Disordered vacancy-isolated Ce-Gd-O clusters achieve exceptional low-temperature oxygen-ion conductivity for fuel cells.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 42418578.
- Also identified by DOI 10.1126/sciadv.aec8053.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Oxygen-ion conductors are central to clean energy technologies. Conventional long-range-ordered oxide-ion conductors require high operating temperatures, which increase cost and limit durability; overcoming the low temperature conductivity gap is a long-standing challenge. We created cerium (Ce)-gadolinium (Gd)-oxygen (O) clusters by thermal-shock exfoliation of fluorite Gd<sub>0.1</sub>Ce<sub>0.9</sub>O<sub>1.95</sub> and examined their structure and ion transport. These disordered, vacancy-isolated clusters form percolative oxygen-ion pathways without long-range order, delivering exceptional conductivity of 2.14 ± 0.09 siemens per centimeter at 400°C-more than 320-fold higher than most previously reported oxide-ion conductors under comparable conditions. Used as a 0.5 weight % cathode additive in solid oxide fuel cells, they tripled the peak power density to 2.87 ± 0.04 watts per square centimeter at 750°C compared with the pristine Pr<sub>0.5</sub>Ba<sub>0.25</sub>Ca<sub>0.25</sub>CoO<sub>3-δ</sub>/Gd<sub>0.1</sub>Ce<sub>0.9</sub>O<sub>1.95</sub> cathode and reversed degradation from -13.2 to +3.4% per 100 hours. These findings overturn the paradigm that high oxygen-ion conductivity requires long-range order and highlight Ce-Gd-O clusters as enablers for advanced energy technologies.