(Funded by the U.S. Department of Energy)
Researchers from the U.S. Department of Energy’s Lawrence Livermore National Laboratory, Columbia University, and the University of California, Irvine, have discovered a new mechanism that could boost the efficiency of hydrogen production through water splitting. This process relies on hydrated ion-permeable ultrathin coatings (such as porous oxide materials), which are used to select chemical species. Using advanced simulations, the scientists revealed that water confined within nanopores smaller than 0.5 nanometers shows significantly altered reactivity and proton transfer mechanisms. “This insight could pave the way for optimizing porous oxides to improve the efficiency of hydrogen production systems by tuning the porosity and surface chemistry of the oxides,” said Hyuna Kwon, one of the scientists involved in this study.

(Funded by the U.S. Department of Defense and the U.S. Department of Energy)
To function, quantum computers need to be kept very cold – just a few degrees above absolute zero. Now, researchers at Northeastern University, the University of California, Berkeley, the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, and the National Institute for Materials Science in Tsukuba, Japan, have shown that one day, it might be possible to run quantum computers at room temperature. The researchers identified novel van der Waals heterostructures (created by combining layers of atomically thin materials, including graphene) that allow control of the coherent movements of atoms out of their equilibrium positions – also called acoustic phonons – at terahertz frequencies. With current quantum computer transistors, the control of acoustic phonons is limited to the gigahertz range. So, increasing the range of these transistors into terahertz frequencies – an increase by a factor of a thousand – opens the possibility of running quantum computers at room temperature.

(Funded by the U.S. Department of Energy, U.S. Department of Defense, and the National Science Foundation)
Researchers from the U.S. Department of Energy’s SLAC National Accelerator Laboratory and Argonne National Laboratory; Stanford University; Harvard University; Columbia University; Florida State University; and the University of California, Los Angeles, have discovered new behavior in an 50-nanometer-thick two-dimensional material, which offers a promising approach to manipulating light that will be useful for devices that detect, control or emit light, collectively known as optoelectronic devices. Optoelectronic devices are used in light-emitting diodes (LEDs), optical fibers, and medical imaging. The researchers found that when oriented in a specific direction and subjected to linearly polarized terahertz radiation, an ultrathin film of tungsten ditelluride circularly polarizes the incoming light.

(Funded by the National Science Foundation and the U.S. Department of Energy)
Researchers from the U.S. Department of Energy’s Princeton Plasma Physics Laboratory and the University of Delaware have provided new insights into the variations that can occur in the atomic structure of two-dimensional materials called transition metal dichalcogenides (TMDs). The researchers found that one of the defects, which involves hydrogen, provides excess electrons. The other type of defect, called a chalcogen vacancy, is a missing atom of oxygen, sulfur, selenium, or tellurium. By shining light on the TMD, the researchers showed unexpected frequencies of light coming from the TMD, which could be explained by the movement of electrons related to the chalcogen vacancy.

(Funded by the U.S. Department of Energy)
Researchers from Drexel University, California State University Northridge, and the U.S. Department of Energy’s Lawrence Berkeley National Laboratory have provided the first clear look at the chemical structure of the surface of a two-dimensional (2D) material called titanium carbide MXene. MXenes form a family of 2D materials that have shown promise for water desalination, energy storage, and electromagnetic shielding. “Getting the first atomic-scale look at their surface, using scanning tunneling microscopy, is an exciting development that will open new possibilities for controlling the material surface and enabling applications of MXenes in advanced technologies,” said Yury Gogotsi, the researcher who led this study.