iMatSci at the 2022 MRS Fall Meeting & Exhibit

Congratulations to our 2022 Winners!

First Place  Aaron Baskerville-Bridges, AeroShield Materials, Inc. Transparent, Super-Insulating Silica Aerogels	Second Place George Boyajain, Mussel Polymers, Inc. Catechol Coatings for Wet Adhesions, Carbon Fiber, Dental and Biomed Applications	Third Place Dan Esposito, Guardion, Inc. Advancing Trace Detection of Matter with 2D Materials
Chemical Angel Network - $10,000 Investment Prize Patrick Rivelli, Hyunwoo Yuk  SanaHeal, Inc. Barnacle Glue-Inspired Hemostasis in Seconds

2022 MRS Fall Meeting & Exhibit: Science as Art Competition

Congratulations to our winners! 

Nanostructured Carbon Leviathan

Gerardo Pagano, Politecnico di Milano/Istituto Italiano di Tecnologiaes

The image was taken during an SEM analysis of a nanostructured carbon thin film. During the annealing the film peeled away taking with it some pieces of the silicon substrate.

 

Walking in a Wolfram Wonderland

Alexander Sredenschek, The Pennsylvania State University

This scanning electron microscope (SEM) image was taken with the electron beam tilted at an angle of 45° with respect to the sample stage normal. The image shows a perspective view of the step edges and dendritic growth in the tungsten carbide crystals, transferred onto SiO2/Si, that resemble snowflakes with fractal-like patterns and quasi six-fold symmetry.

 

O Christmas Ti, O Christmas Ti, How Lovely Are Thy Defects

Kate Reidy, Massachusetts Institute of Technology

This tree-mendous TEM image shows titanium (Ti) dislocation networks on graphene. Imaged by Themis Z microscope at MIT.nano in high angle annular dark field (HAADF) mode. Scale bar 100 nm. Image credits: Kate Reidy, George Varnavides, and Aubrey Penn. 

 

MXene Dragon

Anupma Thakur, Indiana University-Purdue University Indianapolis

MXene dragon is born from the MAX dragon, and is watching from its realm! This image shows a multi-layered titanium carbide MXene flake visualized as a dragon. If you want to conquer the MXene world, you best have dragons! The imaging technique is field emission scanning electron microscopy, and the image width is about 10 micrometers.

 

Tiny GaN Village with Graphene River Passing Through

Hyunseok Kim, Massachusetts Institute of Technology

The gallium nitride (GaN) buildings, or nano-rods, are grown on top of wet-transferred graphene on GaN by remote epitaxy. The river corresponds to folded graphene, a common defect created during wet transfer. Image was taken by scanning electron microscopy (SEM).

 

On the Beach of the Lithium Sea

Yue Deng, Cornell University (not pictured)

A scanning electron microscopy image showing the edge of a lithium deposit. The tides and sea as seen in this image are electrochemically deposited lithium, and the beach is a polished copper current collector. This image reveals the low-density structure at the edge of an electrochemically deposited lithium. Scale bar is 100 um. 

 

 

 

2022 MRS Fall Meeting & Exhibit - Best Poster Awards

Monday, November 28

Daria Bukharina, Georgia Institute of Technology

Joo Sung Kim, Seoul National University

Seongjae Kim, Gachon University

Hyeseon Lee, Pusan National University

Simo Pajovic, Massachusetts Institute of Technology

 

Tuesday, November 29

Sydney Morris, Brown University

Hyungcheoul Shim, Korea Institute of Machinery and Materials (KIMM), Korea University of Science and Technology (UST)

Jun Meng, University of Wisconsin-Madison

Watcharaphol Paritmongkol, Massachusetts Institute of Technology

Youngji Kim, Ewha Womans University

Yuxin Song, Tohoku University

 

Wednesday, November 30

Jessica Andrews, University of Southern California

Tonghui Wang, North Carolina State University

Young Moon Choi, Yonsei University

Somi Kim, Gachon University

Eliza Price, Massachusetts Institute of Technology

Qiyi Fang, Rice University

 

Virtual Poster

Shigeyuki Imura, NHK Science & Technology Research Laboratories

David Turnbull Lectureship

Chang-Beom Eom, University of Wisconsin-Madison

Complex Oxide Heterostructures: How did we get here and where are we going?

