Researchers have found a way to get electrons to travel much farther than was previously thought possible in materials for organic solar cells. This advance could make these solar cells much more useful than inorganic alternatives.
“For years, people had treated the poor conductivity of organics as an unavoidable fact, and this shows that that’s not always the case,” says research leader Stephen Forrest, professor of engineering at University of Michigan.
Peter Mascher
is a professor in the Department of Engineering Physics and holds the William Sinclair Chair in Optoelectronics at McMaster University in Ontario, Canada. There, he leads a research group specializing in the fabrication and characterization of nanostructures. Mascher was recently named technical editor of the ECS Journal of Solid State Science and Technology (JSS) in the area of dielectric science and materials.
The Electrochemical Society: What made you want to take on an ECS editorial role?
Peter Mascher: I’ve been a member of the ECS Dielectric Science and Technology Division for many years and we’ve had many discussion on how to raise the quality of submissions to JSS and by extension, the quality of the journal overall. At some point in time, when the opportunity arises, one should try to make a contribution rather than just discussing it. I think there are avenues toward increasing the profile of the journal and I hope I can make a contribution there.
ECS: What do you hope to accomplish in your new role as JSS technical editor?
PM: I would like my colleagues who contribute to the ECS meetings in the various symposia to be much more aware of the journal and the opportunity to publish in JSS, which will help increase the overall quality. There should be a strong connection between the excellent presentations that are given at the various symposia at ECS meetings and the manuscripts that are being submitted to the journal.
By: Neal Dawson-Elli, Seong Beom Lee, Manan Pathak, Kishalay Mitra, and Venkat R. Subramanian
This article refers to a recently published open access paper in the Journal of The Electrochemical Society, “Data Science Approaches for Electrochemical Engineers: An Introduction through Surrogate Model Development for Lithium-Ion Batteries.”
Image via Neal Dawson-Elli
(Click to enlarge.)
Data science is often hailed as the fourth paradigm of science. As the computing power available to researchers increases, data science techniques become more and more relevant to a larger group of scientists. A quick literature search for electrochemistry and data science will reveal a startling lack of analysis done on the data science side. This paper is an attempt to help introduce the topics of data science to electrochemists, as well as to analyze the power of these methods when combined with physics-based models.
At the core of the paper is the idea that one cannot be successful treating every problem as a black box and applying liberal use of data science – in other words, despite its growing popularity, it is not a panacea. The image shows the basic workflow for using data science techniques – the creation of a dataset, splitting into training-test pairs, training a model, and then evaluating the model on some task. In this case, the training data comes from many simulations of the pseudo two-dimensional lithium-ion battery model. However, in order to get the best results, one cannot simply pair the inputs and outputs and train a machine learning model on it. The inputs, or features, must be engineered to better highlight changes in your output data, and sometimes the problem needs to be totally restructured in order to be successful.
Image via Michael Geminder
Scientists have developed energy efficient, ultra-thin light-emitting diodes (LEDs) for next-generation communication technologies.
Light sources that reliably convert electrical to optical signals are of fundamental importance to information processing technologies. Energy-efficient and high-speed LEDs that can be integrated onto a microchip and transmit information are one of the key elements in enabling high volume data communication.
Two-dimensional (2D) semiconductors, graphene-like, atomically thin materials, have recently attracted significant interest due to their size (just a few atoms thick), well-defined light emission properties, and their prospects for on-chip integration. While, in recent years, researchers have succeeded in fabricating LEDs based on these materials, realizing efficient light emission has remained a challenge.
An efficient LED device converts most of its electrical power input into light emission (i.e., with minimal losses due to conversion into other forms of energy such as heat). Previous studies on LEDs based on 2D semiconductors reported that a large amount of electrical current is needed to trigger light emission. This means that a substantial fraction of the input electrical power is dissipated as heat instead of generating light.
By: Clifford Johnson, University of Southern California – Dornsife College of Letters, Arts and Sciences
Science is one thread of culture – and entertainment, including graphic books, can reflect that. ‘The Dialogues,’ by Clifford V. Johnson (MIT Press 2017), CC BY-ND
How often do you, outside the requirements of an assignment, ponder things like the workings of a distant star, the innards of your phone camera, or the number and layout of petals on a flower? Maybe a little bit, maybe never. Too often, people regard science as sitting outside the general culture: A specialized, difficult topic carried out by somewhat strange people with arcane talents. It’s somehow not for them.
