Innovation Hub. One of the speakers, Timothy Simpson, was describing the practical challenges of setting up an additive manufacturing (AM) lab.

Combining a mechanical engineering degree (applied to five years’ work in the 2D printing industry) with a Ph.D. in nanofabrication materials engineering, Hildreth just may have been in the perfect position to bring a fresh perspective to the metal support problem. In contrast to the use of mechanical tools such as wire-EDM equipment, his concept would cause certain areas of a metal AM part to react chemically when immersed in a corrosive solution. The goal was to produce controlled degradation that would literally eat away the supports but leave the actual part virtually intact.

However, because multi-material 3D printing systems are not yet widely available, Hildreth also investigated ways to selectively remove the supports of powder-bed-type metal AM parts. Starting with a simple design for demonstration — a small 17-4 stainless steel cylinder 3D-printed with a single row of 100-micron-diameter needle-like supports — he tested two possible approaches.

In the first one, termed direct dissolution, the part was heat-treated (annealed) while packed with sodium ferrocyanide; this step precipitated out much of the protective chromium carbide, rendering the no-longer-stainless steel susceptible to chemical etching. The latter process was successful, but the part itself experienced significant etching, which continued the longer the part was allowed to sit in the solution.

Source: http://www.rapidreadytech.com/

How To Harness Heat To Power Computers

One of the biggest problems with computers, dating to the invention of the first one, has been finding ways to keep them cool so that they don’t overheat or shut down. Instead of combating the heat, two University of Nebraska–Lincoln engineers have embraced it as an alternative energy source that would allow computing at ultra-high temperatures. Sidy Ndao, assistant professor of mechanical and materials engineering, said his research group’s development of a nano-thermal-mechanical device, or thermal diode, came after flipping around the question of how to better cool computers.

thermal diode

If you think about it, whatever you do with electricity you should (also) be able to do with heat, because they are similar in many ways,” Ndao said. “In principle, they are both energy carriers. If you could control heat, you could use it to do computing and avoid the problem of overheating.”

A paper Ndao co-authored with Mahmoud Elzouka, a graduate student in mechanical and materials engineering, was published in the March edition of Scientific Reports. In it, they documented their device working in temperatures that approached 630 degrees Fahrenheit (332 degrees Celsius).

Source: http://news.unl.edu/

Clean Hydrogen Produced From Biomass

A team of scientists at the University of Cambridge has developed a way of using solar power to generate a fuel that is both sustainable and relatively cheap to produce. It’s using natural light to generate hydrogen from biomass. One of the challenges facing modern society is what it does with its waste products. As natural resources decline in abundance, using waste for energy is becoming more pressing for both governments and business. Biomass has been a source of heat and energy since the beginning of recorded history.  The planet’s oil reserves are derived from ancient biomass which has been subjected to high pressures and temperatures over millions of years. Lignocellulose is the main component of plant biomass and up to now its conversion into hydrogen has only been achieved through a gasification process which uses high temperatures to decompose it fully.

biomass can produce hydrogen

Lignocellulose is nature’s equivalent to armoured concrete. It consists of strong, highly crystalline cellulose fibres, that are interwoven with lignin and hemicellulose which act as a glue. This rigid structure has evolved to give plants and trees mechanical stability and protect them from degradation, and makes chemical utilisation of lignocellulose so challenging,” says  Dr Moritz Kuehnel, from the Department of Chemistry at the University of Cambridge and co-author of the research.

The new technology relies on a simple photocatalytic conversion process. Catalytic nanoparticles are added to alkaline water in which the biomass is suspended. This is then placed in front of a light in the lab which mimics solar light. The solution is ideal for absorbing this light and converting the biomass into gaseous hydrogen which can then be collected from the headspace. The hydrogen is free of fuel-cell inhibitors, such as carbon monoxide, which allows it to be used for power.

The findings have been  published in Nature Energy.

Source: http://www.cam.ac.uk/

Spintronics

A team of scientists led by Associate Professor Yang Hyunsoo from the National University of Singapore’s (NUS) Faculty of Engineering has invented a novel ultra-thin multilayer film which could harness the properties of tiny magnetic whirls, known as skyrmions, as information carriers for storing and processing data (nanocomputer) on magnetic media. The nano-sized thin film, which was developed in collaboration with researchers from Brookhaven National Laboratory, Stony Brook University, and Louisiana State University, is a critical step towards the design of data storage devices that use less power and work faster than existing memory technologies.

The digital transformation has resulted in ever-increasing demands for better processing and storing of large amounts of data, as well as improvements in hard drive technology. Since their discovery in magnetic materials in 2009, skyrmions, which are tiny swirling magnetic textures only a few nanometres in size, have been extensively studied as possible information carriers in next-generation data storage and logic devices.

