High-temperature solid-state synthesis and characterization of mixed-phase Sr₂CeO₄–SrCe_0.85Y_0.15O_3−δ ceramic: a potential proton-conducting ceramic membrane

Abstract

In a fusion reactor, tritium is produced in the blanket and recovered the tritium through extraction system. Tritium is one of the isotope of hydrogen, and strontium- and cerium-based perovskite materials are extremely useful for measuring hydrogen isotopes. Reliable and fast hydrogen isotope measurement is critical for effective tritium recovery, and Sr₂CeO₄–SrCe_0.85Y_0.15O_3−δ could be a promising candidate for hydrogen isotope sensors based on proton-conducting ceramic membranes. The mixed-phase Sr₂CeO₄–SrCe_0.85Y_0.15O_3−δ were synthesized using a solid-state reaction involving mixing–milling and high-temperature calcination. The mixture of strontium, cerium, and yttrium oxides were ground inside a high-energy ball mill and measured their particle size distribution using the dynamic light scattering method. The thermal analysis (TGA/DSC) was carried out on a mixture of SrCO₃–CeO₂–Y₂O₃ from room temperature to 1200 °C at the same time. TGA analysis revealed that the mixed materials reaction temperature ranged between 875 and 994 °C, which is supported by the endothermic peak of DSC. A proportional conversion curve is generated after estimating the temperature-dependent mass loss at 14.2% of the initial mass. TGA and DSC analysis were used to estimate the side reactions that contribute to the formation of Sr₂CeO₄. Mixed-ground raw materials were isothermally calcined for 2 h inside the muffle furnace at 800, 1000, 1100, and 1200 °C. TGA and stoichiometric estimates are used to compare the total mass loss of the reactions. The resulting products are examined using X-ray diffraction, and the lattice parameters are estimated using the cell refinement method. The materials are two-phase materials composed of Sr₂CeO₄ and SrCe_0.85Y_0.15O_3−δ. The raw and synthesized material's Raman spectra were also measured, revealing the mixed-phase material. The Raman analysis supported the diffraction data by revealing the possible modes in the compounds. This paper discusses the effect of calcination parameters on the synthesis of SrCe_0.85Y_0.15O_3−δ.