Written by Rahul Rao

In his David Turnbull Lecture, Chang-Beom Eom of the University of Wisconsin–Madison spoke not only about his own group’s work with thin-film epitaxy of oxide materials, but about the field at large. He discussed several recent breakthroughs in complex oxide thin films, how the field had progressed in the past decades. Eom concluded by listing a pair of the latest obstacles facing better thin films and how his group had begun surmounting them.

Engineers and materials scientists have taken an interest in complex oxides due to their wide range of properties, everything from piezoelectricity to ferromagnetism to superconductivity, that are particularly useful for applications in electronics. Complex oxides come in varying forms, including ceramics and single crystals, and there are multiple ways to prepare them.

But Eom’s talk and work both focused on thin films grown through epitaxy, which have a few lustrous qualities for researchers. Epitaxial thin films lack the grain boundaries often found in ceramics, making thin films’ properties easier to study. Researchers can also control epitaxial thin films’ orientation, and thin films are riper for strain engineering.

But it wasn’t until very recently that researchers knew how to grow complex oxides in thin-film form. Eom first encountered the idea as a graduate student working on high-temperature superconductors in the late 1980s, when a colleague hacked together a method of growing a superconductor on a substrate of strontium-based artificial gemstone. This relatively primitive ex situ method, Eom said, had a number of severe limitations. It produced roughly textured layers that smeared into each other, which made crafting multilayer structures prohibitively difficult.

To get around this, Eom and other researchers in the 1990s developed a new in situ method. That came with its own challenges; the layers were challenging to control, and they required high oxygen pressure for stability—something incompatible with traditional vacuum systems. To overcome these challenges, researchers developed a new pumping system with multiple pressure levels.

Epitaxial complex oxide films have advanced in leaps and bounds since the 1990s, but researchers working with them still face formidable challenges. One how to find, control, and zap out defects, a goal that’s especially pressing to anybody working with semiconductors or electronics. The key, Eom said, is to achieve greater control over the thin films. To that end, Eom’s group has tinkered with a new chemical pulsed laser deposition approach.

Another challenge is that, while epitaxy is good at making multiple layers with similar layers, it struggles to deposit multiple, starkly distinct properties. Doing this could create better and more optimal methods, but it will require currently experimental methods. Eom discussed several methods his group was trying out, including growing films on graphene or growing them on a “sacrificial layer” that could be peeled away.

Such methods can create a previously unexplored type of thin film: a bilayer heterostructure whose layers are slightly twisted with respect to each other.

Chang-Beom Eom received the David Turnbull Lectureship for his “pioneering research and insightful lectures on epitaxy of oxide materials and its impact on applications in electronics.”

The David Turnbull Lectureship recognizes the career contribution of a scientist to fundamental understanding of the science of materials through experimental and/or theoretical research. In the spirit of the life work of David Turnbull, writing and lecturing also can be factors in the selection process.

Von Hippel Award

Samuel I. Stupp, Northwestern University
New Frontiers in Supramolecular Design of Materials
Written by Sophia Chen

In honor of receiving the Von Hippel Award, Samuel Stupp of Northwestern University delivered a talk on Wednesday titled “New Frontiers in Supramolecular Design of Materials.”

Stupp is a pioneer in the field of self-assembling, or supramolecular, materials. Researchers create these materials by exploiting noncovalent bonds, such as hydrogen bonds or electrostatic bonds, between molecules to form predesigned structures. Over several decades, Stupp’s exploration of the fundamental science of these materials has now led to budding applications in renewable energy, robotics, and medicine.

Stupp recounted some of the early days in his lecture. In one early experiment, published in 1997, his team showed that they could build a single molecule which then self-assembled into a mushroom-shaped nanostructure. “This was really an important breakthrough for our lab because we showed how you could program a material using a single molecule and let everything else across the scales happen spontaneously,” he said.

As they have learned to test and design these materials, Stupp’s group has also demonstrated promising applications of self-assembling materials. He highlighted a light-harvesting system inspired by chloroplasts, found in the leaves of plants, which absorbs sunlight to produce energy for the plant. Their created material is a hydrogel that self-assembles into a ribbon-like structure. They have demonstrated that these materials can harvest sunlight to produce hydrogen fuel. “Making solar fuels doesn’t have to be always about a large chemical plant,” Stupp said.  