Skyrmions have been shown to exist in layered systems, with a heavy metal placed beneath a ferromagnetic material. Due to the interaction between the different materials, an interfacial symmetry breaking interaction, known as the Dzyaloshinskii-Moriya interaction (DMI), is formed, and this helps to stabilise a skyrmion. However, without an out-of-plane magnetic field present, the stability of the skyrmion is compromised. In addition, due to its tiny size, it is difficult to image the nano-sized materials. The NUS team found that a large DMI could be maintained in multilayer films composed of cobalt and palladium, and this is large enough to stabilise skyrmion spin textures.

skyrmionsThis experiment not only demonstrates the usefulness of L-TEM in studying these systems, but also opens up a completely new material in which skyrmions can be created. Without the need for a biasing field, the design and implementation of skyrmion based devices are significantly simplified. The small size of the skyrmions, combined with the incredible stability generated here, could be potentially useful for the design of next-generation spintronic devices that are energy efficient and can outperform current memory technologies,” explains Professor Yang .

The invention was reported in the journal Nature Communications.

Source: http://news.nus.edu.sg

Artificial Intelligence Tracks In Real Time Everybody In The Crowd

Artificial Intelligence that can pick you out in a crowd and then track your every move. Japanese firm Hitachi‘s new imaging system locks on to at least 100 different characteristics of an individual … including gender, age, hair style, clothes, and mannerisms. Hitachi says it provides real-time tracking and monitoring of crowded areas.

Person of interestCLICK ON THE IMAGE TO ENJOY THE VIDEO

Until now, we need a lot of security guards and people to review security camera footage. We developed this AI software in the hopes it would help them do just that,” says Tomokazu Murakami, Hitachi researcher.

The system can help spot a suspicious individual or find a missing child, the makers say. So, an eyewitness could provide a limited description, with the AI software quickly scanning its database for a match.
In Japan, the demand for such technology is increasing because of the Tokyo 2020 Olympics, but for us we’re developing it in a way so that it can be utilized in many different places such as train stations, stadiums, and even shopping malls,” comments Tomokazu Murakami.

High-speed tracking of individuals such as this will undoubtedly have its critics. But as Japan prepares to host the 2020 Olympics, Hitachi insists its system can contribute to public safety and security.

Source: http://uk.reuters.com/

Ultrafast Flexible Electronic Memory

Engineering experts from the University of Exeter (UK) have developed innovative new memory using a hybrid of graphene oxide and titanium oxide. Their devices are low cost and eco-friendly to produce, are also perfectly suited for use in flexible electronic devices such as ‘bendablemobile phone, computer and television screens, and even ‘intelligentclothing.
. Crucially, these devices may also have the potential to offer a cheaper and more adaptable alternative to ‘flash memory’, which is currently used in many common devices such as memory cards, graphics cards and USB computer drives. The research team insist that these innovative new devices have the potential to revolutionise not only how data is stored, but also take flexible electronics to a new age in terms of speed, efficiency and power.

bendable mobile phone

Using graphene oxide to produce memory devices has been reported before, but they were typically very large, slow, and aimed at the ‘cheap and cheerful’ end of the electronics goods market”, said Professor David Wright, an Electronic Engineering expert from the University of Exeter.

Our hybrid graphene oxide-titanium oxide memory is, in contrast, just 50 nanometres long and 8 nanometres thick and can be written to and read from in less than five nanoseconds – with one nanometre being one billionth of a metre and one nanosecond a billionth of a second.”

The research is published in the scientific journal ACS Nano.

Source: http://www.exeter.ac.uk/

Graphene And Fractals Boost The Solar Power Storage By 3000%

Inspired by an American fern, researchers have developed a groundbreaking prototype that could be the answer to the storage challenge still holding solar back as a total energy solution. The new type of electrode created by RMIT University (Australia) researchers could boost the capacity of existing integrable storage technologies by 3000 per cent. But the graphene-based prototype also opens a new path to the development of flexible thin film all-in-one solar capture and storage, bringing us one step closer to self-powering smart phones, laptops, cars and buildings. The new electrode is designed to work with supercapacitors, which can charge and discharge power much faster than conventional batteries. Supercapacitors have been combined with solar, but their wider use as a storage solution is restricted because of their limited capacity.

RMIT’s Professor Min Gu said the new design drew on nature’s own genius solution to the challenge of filling a space in the most efficient way possible – through intricate self-repeating patterns known as “fractals”.

The leaves of the western swordfern are densely crammed with veins, making them extremely efficient for storing energy and transporting water around the plant,” said Gu, Leader of the Laboratory of Artificial Intelligence Nanophotonics at RMIT.

mimicking fern

Our electrode is based on these fractal shapes – which are self-replicating, like the mini structures within snowflakes – and we’ve used this naturally-efficient design to improve solar energy storage at a nano level. “The immediate application is combining this electrode with supercapacitors, as our experiments have shown our prototype can radically increase their storage capacity30 times more than current capacity limits.   “Capacity-boosted supercapacitors would offer both long-term reliability and quick-burst energy release – for when someone wants to use solar energy on a cloudy day for example – making them ideal alternatives for solar power storage.”  Combined with supercapacitors, the fractal-enabled laser-reduced graphene electrodes can hold the stored charge for longer, with minimal leakage.

