In this podcast episode, MRS Bulletin’s Sophia Chen interviews Lane Martin from Rice University about characterization of relaxor ferroelectrics, materials with noteworthy energy-conversion properties used in sensors and actuators. Martin’s research team investigated the material’s behavior at the nanoscale. The researchers found that the specific thin film they studied—the alloy lead magnesium niobate lead titanate—exhibited excellent properties down to 25–30 nm thick before they would start to shift. This work was published in a recent issue of Nature Nanotechnology.

In this podcast episode, MRS Bulletin’s Sophia Chen interviews Beth Dickey from Carnegie Mellon University about her new approach to inducing ferroelectricity into a material. Dickey’s research group worked with a class of materials known as wurtzites. The researchers specifically studied aluminum nitride and zinc oxide, which are not ferroelectric in their pristine form at room temperature. However, alloys of these materials are ferroelectric. When the researchers stacked the ferroelectric alloy with a non-ferroelectric wurtzite and applied electric fields to the material, they found that the crystal lattice of the ferroelectric layer began to invert, then switching propagated into the pristine wurtzite, confirming that the entire material was ferroelectric. The results of this study could lead to development of ferroelectric materials for computers where memory and computation can be brought together into a single device, saving energy. This work was published in a recent issue of Nature. 

In this podcast episode, MRS Bulletin’s Laura Leay interviews Harry Atwater from the California Institute of Technology about his study on lightsail propulsion in order to understand how the device can be developed to do fly-by space travel riding a beam of laser light. Atwater’s research group made a square prototype device where the researchers incorporated springs at each corner, etched out of a single sheet of silicon nitride, fastening it to the support frame. They tested its behavior in a two-beam interferometry experiment. Their comprehensive analysis provides a thorough understanding of key parameters that are essential for lightsail propulsion and paves the way for the next step of research: untethered flight. This work was published in a recent issue of Nature Photonics.  

In this podcast episode, MRS Bulletin’s Laura Leay interviews Ashwin Shahini and Alan Taub from the University of Michigan about their group’s simulations and experimental work detailing the formation mechanisms, morphologies, and microstructures of an in situ Al/TiC metal matrix nanocomposites processed via salt flux reaction. Using these insights, the microstructure of a material can be tuned in order to optimize the materials properties. While the three-dimensional imaging is critical to gaining insight into the structure, computational models can facilitate this optimization. This work was published in a recent issue of Acta Materialia. 

In this podcast episode, MRS Bulletin’s Sophia Chen interviews Xingchen Ye of Indiana University about his research group’s studies on the fundamental behavior of colloidal materials. Colloidal materials consist of liquids with nanoparticles suspended in them. Ye’s team is interested in how a colloidal material’s properties change as the team spatially rearranges the nanoparticles in the liquid. They looked specifically at the self-assembly of gold nanocubes into a lattice structure. Ye’s team studied how that structure gives rise to the material’s bulk properties. This work was published in a recent issue of Nature Chemical Engineering.

In this podcast episode, MRS Bulletin’s Laura Leay interviews Fabian Meder from the Italian Institute of Technology in Genova and the Sant’Anna School of Advanced Studies in Piza, Italy about his research group’s device that makes use of wind-driven plant leaf motion to generate electricity which can power a chemical delivery system. Their triboelectric nanogenerator involves an artificial leaf made of a 500 μm silicone elastomer layer and an electrode made from indium tin oxide. This is attached to the leaf of a plant. A gold-coated pin electrode inserted in the stem of the plant harvests charges from the plant tissue. This work was published in a recent issue of Bioinspiration & Biomimetic. 

In this podcast episode, MRS Bulletin’s Sophia Chen interviews Bowen Deng, a graduate student in Gerbrand Ceder’s group at the University of California, Berkeley, about their work on increasing the accuracy of artificial intelligence/machine learning materials prediction models. The use of computer simulations to predict the interaction between atoms in a given molecule is being replaced by machine learning. Researchers describe the atoms’ collective interactions as a quantity of energy, where higher energies correspond to stronger forces holding the molecule together. Now, Deng’s research group studied three machine learning models and found that they tend to predict lower energies than what is accurate by about 20 percent. The researchers have determined that these underpredictions were caused by biased training data and they found a way to remedy the situation. This work was published in a recent issue of NPJ Computational Materials.

In this podcast episode, MRS Bulletin’s Laura Leay interviews David Cahen from the Weizmann Institute of Science, Israel, about the impact surface defects have on bulk properties, specifically in the case of lead halide perovskites. In a perspective he co-authored, Cahen connected numerous experimental data from other researchers that exposed this phenomenon. By understanding how surface defects control the material’s electronic behavior, researchers can pursue new materials for the development of long-lasting devices. This work was published in a recent issue of Advanced Materials. 

In this podcast episode, MRS Bulletin’s Sophia Chen interviews Gwangmin Bae of Korea University about his work with colleagues on the design of a new smart window system that utilizes compression. Like other smart windows, this window makes use of pores within the material to adjust its transparency. However, instead of using a stretchy material that controls light scattering through the pores, Bae and colleagues used a material that compresses in thickness. That is, the window becomes more transparent when it is compressed. The researchers place this structured porous material made of the polymer polydimethylsiloxane or PDMS between two panes of glass to create the smart window. This work was published in a recent issue of Nature Communications.

In this podcast episode, MRS Bulletin’s Laura Leay interviews Leif Asp of Chalmers University of Technology about his group’s development of an all-carbon fiber-based structural battery. The negative electrode uses carbon fiber and, for the positive electrode, the carbon fiber is coated with lithium iron phosphate. In both cases the carbon fiber takes on the roles of mechanical reinforcement and current collection. This work was published in a recent issue of Advanced Materials.