NEWS RELEASE 10-DEC-2024
New concept for sustainable fuel cell polymer electrolytes overcomes barriers in high-temperature, low-humidity use, advancing net-zero carbon goals
Peer-Reviewed Publication
NAGOYA UNIVERSITY

A research group led by Atsushi Noro at Nagoya University in Japan has announced a novel design concept for fuel cell electrolytes, utilizing a phosphonic acid polymer with hydrocarbon spacers. This innovative concept allows fuel cells to operate effectively under high-temperature (above 100°C) and low-humidity conditions, addressing crucial barriers to their broader use. The research has been published in ACS Applied Polymer Materials.

By electrochemically reacting hydrogen and oxygen, fuel cells produce electricity while emitting only water, highlighting their clean energy capabilities. However, perfluorosulfonic acid polymers, a type of per- and polyfluoroalkyl substance (PFAS) commonly used in fuel cells is causing a backlash. The presence of PFAS in the environment and their accumulation within living organisms has prompted regulatory measures in many nations.

Unlike PFAS, phosphonic acid hydrocarbon polymers do not contain fluorine, making them less likely to persist in the environment. These polymers also exhibit moderate chemical stability under high-temperature and low-humidity conditions. Despite these advantages, poor conductivity and the hydrophilic nature of phosphonic acid groups, which attract water, limit their use, potentially leading to dissolution in humid environments.

To overcome these challenges, Noro introduced a hydrophobic spacer between the polymer backbone and the phosphonic acid groups of a phosphonic acid hydrocarbon polymer. This enabled water insolubility, chemical stability, and moderate conductivity, even at high temperatures and low humidities. Additionally, the hydrophobic spacer effectively repelled water, ensuring that the material’s stability was maintained.

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