U.S. Develops Nanocomposites with High Efficiency for Hydrogen Storage

Highly efficient storage of hydrogen in nanocomposites consists of metallic magnesium and polymers, which can rapidly absorb and release hydrogen at room temperature. According to a report recently organized by the American Physicists Network, American scientists have designed a new hydrogen storage nanocomposite material. The composition of metal magnesium and polymer can quickly absorb and release hydrogen at room temperature, which is another major breakthrough in the fields of hydrogen storage and hydrogen fuel cells.

In the 1970s, people began to view hydrogen as a substitute for fossil fuels and placed great hopes on it because the by-product of hydrogen combustion is only water, and other hydrocarbon fuels emit greenhouse gases and harmful pollutants. In addition, compared to gasoline, hydrogen is lighter in weight, more energy-dense, and more abundant in source.

But if hydrogen wants to replace gasoline as fuel, it must solve two major problems: how to store safely and densely, and how to obtain it more easily. In recent years, scientists have been trying to solve these two problems. They try to "lock in" the hydrogen in the solid; try to store more hydrogen in a smaller space, and let the hydrogen reactivity is very low - to make hydrogen, a volatile substance, to remain stable and low reactivity Very important. However, most solids can only absorb a small amount of hydrogen. At the same time, the entire system needs to be heated or cooled to increase its energy efficiency.

Now, scientists at the U.S. Department of Energy's Lawrence Berkeley National Laboratory have designed a new nano-hydrogen storage composite that is made of metal magnesium nanoparticles scattered in a polymethyl methacrylate (polymer resin-related polymer) matrix. composition. The new material can quickly absorb and release hydrogen at normal temperature, and magnesium metal will not oxidize in the cycle of absorbing and releasing hydrogen.

Researcher Jeffer Ebern said that this study shows that in the design of nanocomposites, they can break through the basic thermodynamic and dynamic barriers to allow substances to be well-integrated; and they can also effectively balance new composite materials. In the polymer and nano-metal particles, so as to provide reference for other energy research areas to solve related problems.

Erben and co-worker Kristian Keithowski used a TEAM 0.5 microscope from the National Electron Microscopy Center under the U.S. Department of Energy to observe individual magnesium nanocrystals scattered within the polymer. The TEAM 0.5 microscope is the most powerful electron microscope in the world and can directly observe and analyze nanostructures at a resolution of 0.5 Angstroms (approximately one third of the size of a carbon atom and a critical dimension for atomic-scale studies). Using the microscope, researchers can also trace the "snaps" - irregular ordering and atomic vacancies within the crystal. With this, scientists can understand the behavior of hydrogen atoms in new storage materials with unprecedented precision and accuracy.

Keith Lozki said: "Using the TEAM 0.5 microscope, we can confirm that hydrogen is present in this material and can directly photograph the hydrogen atoms in the new material, allowing us to better observe the behavior of hydrogen atoms."