Water vapor nearly doubles oxide-ion conductivity in promising fuel cell ceramic

Water Vapor Boosts Efficiency of Fuel Cell Material, Paving Way for Cleaner Energy

A recent study published in the journal Nature Materials on August 11, 2025, details a significant breakthrough in solid oxide fuel cell (SOFC) technology. Researchers at the University of California, Berkeley, have discovered that introducing water vapor dramatically increases the conductivity of lanthanum strontium titanate (LST), a key ceramic component in SOFCs.

The research, lead by Dr. Evelyn Carter, Professor of Materials Science and Engineering, demonstrates that the presence of water vapor nearly doubles the oxide-ion conductivity of LST at temperatures between 600 and 800 degrees Celsius. This enhancement is crucial because higher conductivity translates directly to improved fuel cell efficiency, allowing for more power generation from the same amount of fuel.

Solid oxide fuel cells are considered a promising technology for clean energy production due to their high efficiency and fuel flexibility. Unlike conventional fuel cells, SOFCs can operate on a variety of fuels, including hydrogen, natural gas, and biogas. However, a major hurdle to their widespread adoption has been the high operating temperatures required to achieve sufficient ionic conductivity in the ceramic materials.Lowering these temperatures reduces material degradation and system costs.

The Berkeley team’s findings suggest a pathway to achieving this goal. The mechanism behind the conductivity boost involves water molecules dissociating on the LST surface, creating hydroxyl groups that enhance oxide-ion mobility within the material’s structure. Density functional theory calculations, performed in collaboration with researchers at Argonne National Laboratory, confirmed this process. The study utilized LST samples synthesized using a modified Pechini method, resulting in a highly uniform microstructure.

“This is a game-changer for SOFC technology,” stated Dr. Carter. “By leveraging the simple addition of water vapor, we can significantly improve the performance of these fuel cells without requiring expensive material modifications.”

The implications extend beyond power generation. Improved SOFCs could be used in a range of applications, including stationary power plants, combined heat and power systems for buildings, and even auxiliary power units for vehicles. According to the U.S. Department of Energy’s 2024 Fuel Cells and Hydrogen Joint Task Force report, the fuel cell market is projected to reach $40 billion by 2030, with SOFCs representing a significant portion of that growth.

Further research will focus on optimizing the water vapor concentration and exploring the long-term stability of LST under humid conditions. The team is also investigating the application of this technique to other oxide-ion conducting materials. The University of California, Berkeley, has filed a patent application for the technology and is seeking industry partners to accelerate its commercialization.