But really science is part of the wonderful tapestry of human culture, intertwined with things like art, music, theater, film and even religion. These elements of our culture help us understand and celebrate our place in the universe, navigate it and be in dialogue with it and each other. Everyone should be able to engage freely in whichever parts of the general culture they choose, from going to a show or humming a tune to talking about a new movie over dinner.
Science, though, gets portrayed as opposite to art, intuition and mystery, as though knowing in detail how that flower works somehow undermines its beauty. As a practicing physicist, I disagree. Science can enhance our appreciation of the world around us. It should be part of our general culture, accessible to all. Those “special talents” required in order to engage with and even contribute to science are present in all of us.
So how do we bring about a change? I think using the tools of the general culture to integrate science with everything else in our lives can be a big part of the solution.
A new water-based air-conditioning system cools air to as low as 18 degrees Celsius (about 64 degrees Fahrenheit) without using energy-intensive compressors and environmentally harmful chemical refrigerants.
This technology could potentially replace the century-old air-cooling principle that is still used in modern-day air-conditioners. Suitable for both indoor and outdoor use, the new system is portable and can be customized for all types of weather conditions.
The team’s novel air-conditioning system is cost-effective to produce, and it is also more eco-friendly and sustainable.
Incorporating organic electronic materials in the field of bioelectronics has indicated promising potential in interfacing with biological systems, including neuroscience applications. Researchers from Linköping University are taking a major step forward in that work with their development of the world’s first complementary electrochemical logic circuits that can function for long periods of time in water.
While the first printable organic electrochemical sensors appeared as early as 2002, significant advancements have developed in a few years. Organic components such as light-emitting diodes and electrochemical displays are already commercially available.
This from Linköping University:
The dominating material used until now has been PEDOT:PSS, which is a p-type material, in which the charge carriers are holes. In order to construct effective electron components, a complementary material, n-type, is required, in which the charge carriers are electrons.
A team of researchers from the University of Toronto is looking to give wasted materials new value by developing a new catalyst that could help recycle carbon dioxide into plastic.
According to a new study, the researchers have successfully used a new technique to efficiently convert carbon dioxide to ethylene, which can then be processed to make polyethylene, the most common plastic used in making packaging, bottles, and toys.
By using a copper catalyst, the team was able to achieve the desired result of ethylene production. However, controlling the catalyst was one of the technological challenges the team had to overcome.
Superior high-voltage performance of Li-ion full cell with Li-rich layered oxide cathode prepared with fluorinated polyimide (FPI) binder, compared to the cell with conventional binder PVdF. (Click to enlarge.)
Image: Seung Wan Song
In order to increase the driving range of electric vehicles, researchers across the globe are working to develop lithium-ion batteries with higher energy storage. Now, scientists at Chungnam National University and Kumoh National Institute of Technology in Korea are taking a step toward that goal with their development of the first high-voltage cathode binder for higher energy Li-ion batteries.
Today’s Li-ion batteries are limited to charge to 4.2V due to the electrochemical instability of the liquid electrolyte and cathode-electrolyte interface, and loosening of conventional binder, polyvinylidenefluoride (PVdF), particularly at elevated temperatures. The fabrication of Li-rich layered oxide cathode with a novel high-voltage binder, as the research team demonstrated, can overcome these limitations.
Charging the batteries with Li-rich layered oxide cathode (xLi2MnO3∙(1−x)LiMO2, M = Mn, Ni, Co) to higher than 4.5V produces approximately doubled capacity than those with LiCoO2 cathode, so that doubled energy density batteries can be achieved.
A new method to quickly produce fibers from carbon nanotubes is both handmade and high tech.
The method allows researchers to make short lengths of strong, conductive fibers from small samples of bulk nanotubes in about an hour.
In 2013, Rice University chemist Matteo Pasquali found a way to spin full spools of thread-like nanotube fibers for aerospace, automotive, medical, and smart-clothing applications. The fibers look like cotton thread but perform like metal wires and carbon fibers.