Source: https://www.rmit.edu.au/

Smart Printed Electronics

Researchers in AMBER, the materials science research centre hosted in Trinity College Dublin, have fabricated printed transistors consisting entirely of 2-dimensional nanomaterials for the first time. These 2D materials combine exciting electronic properties with the potential for low-cost production. This breakthrough could unlock the potential for applications such as food packaging that displays a digital countdown to warn you of spoiling, wine labels that alert you when your white wine is at its optimum temperature, or even a window pane that shows the day’s forecast

This discovery opens the path for industry, such as ICT and pharmaceutical, to cheaply print a host of electronic devices from solar cells to LEDs with applications from interactive smart food and drug labels to next-generation banknote security and e-passports.

printed transistor

Prof Jonathan Coleman, who is an investigator in AMBER and Trinity’s School of Physics, said, “In the future, printed devices will be incorporated into even the most mundane objects such as labels, posters and packaging.
Printed electronic circuitry (constructed from the devices we have created) will allow consumer products to gather, process, display and transmit information: for example, milk cartons could send messages to your phone warning that the milk is about to go out-of-date.

We believe that 2D nanomaterials can compete with the materials currently used for printed electronics. Compared to other materials employed in this field, our 2D nanomaterials have the capability to yield more cost effective and higher performance printed devices. However, while the last decade has underlined the potential of 2D materials for a range of electronic applications, only the first steps have been taken to demonstrate their worth in printed electronics. This publication is important because it shows that conducting, semiconducting and insulating 2D nanomaterials can be combined together in complex devices. We felt that it was critically important to focus on printing transistors as they are the electric switches at the heart of modern computing. We believe this work opens the way to print a whole host of devices solely from 2D nanosheets.”
Led by Prof Coleman, in collaboration with the groups of Prof Georg Duesberg (AMBER) and Prof. Laurens Siebbeles (TU Delft, Netherlands), the team used standard printing techniques to combine graphene nanosheets as the electrodes with two other nanomaterials, tungsten diselenide and boron nitride as the channel and separator (two important parts of a transistor) to form an all-printed, all-nanosheet, working transistor.

The AMBER team’s findings have been published today in the journal Science*.

Source: http://ambercentre.ie

‘Spray-On’ Memory for Paper, Fabric, Plastic

USB flash drives are already common accessories in offices and college campuses. But thanks to the rise in printable electronics, digital storage devices like these may soon be everywhere – including on our groceries, pill bottles and even clothingDuke University researchers have brought us closer to a future of low-cost, flexible electronics by creating a new “spray-on digital memory device using only an aerosol jet printer and nanoparticle inks. The device, which is analogous to a 4-bit flash drive, is the first fully-printed digital memory that would be suitable for practical use in simple electronics such as environmental sensors or RFID tags. And because it is jet-printed at relatively low temperatures, it could be used to build programmable electronic devices on bendable materials like paper, plastic or fabric.

PrintingMemory

Duke University researchers have developed a new “spray-on” digital memory (upper left) that could be used to build programmable electronics on flexible materials like paper, plastic or fabric. They used LEDS to demonstrate a simple application.

We have all of the parameters that would allow this to be used for a practical application, and we’ve even done our own little demonstration using LEDs,” said Duke graduate student Matthew Catenacci, who describes the device in a paper published online in the Journal of Electronic Materials. At the core of the new device, which is about the size of a postage stamp, is a new copper-nanowire-based printable material that is capable of storing digital information.

Memory is kind of an abstract thing, but essentially it is a series of ones and zeros which you can use to encode information,” said Benjamin Wiley, an associate professor of chemistry at Duke and an author on the paper.

Source: https://today.duke.edu/

Your browsing history may be up for sale soon

A US House committee is set to vote on whether to kill privacy rules that would prevent internet service providers (ISPs) from selling users’ web browsing histories and app usage histories to advertisers. Planned protections, proposed by the Federal Communications Commission (FCC) that would have forced ISPs to get people’s consent before hawking their data – are now at risk. Here’s why it matters.

Your web browsing patterns contain a treasure trove of data, including your health concerns, shopping habits and visits to porn sites. ISPs can find out where you bank, your political views and sexual orientation simply based on the websites you visit. The fact that you’re looking at a website at all can also reveal when you’re at home and when you’re not.

spy your dataIf you ask the ISPs, it’s about showing the user more relevant advertising. They argue that web browsing history and app usage should not count as “sensitiveinformation.
Not all ISPs want to abolish the privacy protections. A list of several smaller providers – including Monkeybrains.net, Cruzio Internet and Credo Mobile – have written to representatives to oppose the decision. “One of the cornerstones of our businesses is respecting the privacy of our customers,” they said.
How does this differ from the way Google and Facebook use our data?
It’s much harder to prevent ISPs from tracking your data. You can choose not to use Facebook or Google’s search engine, and there are lots of tools you can use to block their tracking on other parts of the web, for example EFF’s Privacy Badger.

Consumers are generally much more limited for choice of ISP, in some cases only having one option in a given geographical area. This means they can’t choose one of the ISPs pledging to protect user data.

Source: https://www.theguardian.com/