Nanocomposite electrodes for high current density over 3 A cm<sup>-2</sup> in solid oxide electrolysis cells.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31780713.
- Also identified by DOI 10.1038/s41467-019-13426-5 and PMC identifier 6883038.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Solid oxide electrolysis cells can theoretically achieve high energy-conversion efficiency, but current density must be further increased to improve the hydrogen production rate, which is essential to realize widespread application. Here, we report a structure technology for solid oxide electrolysis cells to achieve a current density higher than 3 A cm<sup>-2</sup>, which exceeds that of state-of-the-art electrolyzers. Bimodal-structured nanocomposite oxygen electrodes are developed where nanometer-scale Sm<sub>0.5</sub>Sr<sub>0.5</sub>CoO<sub>3-δ</sub> and Ce<sub>0.8</sub>Sm<sub>0.2</sub>O<sub>1.9</sub> are highly dispersed and where submicrometer-scale particles form conductive networks with broad pore channels. Such structure is realized by fabricating the electrode structure from the raw powder material stage using spray pyrolysis. The solid oxide electrolysis cells with the nanocomposite electrodes exhibit high current density in steam electrolysis operation (e.g., at 1.3 V), reaching 3.13 A cm<sup>-2</sup> at 750 °C and 4.08 A cm<sup>-2</sup> at 800 °C, corresponding to a hydrogen production rate of 1.31 and 1.71 L h<sup>-1</sup> cm<sup>-2</sup> respectively.