The vision is to create an object as versatile as a tree that can convert sunlight and molecules into fuel or some other desired product. “A tree can be anywhere,” Stupp said. “[…] We could coat its surfaces, and we could shape them in any way we want.”

He also presented research on supramolecular materials in soft matter experiments. This work centered on developing materials that can swim, bend, and crawl in response to low-energy stimuli, such as light or magnetic fields. In one early case, his group developed a polymer that becomes hydrophobic in response to light. Then, the material shrinks by expelling water, which the researchers can design into a structure that moves. This prototype material could bend on the order of minutes and crawl over hours.

Building on that work, the research team also made a faster system that responds to magnetic fields. The material is made of ferromagnetic nanowires. It walks in water at about 1 step per second. The researchers created a system that responds to light to pick up cargo, rolls in response to a magnetic field, and then releases the cargo in response to another light signal. The researchers are able to make it bend in seconds rather than minutes

In 2021, Stupp’s group injected paralyzed mice with a supramolecular material and showed that they recovered the ability to walk in four weeks. The research team designed the materials to trigger activity in cells in injured spinal cords. The materials biodegrade within 12 weeks of injection.

The research group could control the speed of the motion of the injected molecules and found that faster moving molecules resulted in more significant recovery.  “It’s fascinating to think about what we could do with materials with such subtle changes, dictated by the chemical structure,” Stupp said.

Stupp ended the lecture with his thoughts on the future of the field. Machine learning and atomistic simulations will help accelerate the discovery of new self-assembling materials, he said. Another future direction is to combine different types of supramolecular materials. He described these molecule combinations in analogy with alloys in metallurgy. The field will also continue to draw on biology-inspired structures and should explore combinations of synthetic and natural molecules.

Stupp received the award “for pioneering contributions to the development and understanding of a broad range of molecularly designed supramolecular soft materials that function as bioactive scaffolds in regenerative medicine, matrices for photocatalytic activity, and stimuli-responsive robotic structures.”

The Von Hippel Award, the Materials Research Society’s highest honor, recognizes those qualities most prized by materials scientists and engineers—brilliance and originality of intellect, combined with vision that transcends the boundaries of conventional scientific disciplines.

Nominate a deserving colleague for an MRS Award!

The MRS Awards Committee oversees all society awards according to policies approved by the Board of Directors, arranges for the preparation and presentation of awards, and oversees publicity for all awards.

MRS TV talks to Awards Committee chair Suveen Mathaudhu about the society’s awards program. Find a complete list of MRS awards at https://www.mrs.org/awards.

 

 

MRS Award Recipients Lightning Talks and Panel Discussion

Written by Don Monroe

Suveen Mathaudhu of the Colorado School of Mines, chair of the MRS Awards Committee, moderated the Lightning Talks session featuring award recipients. The MRS awards encompass eminent researchers with a lifetime of achievements as well as researchers just embarking on their careers. Mathaudhu encouraged listeners to consider nominating deserving colleagues, especially those from underrepresented groups.

Each of the six award recipients presented eight-minute highlights of the recognized research. These presentations were followed by a brief panel discussion.

Lightning Talks

Chad A. Mirkin of Northwestern University was awarded the MRS Medal “for the invention and implementation of nanoparticle mega-libraries for materials discovery.” He and his colleagues have developed a “new approach to materials discovery”: scanning-probe techniques to deposit huge arrays of attoliter or smaller “polymer nanoreactors,” whose composition or size systematically varies with position. Thermal treatment produces nanoparticles of metal alloys, metal oxides, sulfides, and other materials. The resulting “megalibraries” contain millions or even billions of compositions, more than have been characterized in history, Mirkin said, with “a lot of shots on goal.” Among the successes to date are the identification of new catalysts for nanotube growth and metal-alloy nanoparticles with two distinct phases. Taking full advantage of the libraries also requires corresponding automated characterization tools. The resulting high-quality “first-person” data is now being used to train machine-learning systems to help explore the “matterverse,” Mirkin said.

