CGO20–CuO composites synthesized by the combustion method and characterized by H2-TPR

Abstract

CGO–CuO composites are promising anode materials for low and intermediate temperature solid oxide fuel cells (LT/IT-SOFCs). In this work, several CGO–CuO (65:35; 50:50 y 35:65mol/mol%) composites by urea combustion synthesis yielding to fine reactive powders at low temperatures were prepared. The resulting powder composites were characterized using X-ray diffraction (XRD), N2 adsorption–desorption (BET) and scanning electron microscopy-energy disperse X-ray (SEM-EDS). Additionally, hydrogen temperature programmed reduction (H2-TPR) tests were carried out, in order to elucidate reducibility of the powders. H2-TPR tests exhibited two primary reduction peaks, which correspond to the following stages: the first one (150–350°C) can be ascribed to the reduction of CuO species into metallic Cu; while the second one (750–900°C) can be ascribed to the bulk Ce4+→ Ce3+ reduction process of the support (CGO). Further, after H2-TPR reduction of the as-prepared CGO–CuO compositions, powders exhibit the presence of metallic Cu and the fluorite CGO solid solution that remains stable whereas any CuO is no longer noticed.