Elucidating the role of interfacial charge transfer on the oxygen incorporation/evolution reactions for solid oxide cells.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41381462.
- Also identified by DOI 10.1038/s41467-025-66361-z and PMC identifier 12749743.
- Licence recorded as CC BY-NC-ND.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The oxygen incorporation and evolution reactions (OIR/OER) at air electrodes are key challenges limiting the performance of reversible solid oxide cells (SOCs). Surface modification using binary oxides has emerged as a promising strategy to enhance OIR/OER kinetics, with PrO<sub>x</sub> as a popular choice of the modification layer. However, the mechanisms behind this improvement of reaction kinetics remain unclear. In this study, we combine insights from electrochemical measurements and operando X-ray absorption spectroscopy to reveal that interfacial charge transfer plays a pivotal role in enhancing the OIR/OER activity in La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3-δ</sub> (LSCF) with PrO<sub>x</sub> surface modification. The charge transfer increases the hole concentration in LSCF, which can be quantitatively correlated with accelerated OIR/OER kinetics (up to ~70 times enhancement) over a broad range of oxygen chemical potential. We further demonstrate this mechanism in realistic SOCs devices, showing enhanced performance in both fuel cell and electrolysis modes. Our work provides critical insights into the role of interfacial charge transfer and defect chemistry in surface-modified SOCs electrodes, offering a pathway to optimize SOCs performance through surface modifications.