Thin-Film Fuel Cells using a Sodium Silicate Binder with La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ (LSCF) and LaCePr Oxides (LCP) Membranes

Sodium silicate was used as a binder to prepare LaCePr oxides (LCP) and La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ (LSCF) thin films on a Ni_0.8Co_0.15Al_0.05Li oxide ceramic substrate for the first time. The microstructure, morphology, and electrical properties of the LSCF–LCP thin films were characterized and investigated by using XRD, SEM, energy-dispersive X-ray spectroscopy, and electrochemical impedance spectroscopy. The film sintered at 600 °C presents promising density and has been successfully applied as the electrolyte membrane for solid-oxide fuel cells (SOFCs). Such a device achieved a respectable electrochemical performance with an open-circuit voltage of 1.04 V and a maximum power output of 545 mW cm⁻² at 575 °C. These findings suggest that sodium silicate is a suitable binder for the preparation of dense thin-film membranes for SOFCs. Moreover, the preparation technology based on sodium silicate eliminated degumming and high-temperature sintering, which resulted in greatly simplifying the preparation process of the thin-film fuel cell towards potential fuel cell commercialization.