The Materials Theory Award was granted to George Schatz of Northwestern University “for pioneering theoretical advances in the properties of plasmonic nanostructures, self-assembly models for soft materials, and the discovery of lattice plasmon polaritons.” Plasmons, the collective oscillations of conduction electrons, give rise to dramatic absorption peaks for colloids of metal particles. The size dependence of this effect is well-predicted by Mie Theory, Schatz said. Arrays of nanoparticles also show a sharp spectral feature determined by their spacing, which can even lead to laser action. The resonant field enhancement associated with nanoparticles also leads to the well-known surface-enhanced Raman scattering, and affects absorption, fluorescence, resonant energy transfer, and nonlinear optics. For small nanoparticles, “Classical electrodynamics is sometimes not enough,” Schatz said. Quantum mechanics calculations can pick up the job for particles a few nanometers in size, however. These calculations are helping drive research in plasmon-driven chemistry, in which the optical energy is transferred to electrons to drive photochemical reactions.

Kelsey A. Stoerzinger of Oregon State University received the MRS Nelson “Buck” Robinson Science and Technology Award for Renewable Energy. Although renewable energy sources such as solar and wind are being much more affordable, getting their full benefits demands dealing with many other challenges, Stoerzinger said. One important aspect is storage of the intermittent energy, for example through liquid fuels or hydrogen generated from electrolysis. The efficiency of water splitting is limited by the oxygen evolution reaction at the anode, which currently drives the use of precious metal catalysts. Using an alkaline electrolyte “opens up a world of different transition-metal oxides that you can look at to drive this reaction instead,” Stoerzinger said, typically based on abundant metals like nickel, iron, and cobalt. She has been using surface-science tools to study highly controlled surfaces to clarify the role of crystal orientation, defects, and other details on the activity of potential catalysts.

The Kavli Foundation Early Career Lectureship in Materials Science went to Aaswath Raman, University of California, Los Angeles, who devoted his short talk to “thermal photonics.” The thermal radiation is “omnipresent,” but manipulating the spectral or direction dependence of materials’ emissivity makes new applications possible. For example, thermal emission aligned with the atmospheric transmission window, at wavelengths around 8 to 13 microns, can cool an object well below the ambient temperature. “This is not just research,” Raman said, but is being pursued for commercial use in cooling water. Such passive cooling could even be used to desalinate water through freezing, as opposed to the familiar but energy-intensive distillation. “There is actually hope for this technology to compete,” Raman said, with the familiar, energy-intensive distillation. Multiscale metamaterials can also enhance infrared emissivity of ultralight laser-propelled sails being explored for interstellar exploration. Raman also described layered structures exploiting epsilon-near-zero materials to control the direction of emissivity.

The MRS Postdoctoral Award is granted to two early-career researchers. One award went to Kenji Yasuda of the Massachusetts Institute of Technology “for the discovery of atomically-thin interfacial ferroelectricity in van der Waals heterostructures.” These structures are created from layers of two-dimensional materials, including combining different compositions. “We can stack these materials…to create artificial heterostructures that do not exist in nature,” Yasuda said. In particular, a pair of boron nitride layers, stacked in parallel, develops an out-of-plane electrical polarization whose direction depends on the alignment between the layers. Interlayer sliding switches the polarization, a mechanism he described as “quite unique.” This ferroelectricity persists up to room temperature, and nanosecond-scale switching suggests possible application as a memory. Ferroelectricity was also observed in layered dichalcogenides.

The other MRS Postdoctoral Award was given to Liang Feng of Northwestern University “for discovery of mechanisorption, a fundamentally new mode of adsorption.” Unlike physisorption and chemisorption, this new mechanism can operate far from equilibrium, Feng said. “Mechanisorption is totally different,” and can load a surface with very high, nonequilibrium concentrations of a molecule. Feng likened this nonequilibrium pumping to biological ATP-driven pumps that transport ions against concentration gradients. The work uses molecular rings that have a “mechanical bond” to a linear molecule that passes through them. Loading a ring is controlled by a chemical group on the chain whose charge state can be modified electrochemically or electrically. Feng and his colleagues have demonstrated one-way transfer process as well as the ability to transfer up to 10 rings onto a long collecting chain.

Panel Discussion

In response to an audience question in the brief panel discussion following the talks, the speakers all described failures they had experienced in their research. Such failures happen “every day,” Mirkin said.

But research surprises can also lead to serendipitous discoveries, they said in response to a query from Mathaudu. Mirkin noted that his well known dip-pen lithography technique was adapted from the frequently troublesome condensation of water in the vicinity of scanning-probe microscope tips. Schatz said that the initial study of arrays of metal particles was started to explore their interactions in close proximity. The wider spacings that led to dramatic polariton effects were investigated only for completeness. Researchers should not ignore unexpected results, Feng said, because they “might be something interesting.”

