Scavenger nanoparticles could make fuel cell-powered vehicles a reality
New material prevents inexpensive catalysts from degrading
Date:
March 31, 2022
Source:
University of Illinois Chicago
Summary:
Engineers have developed a material that could give fuel cell
systems a competitive edge over the battery systems that currently
power most electric vehicles.
FULL STORY ========================================================================== Engineers at the University of Illinois Chicago are among a collaborative
team that has developed a material that could give fuel cell systems
a competitive edge over the battery systems that currently power most
electric vehicles.
==========================================================================
In contrast to lithium batteries, fuel cell technology relies on catalyst- driven chemical reactions to create energy. Lithium batteries can
typically achieve a range of 100-300 miles on one charge, but they also
are vulnerable to the high cost of cathode materials and manufacturing
and require several hours to charge. Alternatively, fuel cell systems
take advantage of abundant elements such as oxygen and hydrogen and can
achieve more than 400 miles on a single charge -- which can be done in
under five minutes. Unfortunately, the catalysts used to power their
reactions are made of materials that are either too expensive (i.e.,
platinum) or too quickly degraded to be practical.
Until now, that is. With the development of the new additive material, scientists can make an inexpensive iron-nitrogen-carbon fuel cell catalyst
more durable. When added to the chemical reactions, the additive material protects fuel cell systems from two of its most corrosive byproducts:
unstable particles like atoms, molecules or ions called free radicals
and hydrogen peroxide.
Findings from their experiments are reported in the science journal
Nature Energy.
Reza Shahbazian-Yassar, professor of mechanical and industrial engineering
at the UIC College of Engineering, and colleagues used advanced imaging techniques to investigate the reactions with the material, an additive comprised of tantalum-titanium oxide nanoparticles that scavenge and
deactivate the free radicals. The high-resolution imaging of the atomic structures allowed the scientists to define the structural parameters
needed for the additive to work.
"In our lab, we are able to use electron microscopy to capture
highly detailed, atomic-resolution images of the materials under a
variety of service conditions," said study co-corresponding author Shahbazian-Yassar. "Through our structural investigations, we learned
what was happening in the atomic structure of additives and were able
to identify the size and dimensions of the scavenger nanoparticles,
the ratio of tantalum and titanium oxide. This led to an understanding
of the correct state of the solid solution alloy required for the
additive to protect the fuel cell against corrosion and degradation." Experiments revealed that a solid solution of tantalum and titanium
oxide is required and that the nanoparticles should be around five
nanometers. The experiments also revealed that a 6-4 ratio of tantalum
to titanium oxide is required.
"The ratio is the key to the radical scavenging properties of the
nanoparticle material and the solid-state solution helped sustain the
structure of the environment," Shahbazian-Yassar said.
The experiments showed that when the scavenger nanoparticle material
was added to the reactions of fuel cell systems, hydrogen peroxide yield
was suppressed to less than 2% -- a 51% reduction -- and current density
decay of fuel cells was reduced from 33% to only 3%.
"Fuel cells are an attractive alternative to batteries because of their
higher driving range, fast recharging capabilities, lighter weight,
and smaller volume, provided that we can find more economical ways to
separate and store hydrogen," Shahbazian-Yassar said. "In this paper,
we report on an approach that gets us much closer to making fuel
cell-powered vehicles and other fuel cell technologies a reality."
The U.S. Department of Energy, the National Science Foundation and the
Maryland Nanocenter supported the research.
========================================================================== Story Source: Materials provided by University_of_Illinois_Chicago. Note: Content may be edited for style and length.
========================================================================== Journal Reference:
1. Hua Xie, Xiaohong Xie, Guoxiang Hu, Venkateshkumar Prabhakaran,
Sulay
Saha, Lorelis Gonzalez-Lopez, Abhijit H. Phakatkar, Min Hong,
Meiling Wu, Reza Shahbazian-Yassar, Vijay Ramani, Mohamad
I. Al-Sheikhly, De-en Jiang, Yuyan Shao, Liangbing Hu. Ta-TiOx
nanoparticles as radical scavengers to improve the durability of
Fe-N-C oxygen reduction catalysts. Nature Energy, 2022; 7 (3):
281 DOI: 10.1038/s41560-022-00988- w ==========================================================================
Link to news story:
https://www.sciencedaily.com/releases/2022/03/220331101548.htm
--- up 4 weeks, 3 days, 10 hours, 51 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)