In situ exsolved Fe nanoparticles enhance the catalytic performance of perovskite cathode materials in solid oxide electrolytic cells

Abstract

Global CO₂ concentrations were reported to exceed 419.3 ppm in 2023, a 51% increase from pre-industrial levels, and emissions will reach 37.4 billion tons. The concomitant rise in global temperature resulting from the increase in atmospheric CO₂ concentration is precipitating a series of unprecedented challenges to global ecosystems. The development of innovative technologies mitigating the effects of climate change is of paramount importance. The solid oxide electrolytic cell (SOEC) represents a promising avenue for future CO₂ resource utilization within the context of electrocatalytic conversion technology. We have employed the exceptional electronic conductivity and redox stability of the La_0.7Sr_0.3CrO_3−δ substrate to enhance the efficacy of the electrolysis process. A series of La_0.7Sr_0.3CrFe_XO_3−δ (LSCF_X, X = 0, 0.025, 0.05, 0.075, 0.1) were prepared by fine-tuning the iron doping at the B-site via glycine liquid phase combustion. The LSCF_0.075 samples exhibited promising results in CO₂ electrolysis, with a CO yield of 5.25 mL min⁻¹ cm⁻² and a current efficiency of 98.12%. This represents a 4.25-fold improvement over the undoped LSC. It is noteworthy that LSCF_0.075 demonstrated exceptional catalytic stability after 50 hours of continuous operation at a high temperature. The industrialization of high-temperature CO₂ electrolysis technology hinges on the development of efficient and stable electrode materials. This study offers promising insights in this regard.