Scientists have found that the same silver nanocatalyst can carry out key oxygen reactions in different places inside a solid oxide cell, depending on whether the system is generating electricity or making hydrogen, according to ScienceDaily.
The study was led by professors WooChul Jung and Jeong Woo Han at Seoul National University, along with teams from KAIST and the Korea Basic Science Institute. Their work helps explain how silver improves solid oxide cell performance and why its behavior changes with the device’s operating mode.
To better isolate the chemistry, the researchers used a carefully designed model electrode with ordered metal nanoparticles rather than a more complex real-world electrode. They compared silver with cobalt, palladium and platinum, and found that silver gave the strongest catalytic boost.
When the cell was producing electricity, the most important reactions happened at the boundary between the silver nanoparticles and the electrode. During hydrogen production, the surface of the silver particles themselves became the main reaction site. The team says that understanding this difference could help researchers improve solid oxide cells for clean electricity and green hydrogen production.
