Ten years ago, the world’s thinnest and strongest material, graphene, was isolated for the first time and hundreds of experiments were performed on it, including batteries, night-vision goggles, medical scanning equipment, light detectors, and even condoms. Until today, this material continues to surprise us. In the recently published "Nature" and "Science" magazines, British and U.S. scientists published new papers. One article pointed out that although graphene is impervious to water, it allows protons to pass through, making it possible to use ultra-thin filters in fuel cells. Membrane; Another piece of graphene is said to withstand the impact of bullets better than steel and bulletproof material.
According to Nature's website recently, Andre Gaim, a materials scientist at the University of Manchester, who invented the Nobel Prize in physics for the discovery of graphene in 2010, said that the ability of protons to pass through graphene shows that graphene can be used as a way to remove hydrogen from the air. The separate filter helps to obtain electricity from the fuel cell's hydrogen. Their paper was published in the journal Nature. Graphene can be used as a proton filter membrane.
Fuel cells can decompose hydrogen into protons and electrons, converting the chemical energy stored in hydrogen into electricity: electrons form electrical currents along external wires, and protons flow through the membrane inside the cell. Current membranes in batteries, such as commercial Nafion membranes, which are about 10 microns thick, still do not completely prevent hydrogen leakage, and protons do not flow smoothly, reducing power consumption. If there is a kind of ultra-thin ultra-thin filter, you can solve these two problems. Gaim said that this is the advantage of graphene.
However, there are fuel cell experts pointed out that this study is still in the stage of theoretical demonstration, whether it can be applied immediately and carefully. In addition, it is necessary to consider how to produce sufficiently pure, large sheets of graphene layers, factors such as cost and longevity.
The Gaim group used graphene membranes to filter pure hydrogen from water. Gail said that this technology may also separate hydrogen from the air. "This is still speculation, but before the publication of the paper, it is still in the science fiction stage." Last year, the researchers demonstrated that a stack of graphene oxide film can produce Micro channel, filter hydrogen from carbon dioxide or nitrogen.
According to a paper in the journal Science, graphene is expected to be used as a body armor material. By detecting its monolayer resistance with a diamond probe, graphene is known to be the strongest material in the world. Recently, scientists in the United States used a silica ball to shoot graphene for the first time to test its energy for impact. They found that the graphene layer quickly disperses the impact before breaking and interrupts the outward propagation of the material. The co-author of the paper, Edwin Thomas of Rice University, said that the upper limit of this effect is the speed at which sound travels through the material. In hard, light-weight graphene, the speed of sound is 22 km/s while in air. The middle is 332 meters/second. Graphene-based composites and other lightweight, high-strength materials are expected to be a "promising armor system."
James Baker, Commercial Director of the National Graphene Institute of the United Kingdom, pointed out that in all experiments, industrial partners are most concerned about manufacturing: whether the graphene layer or composites containing graphene can be manufactured on a large scale and the quality of the products is excellent. And reliable standards. (Chang Lijun)
Hem-Firm Rivet,Hem Firm Rivet,Hem Firm Rivets,Hem-Firm Rivets
KD METALS (JINGJIANG) CO.,LTD , https://www.toprivet.com