Sequestering nanoparticles: the hope for electric vehicle fuel cells – Technology – Hybrids and Electric

Fuel cells harness hydrogen and oxygen to create electricity, providing electric vehicles with clean energy as well as greater autonomy and very short recharging times. However, they have one of their great handicaps in the catalysts that drive the chemical reactions that take place inside them, since they are made of expensive and highly degradable materials. Engineers at the University of Illinois at Chicago have isolated what they call “sequestering particles” which has allowed them to know the exact proportion of materials of this additive for protect the fuel cell against degradation and corrosion.

Fuel cells have been the subject of multiple investigations for a long time with the aim of becoming an alternative to electrochemical batteries, especially in the transport of people and heavy goods. The technology is based on chemical reactions that create energy using elements as abundant as oxygen and hydrogen, but which require the impulse of catalysts. However, these key components are made from materials that they are too expensiveAs the platinumor what they degrade too quickly to be practical.

Therefore, it is necessary to find a suitable, practical and profitable catalyst for these devices to be technically feasible and economically profitable. According to the article published in the magazine Nature Energyengineers at the University of Illinois have developed a material that can be the solution to this problem as it is capable of producing long-lasting fuel cell systems at a competitive price compared to current lithium batteries used in electric vehicles.

The team, led by Reza Shahbazian-Yassara professor of mechanical and industrial engineering in the university’s College of Engineering, discovered a material that added to the device’s catalyst can produce a cheap and durable iron-nitrogen-carbon fuel cell.

To find it, the team turned to electron Microscopy, capable of capturing highly detailed images, at atomic resolution, of materials in a wide variety of service conditions, explains Shahbazian-Yassar. High-resolution images of the atomic structures allowed the team to define “the structural parameters necessary for the additive to work.”

While lithium batteries can reach autonomy between 150 and 500 kilometers with each charge, fuel cells can reach between 650 and 800 kilometers and recover this autonomy in just five minutes.

“Through our investigations, we learned what was happening in the atomic structure of the additives and were able to identify the size and dimensions of the sequestering nanoparticles, i.e. the ratio of specific tantalum and titanium oxide, which led to an understanding of the correct state of the solid solution alloy necessary for the additive to protect the fuel cell against corrosion and degradation.”

Ultimately, the researchers found that the best option for this protection is a solid solution of tantalum and titanium oxide, in a ratio of 6 to 4 formed by nanoparticles about five nanometers in size. “Ratio is the key to achieving the radical scavenging properties of the nanoparticles, and the solid-state solution helped maintain the structure of the environment,” Shahbazian-Yassar explains in the press release.

The material acts therefore as a “debugger” that finds and deactivates free radicals, unstable particles such as hydrogen peroxide atoms, molecules or ions, which destabilize the fuel cell. Once they solidified the parameters for the material, the researchers added it to the reactions of fuel cell systems. The result was that use of the particle suppressed the yield of hydrogen peroxide to less than 2%, over a 51% reduction caused by catalysts without the material.

Shahbazian-Yassar says this finding brings scientists closer “to making fuel cell-powered vehicles a reality.” An interesting alternative to batteries as it offers higher energy density than these and therefore greater autonomy.

The larger a vehicle is, and the longer it takes to charge the battery, the greater the disruption to its operations, and it is there where hydrogen has advantage. The technical performance of battery electric vehicles is undermined when it comes to heavy vehicles. Fuel cells offer energy storage density much greater, a greater autonomy of driving, a reduced weight and a much shorter recharging time.

While lithium batteries can achieve autonomies between 150 and 500 kilometers With each charge, the fuel cells can go up to between 650 and 800 kilometers and recover this autonomy in just five minutes since its refueling times are similar to those of a fuel tank.


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