TU-TESL

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According to foreign media reports, catalysts can accelerate chemical reactions, but the metal platinum widely used in catalysts is not only very rare, but also very expensive. As a result, researchers from Eindhoven University of Technology (TU / E) in the Netherlands, in collaboration with researchers from China, Singapore and Japan, have developed a 20 fold higher activity alternative: a hollow nano catalyst made of nickel and platinum alloys. Emiel Hensen, a researcher at Eindhoven University of technology, hopes to use the new catalyst to develop an electrolytic cell about 10 megawatts, the size of a refrigerator, in the future. By 2050, the Dutch government hopes to use sustainable energy such as solar energy or wind energy to meet the energy demand of the whole country. Because such energy is not available at all times, it is important to be able to store such renewable energy. Due to the low energy density of the battery, it is not suitable for storing a large amount of energy. A better solution is to use chemical bonds. Hydrogen is the best gas chemical bond. Using water, the cell converts (excess) electrical energy into storable hydrogen. Instead, stored hydrogen is converted to electricity, but both technologies need catalysts to power them. Due to its high activity, the catalyst can help with conversion, and is mostly composed of platinum. However, platinum metals are very expensive and relatively scarce, which can be an obstacle if large-scale use of electrolyzers and fuel cells is desired. "As a result, Chinese researchers have developed a platinum nickel alloy that reduces the cost of the catalyst and increases its activity," said emiel Hensen, a professor of catalytic chemistry at TU / E With high activity of effective catalyst, more water molecules can be converted into hydrogen per second. In addition to selecting other metals, the researchers were able to make significant changes in the shape of the fuel cell. The atoms in the catalyst must bond with water and / or oxygen molecules to be able to convert them. Therefore, the more the bonding sites, the higher the activity. "It is necessary to create as large a metal surface as possible for the hollow nanomaterials developed to be able to enter both internally and externally, creating the largest surface area so that more materials can react at the same time," Hensen said In addition, Hensen also proved that the specific surface structure of nano materials further increased the activity of the catalyst by using quantum chemistry technology. After calculation in Hensen's model, it is found that the activity of platinum nickel alloy supported catalyst is 20 times higher than that of current platinum catalyst. The researchers also found the same result in fuel cell experiments. "Many critics of basic research say that this kind of research is completed in the laboratory, and it is often ineffective when applied to real equipment. However, we have proved that this new catalyst has practical application value. " The catalyst must be stable enough to work in a hydrogen powered vehicle or house for several years. Therefore, researchers have tested the catalyst in a fuel cell for 50000 cycles, and found that its activity has hardly declined. The new catalyst has a wide range of applications, which can be used not only for fuel, but also for the reverse reaction in the electrolytic cell. For example, fuel cells can be used in hydrogen powered vehicles, and some hospitals have used batteries to power emergency generators. The electrolyzer can be used in offshore wind farms and even wind turbines. Transporting hydrogen is much cheaper than transporting electricity. Hensen's dream is bigger, he said: "I hope we can install the electrolyzer in every block. The refrigerator sized device can store all the energy in the form of hydrogen in the daytime from the solar panel on the nearby roof. In the future, the underground natural gas pipeline can deliver hydrogen, and the domestic central heating boiler will be replaced by fuel cell, which can convert the stored hydrogen into electric energy, so that solar energy can be fully utilized. " However, in order to achieve this, we need to develop electrolyzers. Together with other Tu / E researchers and industrial partners in the Brabant region, Hensen participated in the work of the Institute of energy research, Eindhoven University of technology, aiming to transform the existing commercial cell into a refrigerator sized cell with a capacity of 10 megawatts. (all pictures in the article are from Eindhoven University of Technology)