MRS acknowledges the generosity of Dr. Gwo-Ching Wang and Dr. Toh-Ming Lu  in endowing the MRS Medal and the Materials Theory Award. MRS acknowledges the generosity of Sophie Robinson for endowing this award in memory of her father, Nelson "Buck" Robinson. The Kavli Foundation is dedicated to advancing science for the benefit of humanity, promoting public understanding of scientific research and supporting scientists and their work. MRS acknowledges the Jiang Family Foundation and MTI Corporation for their generous contribution to support of the MRS Postdoctoral Award.

 

Plenary Session Featuring The Fred Kavli Distinguished Lectureship in Materials Science

Jenny Nelson, Imperial College London

Optimizing Solar Energy Conversion in Molecular Electronic Materials

Written by Rahul Rao

Today, the solar energy world is ruled by crystalline silicon. But recent advances in materials have spawned a host of alternative materials seeking to challenge silicon’s dominance. One class of challengers are molecular electronic materials: carbon-based organic semiconductors that can be excited by visible light.

At Monday’s Plenary Session, Jenny Nelson spoke about the titular materials, how they’ve rapidly developed, and how her group’s work has contributed to bring these organic materials closer to viable solar cells.

Just several decades ago, these materials barely registered on solar researchers’ radars. Most of them had been fashioned from fullerenes, limiting their variety. Additionally, such materials tend to be disordered and suffer from a poor dielectric constant, hurting their prowess as semiconductors.

But by the 1990s, researchers had learned how to circumvent those restrictions by interfacing two different disordered materials—one to donate electrons, another to accept them. Since then, the materials themselves have diversified from fullerenes into a wide range of other materials that researchers could easily process and readily customize. As a bonus, researchers have found that their coupled molecular electronic materials’ properties are easy to computationally predict.

The result: solar cells made from molecular electronic materials have blossomed in efficiency, from less than 2.5% in 2002 to 11% in 2016 to over 19% in 2022.

Still, any organic solar cells have a long way to go before they can match their crystalline silicon counterparts, many of which now clear the 30% mark. Nelson said that researchers need to quantify and understand the loss in materials.

One way of doing that is to take a solar cell and run it in reverse, like an LED—pushing electrons in and watching the light that comes out. Because a physical relationship exists between that emitted light and the light absorbed when the device is operating as designed, researchers can study how close their device’s efficiency is to its ideal limit.

Through this method, by 2015, Nelson’s group had helped demonstrate that organic solar cells shed much of their energy through non-radiative loss—something that researchers could address by improving their materials. Recent efforts to do just that have helped drive much of the rapid efficiency jumps these solar cells experienced from the late 2010s.

Their efficiency could rise even farther if researchers can understand which molecular properties lead to which changes in a solar cell’s performance. Nelson’s group probed this computationally, outfitting a model of a solar cell device with a molecular model. They found that varying just four molecular parameters controlled a device’s voltage, current density, and fill factor.

And molecular electronic materials may not need separate donor and acceptor components forever. A smattering of recent research has suggested that single-molecule materials—for instance, polymers built with donor and acceptor subunits—have already reached at least 11% efficiency. Rearranging and reshaping polymers might boost that even further.

Finally, Nelson mentioned that optimal solar cell materials already exist in nature: in the photosystems of photosynthesizing plants. If materials scientists studied them, she said, their findings could light possible paths into a bright future of bountiful organic solar cells.

The Kavli Foundation is dedicated to advancing science for the benefit of humanity, promoting public understanding of scientific research and supporting scientists and their work.

MRS Postdoctoral Award recipient Aditya Sood

MRS Postdoctoral Award winner Aditya Sood of Stanford University discusses his award talk, “Towards Ultrafast Atomistic "Movies" of Operating Nano-electronic Devices.” Sood was awarded for pioneering correlated dynamic structure and transport studies, and the discovery of a new electrically-triggered metastable phase in an operating device.

 

 

MRS Outstanding Early Career Investigator Award recipient Prineha Narang

MRS TV talks to Prineha Narang of Harvard University about her Outstanding Early Career Investigator Award and her talk presentation, “Illuminating Quantum Matter.”