In situ exsolution nanophase decorated perovskite cathode for solid oxide electrolysis cells with efficient CO2 electrolysis performance

CO2 electrolysis using solid oxide electrolysis cells is a promising technology for CO2 utilization and conversion, which has attracted more and more attention in recent years because of its extremely high efficiency. However, traditional Ni-yttria-stabilized zirconia (Ni-YSZ) or Ni–Gd0.1Ce0.9O2−δ (Ni-GDC) metal-ceramic cathode faces many problems such as Ni agglomeration and carbon deposition during long-time operation. Herein, a perovskite oxide La0.43−xCa0.37Ti0.9Ni0.1O3−δ (LCTN, x = 0, 0.05, 0.1) with nanophase-LaVO4 exsolution was investigated as the novel cathode of solid oxide electrolysis cell (SOEC) for efficient CO2 electrolysis. The results confirm that the exsolution nanophase on LCTN surface can significantly improve the CO2 adsorption and conversion performance. For CO2 electrolysis at 1.8 V, an electrolysis current density of 1.24 A/cm2 at 800 °C can be obtained on SOEC with La0.43−xCa0.37Ti0.9Ni0.1O3−δ decorated with LaVO4 (LCTN-V0.05) cathode. Furthermore, the corresponding cell can maintain stable operation up to 100 h without apparent performance degradation. These results demonstrate that doping-induced second nanophase exsolution is a promising way to design high-performance SOEC cathodes for CO2 electrolysis.