“Water electrolysis plays a crucial role in the transition to a sustainable energy system”
Three questions to… Julius Knöppel about his research on the subject of catalyst development, recently published in Nature Communications.
Mr. Knöppel, what is the function of an electrocatalyst in a water electrolyzer?
“Electrocatalysts are a central component of the water electrolyzer electrodes, the anode, and the cathode. In these layers, the electrochemical processes of water splitting take place. A suitable electrocatalyst is a good conductor that transports charges in the electrolyzer to the reaction site and catalyzes the reaction. This means that less energy is required to drive the reaction, leading to higher hydrogen production yields with the same amount of energy.”
Your paper was recently published in the renowned journal Nature Communications. What do the results mean for the future development of water electrolyzers?
“One essential feature of an electrocatalyst in an industrial water electrolyzer is durability. To be economically promising, an electrolyzer should have a lifetime of around 10 years.
Our publication deals with the current and future testing procedures for electrocatalyst stability. Newly developed water splitting electrocatalysts are commonly tested in very simple electrochemical systems, so-called aqueous model systems. While the properties of electrocatalysts in these systems are very well studied, it has become evident that these conditions do not fully reflect on the more complex industrial water electrolyzers. Especially in terms of catalyst dissolution stability, a massive discrepancy between both systems was found. However, the complex system of an industrial water electrolyzer hampers the quantification of catalyst dissolution products in the industrial system.
Our newly developed approach tackles precisely this issue. We presented the first plausible measurement of electrocatalyst dissolution in a real electrolyzer. With our broad parameter study in the aqueous system, this is a first step towards understanding the degradation processes in a real electrolyzer. Hopefully, this knowledge will help prevent these processes in the future and, subsequently, lead to more durable electrolyzers.”
How important is research on electrocatalysts for the future utilization of renewable energies?
“Water electrolysis and other electrolysis technologies like CO2 reduction play a crucial role in the transition to a sustainable energy system. There are already operational devices on the industrial scale, but technological challenges still hamper widespread application. To overcome this issue, more research is needed. Electrocatalysts are a key component of these devices, so research on electrocatalysts is crucial for a successful transition to a new energy system.
However, the efforts will only lead to better electrolyzers, if the other components, like the membrane or bipolar plates, are enhanced accordingly.”
More information about the: New Publication in Nature Communications