Operando measurements of processes inside PtX components​

One of the main challenges in improving fuel cells and electrolysers is that many of the most important processes take place inside the component while it is operating. Understanding these internal processes is crucial for optimising performance, reducing operating costs and material use, and improving durability and reliability. Today, much optimisation still relies on computer modelling and on measurements of external parameters such as voltage, temperature, gas production, or fuel consumption. These are important, but they do not fully reveal what is happening inside the device.

ACTNXT aims to develop advanced test benches that make it possible to study PtX components in real time, under realistic operating conditions, at neutron and synchrotron facilities. This would allow researchers and industry to observe internal phenomena such as gas bubble formation, water distribution, catalyst structure, phase changes, and ion transport while the component is running. The project’s ambition is to make such equipment compatible with a broad range of neutron and x-ray instruments at facilities such as ILL, PSI, and ESRF, enabling safe operation and wider use across the European research infrastructure landscape.

Synchrotron x-rays and neutrons offer complementary strengths in this type of research. Synchrotron x-rays are particularly valuable for very fast, high-resolution studies and for analysing the behaviour of heavier elements and fine structural changes in materials, for example in catalysts. Neutrons, by contrast, are especially powerful for analysing hydrogen-containing materials, water distribution, ion transport, and processes taking place inside metal components, because they can penetrate deeply into materials and are highly sensitive to hydrogen. Together, these methods can provide a much more complete understanding of how PtX components function under real operating conditions.

In practical terms, this can give developers a much better understanding of why a component performs well, why it degrades, and how it can be redesigned. That is important both for scientific progress and for industry, because it supports the development of more efficient, durable, and cost-effective PtX technologies.

As an example of operando study, the video shows the water distribution inside a proton exchange membrane fuel cell stack.