水素燃料電池用純白金触媒の代替 - リチウムイオン電池装置
2022年10月27日
Hydrogen fuel cell is a promising technology to produce clean and renewable energy, but the cost and activity of its cathode materials are the main challenges for commercialization. Many fuel cells require expensive platinum based catalysts - substances that initiate and accelerate chemical reactions - to help convert renewable fuel into electricity. To make hydrogen fuel cells commercially viable, scientists are looking for cheaper catalysts that provide the same efficiency as pure platinum.(Lithium - Ion Battery Equipment)
"Like batteries, hydrogen fuel cells convert stored chemical energy into electrical energy. The difference is that you use a complementary fuel, so in principle, 'batteries' will always exist," said Adrian Hunt, a scientist at the National Synchronous Light Source II (NSLS-II) of the Department of Energy's (DOE's) science user facility at the Brookhaven National Laboratory. "Finding a cheap and effective hydrogen fuel cell catalyst is basically the holy grail to make this technology more feasible."
In the process of searching for fuel cell cathode materials worldwide, researchers from Akron University developed a new method to synthesize catalysts - platinum and nickel - which can form octahedral (octahedral) shaped nanoparticles. Although scientists have determined that this catalyst is one of the most effective catalysts to replace pure platinum, they have not yet fully understood why it grows in the form of octahedron. In order to better understand the growth process, Akron University researchers worked with a number of institutions, including Brookhaven and its NSLS-II.
Peng Zhenmeng, the chief researcher of the University of Akron Catalytic Laboratory, said: "Understanding how the polyhedral catalyst is formed is crucial for establishing its structure performance correlation and designing a better catalyst." "The growth process of platinum nickel system is quite complex, so we have worked with several experienced groups to meet these challenges. The cutting-edge technology of Brookhaven National Laboratory is very helpful to the research of this research topic“
Using the ultra bright X-ray of NSLS - Ⅱ and the advanced performance of NSLS - Ⅱ in-situ and manipulated soft X-ray spectroscopy (IOS) beam lines, researchers revealed the chemical characteristics of the catalyst growth path in real time. Their findings were published in the journal Nature Communications.
"We used a research technology called environmental pressure x-ray photoelectron spectroscopy (ap xps) to study the surface composition and chemical state of nanoparticles in the growth reaction process," said IradwikanariWaluyo, chief scientist of IOS and co-author of the research paper. "In this technology, we irradiate a sample with x-rays, which will lead to the release of electrons." By analyzing the energy of these electrons, we can distinguish the chemical elements in the sample and their chemical and oxidation states. “
Hunter, also one of the authors of this paper, added: "This is very similar to the way the sun interacts with our clothes. The sun is roughly yellow, but once it hits a person's shirt, you can tell whether the shirt is blue, red or green“
Instead of using color, scientists identify chemical information on the surface of the catalyst and compare it with its interior. They found that in the growth reaction, platinum first formed and became the core of nanoparticles. Then, when the reaction temperature is slightly higher, platinum helps to form metal nickel, which is then separated to the surface of the nanoparticles. In the final stage of growth, the surface becomes a roughly identical mixture of two metals. This interesting synergistic effect between platinum and nickel plays an important role in the development of octahedral shape and reactivity of nanoparticles.
"The advantage of these findings is that nickel is a cheap material, while platinum is expensive," Hunt said. "Therefore, if nickel on the surface of nanoparticles catalyzes the reaction, and these nanoparticles themselves are still more active than platinum itself, it is hoped that through more research, we can find the minimum amount of platinum added and obtain high activity, thus creating a more cost-effective catalyst."
These findings depend on the advanced capabilities of iOS, where researchers can conduct experiments at higher atmospheric pressure than is usually possible with conventional XPS experiments.
"In the iOS system, we can track the composition and chemical state of nanoparticles in real time under the actual growth conditions," Varuyo said
"Like batteries, hydrogen fuel cells convert stored chemical energy into electrical energy. The difference is that you use a complementary fuel, so in principle, 'batteries' will always exist," said Adrian Hunt, a scientist at the National Synchronous Light Source II (NSLS-II) of the Department of Energy's (DOE's) science user facility at the Brookhaven National Laboratory. "Finding a cheap and effective hydrogen fuel cell catalyst is basically the holy grail to make this technology more feasible."
In the process of searching for fuel cell cathode materials worldwide, researchers from Akron University developed a new method to synthesize catalysts - platinum and nickel - which can form octahedral (octahedral) shaped nanoparticles. Although scientists have determined that this catalyst is one of the most effective catalysts to replace pure platinum, they have not yet fully understood why it grows in the form of octahedron. In order to better understand the growth process, Akron University researchers worked with a number of institutions, including Brookhaven and its NSLS-II.
Peng Zhenmeng, the chief researcher of the University of Akron Catalytic Laboratory, said: "Understanding how the polyhedral catalyst is formed is crucial for establishing its structure performance correlation and designing a better catalyst." "The growth process of platinum nickel system is quite complex, so we have worked with several experienced groups to meet these challenges. The cutting-edge technology of Brookhaven National Laboratory is very helpful to the research of this research topic“
Using the ultra bright X-ray of NSLS - Ⅱ and the advanced performance of NSLS - Ⅱ in-situ and manipulated soft X-ray spectroscopy (IOS) beam lines, researchers revealed the chemical characteristics of the catalyst growth path in real time. Their findings were published in the journal Nature Communications.
"We used a research technology called environmental pressure x-ray photoelectron spectroscopy (ap xps) to study the surface composition and chemical state of nanoparticles in the growth reaction process," said IradwikanariWaluyo, chief scientist of IOS and co-author of the research paper. "In this technology, we irradiate a sample with x-rays, which will lead to the release of electrons." By analyzing the energy of these electrons, we can distinguish the chemical elements in the sample and their chemical and oxidation states. “
Hunter, also one of the authors of this paper, added: "This is very similar to the way the sun interacts with our clothes. The sun is roughly yellow, but once it hits a person's shirt, you can tell whether the shirt is blue, red or green“
Instead of using color, scientists identify chemical information on the surface of the catalyst and compare it with its interior. They found that in the growth reaction, platinum first formed and became the core of nanoparticles. Then, when the reaction temperature is slightly higher, platinum helps to form metal nickel, which is then separated to the surface of the nanoparticles. In the final stage of growth, the surface becomes a roughly identical mixture of two metals. This interesting synergistic effect between platinum and nickel plays an important role in the development of octahedral shape and reactivity of nanoparticles.
"The advantage of these findings is that nickel is a cheap material, while platinum is expensive," Hunt said. "Therefore, if nickel on the surface of nanoparticles catalyzes the reaction, and these nanoparticles themselves are still more active than platinum itself, it is hoped that through more research, we can find the minimum amount of platinum added and obtain high activity, thus creating a more cost-effective catalyst."
These findings depend on the advanced capabilities of iOS, where researchers can conduct experiments at higher atmospheric pressure than is usually possible with conventional XPS experiments.
"In the iOS system, we can track the composition and chemical state of nanoparticles in real time under the actual growth conditions," Varuyo said