Energy

University of Missouri scientists are unlocking the secrets of halide perovskites – a material that might bring us closer to energy-efficient optoelectronics. The scientists are studying the material at the nanoscale. At this level, the material is astonishingly efficient at converting sunlight into energy. To optimize the material for electronic applications, the scientists used a method called ice lithography, known for its ability to fabricate materials at the nanometer scale.

Researchers from the University of California, Berkeley; the U.S. Department of Energy’s Lawrence Berkeley National Laboratory; and the University of Cambridge have developed a practical way to make hydrocarbons – molecules made of carbon and hydrogen – powered solely by the sun. The device combines a light absorbing “leaf” made from a high-efficiency solar cell material called perovskite, with a flower-shaped copper nanocatalyst, to convert carbon dioxide into useful molecules.

Materials that conduct electricity well, like metals, also tend to conduct heat. But researchers at Drexel University, Villanova University, Temple University, Bryn Mawr College, Rice University, and Université catholique de Louvain in Belgium have discovered that MXenes, a type of material known for its excellent electrical conductivity, actually have very low thermal conductivity. This discovery challenges the usual link between electrical and heat conduction and could lead to new developments in building materials, performance apparel, and energy storage solutions.

Proteins called photosystems are critical to photosynthesis – the process used by plants to convert light energy from the sun into chemical energy. Combining one kind of these proteins, called photosystem I, with platinum nanoparticles, creates a biohybrid catalyst. Now, researchers from the U.S. Department of Energy's Argonne National Laboratory and Yale University have determined the structure of the photosystem I biohybrid solar fuel catalyst. Building on more than 13 years of research pioneered at Argonne, the team reports the first high-resolution view of a biohybrid structure.

Researchers at Rice University have found a new way to improve a key element of thermophotovoltaic  systems, which convert heat into electricity via light. Using an unconventional approach inspired by quantum physics, the researchers designed a thermal emitter that can deliver high efficiencies within practical design parameters. The emitter is composed of a tungsten metal sheet, a thin layer of a spacer material and a network of silicon nanocylinders.

Scientists from Clark Atlanta University and the Molecular Foundry at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory have discovered a faster, more sustainable method for making metal-encapsulated covalent organic frameworks – materials that have the potential to play a crucial role in catalysis, energy storage, and chemical sensing. The new one-step, room-temperature process eliminates the need for toxic solvents and significantly reduces the production time from several days to just one hour.

Researchers from the University of Chicago; the University of California, Berkeley; Northwestern University; the University of Colorado Boulder; and  the U.S. Department of Energy’s Argonne National Laboratory have developed a new technique for growing quantum dots – nanocrystals used in lasers, quantum light-emitting diode (QLED) televisions, and solar cells. The researchers replaced organic solvents typically used to create quantum dots with molten salt – literally superheated sodium chloride of the type sprinkled on baked potatoes.

Cornell University researchers have made headway into understanding how twisted bilayer graphene becomes a superconductor. In 2023, the scientists developed a theoretical formalism to compute the highest possible superconducting transition temperature in any material obtained by stacking and twisting two-dimensional materials. For the current work, the scientists applied this theoretical formalism to twisted bilayer graphene. “One of the remarkable properties of twisted bilayer graphene is the associated tunability,” said Debanjan Chowdhury, one of the scientists involved in this study.

Researchers from New York University; the Center for Functional Nanomaterials (CFN), a U.S. Department of Energy Office of Science user facility at Brookhaven National Laboratory; and the National Institute for Materials Science in Tsukuba, Japan, have used a special robotic system to assemble very large pieces of atomically clean two-dimensional materials into stacks. These materials, called graphene heterostructures, consist of sheets just a few atoms thick, have record-setting dimensions – as large as 7.5 square millimeters, which is very large in the world of microelectronics.

Researchers from the University of Illinois at Urbana-Champaign have discovered a new type of nanoparticle, palladium hydride, which contains palladium and hydrogen. Palladium hydride nanoparticles are typically structured symmetrically, looking like a cube with palladium atoms posted at each corner and centered on all six cubic faces. In contrast, the new nanoparticle’s structure is presumably the least symmetrical of all crystal systems.