新型固体氧化物电解池阳极用于高效电催化甲烷氧化偶联OA

The work developed a La0.6Sr0.4Co0.8Fe0.2O3+δ-(Ce0.9Gd0.1)O1.95(GDC)composite anode with a novel micro-channel structure(denoted as micro-channel electrode(MCE))and fabricated a solid oxide electrolysis cell(SOEC)based on the MCE to achieve electrocatalytic oxidative coupling of CH4.The structure of MCE and the CH4 conversion performance of SOEC were characterized by using SEM,FTIR,and electrochemical measurements.The results show that when electrolyzing pure CH4 at 850℃,2.0 V,and 200 mA/cm2,the optimal SOEC achieves a high C2 product selectivity of 70.6%with no significant performance degradation over 6 000 s.In situ high-temperature infrared spectroscopy confirms that the unique micro-channel structure of MCE enhances the CH4 conversion rate,while the precisely controlled potential window suppresses the production of COx,thereby improving C2 product selectivity.DFT calculations reveal that the GDC component stabilizes active oxygen species O22-,facilitates C—H bond cleavage in CH4,concurrently inhibits oxygen evolution reaction,and stabilizes the lattice structure.The development of this composite anode provides new insights for designing high-performance SOEC anodes with novel structures and advancing the electrochemical conversion and utilization of CH4.