Highly active and stable Sr_0.92Y_0.08Ti_1−xRu_xO_3−d in dry reforming for hydrogen production

Biofuels such as sewage gas and landfill gas, which can be used as fuels in solid oxide fuel cells, have suitable composition of CH₄ and CO₂ for dry reforming. We developed an Sr_0.92Y_0.08Ti_1−xRu_xO_3−d material as an anode for solid oxide fuel cells that use biofuels as a direct fuel and show an excellent performance in dry reforming. The Pechini method was used to synthesize the material using ruthenium substitution in the titanium site of an Sr_0.92Y_0.08TiO_3−d (SYT) material. X-ray diffraction analysis confirmed that the perovskite phase of the synthesized catalyst was maintained. Ruthenium-loaded catalysts were prepared by coprecipitating ruthenium onto SYT to compare with the Sr_0.92Y_0.08Ti_1−xRu_xO_3−d. The differences between Sr_0.92Y_0.08Ti_1−xRu_xO_3−d and ruthenium-loaded SYT materials during methane dry reforming and the thermal stability during long-term operation were evaluated. In particular, SYTRu10 exhibited higher methane conversion and carbon dioxide conversion than Ru10-loaded SYT at the temperature range of 600–900 °C and stable performance even in long-term operation. X-ray fluorescence and Brunauer–Emmett–Teller measurements were performed to measure the composition of the catalysts and the specific surface area, pore size, and pore volume of the catalysts. X-ray photoelectron spectroscopy and temperature-programmed reduction were used to investigate the state and behavior of ruthenium. Furthermore, transmission electron microscopy was performed to analyze the shape of the catalyst before and after the reaction.