Carbon Template-assisted Sol–gel Synthesis of LaNi0.5Co0.5O3 Cathodes with Enhanced Electrochemical Performance for IT-SOFCs

This research addresses the issue of particle agglomeration and a low catalytic activity in the traditional sol–gel preparation of LaNi 0.5 Co 0.5 O 3 (LNCO). A new synthetic strategy is proposed, leveraging the combination of polyvinylpyrrolidone (PVP) serving as a complexing agent and graphene nanosheet (GN) functioning as a template, successfully producing a high-activity LNCO cathode material (GN-LNCO) with a layered structure. Various characterizations confirmed that incorporating PVP and GN effectively suppressed particle agglomeration at high temperatures. The optimized GN-LNCO exhibited excellent physicochemical properties, including a specific surface area of 45.21 m 2 g −1 , a more regular mesoporous structure, a higher electronic conductivity, and a greater oxygen vacancy concentration. Electrochemical performance tests showed that the GN-LNCO cathode demonstrated an outstanding performance in solid oxide fuel cells at 800 °C, with a peak power density of 350.91 mW cm −2 . This represented an improvement of 28.65% over the conventional LNCO. Additionally, a 72 h long-term stability test of a GN-LNCO single cell revealed a voltage decay rate of only 1.60%, indicating its excellent stability. Overall, this study provides a novel material design strategy for developing high-performance cathodes, which has significant implications for advancing solid oxide fuel cell technologies.