Lowering the calcination temperature and boosting the electrocatalytic activity of air electrodes for solid oxide cells by the glucose–urea method†

Abstract

Efficient, cost-effective, and environmentally sustainable synthesis processes are critical for the development of high-performance air electrodes in solid oxide cells (SOCs). Traditional synthesis routes often fail to meet the dual demands of high efficiency and environmental sustainability. In this study, an eco-friendly glucose–urea method is first proposed for synthesizing the La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ (LSCF) air electrode. Compared with the conventional sol–gel method, this method can not only significantly reduce sintering temperatures, but also minimize the environmental impact by utilizing non-toxic, affordable and readily available precursors, thereby significantly lowering the carbon footprint of material production. What's more, LSCF powders with smaller and more uniform particle sizes could be obtained by using this approach, which exhibit superior electrocatalytic activity and enhanced structural stability. At 750 °C, SOCs equipped with this LSCF air electrode show a maximum power density of 1.64 W cm⁻² in fuel cell mode and a current density of 1.16 A cm⁻² (1.3 V) in electrolysis mode. A comprehensive understanding of the underlying mechanisms also facilitated the optimization of the synthesis process. This study provides a meaningful technology toward greener energy solutions and sustainable manufacturing practices by offering a cleaner, more efficient route to synthesize critical materials.