Options
2017
Journal Article
Titel
Oxidation of La-Sr-Mn-coated interconnector alloys for steam electrolysis under pressure in pure oxygen and in pure steam
Abstract
Pressurized steam electrolysis enables an efficient conversion of electric power from renewable energy sources into hydrogen for power-to-liquids processes. The interconnector material Crofer 22 APU, uncoated and coated by La1−xSrxMnO3 (LSM), deposited by thermal spray and by roll coating was studied in pure water vapor and pure oxygen at 850 °C and 30 bar. The uncoated Crofer 22 APU forms in both atmospheres a homogeneous oxide scale from an inner Cr2O3 and an outer MnCr2O4 layer. The chromia is locally undergrown by pits of MnCr2O4. With the LSM coating, the oxide scale is notably thinner in water vapor and the formation of pits is significantly reduced. In oxygen, this effect of the LSM coating is less pronounced. Chromium from volatile species was detected in the LSM coating, more in oxygen than in water vapor. After 3000 h in pure oxygen, Crofer 22 APU with thermally sprayed LSM shows breakaway oxidation.
Author(s)