XAFS analysis of Ni-Zr alloys after thermal and chemical treatment

Introduction Amorphous materials have no long-range order at the atomic length scale and show different properties as compared to typical crystalline materials. Among of them, amorphous alloys are in thermodynamically nonequilibrium, crystallized by heating and used as catalysts and catalyst precursors. Investigations on the relationships between their catalytic performances and structural changes during the crystallization process of amorphous alloys are quite interesting research topics. To active catalysts, skeletal metal catalysts were also prepared by acid or base treatment of alloys. In this study, porous Ni catalysts were prepared from Ni-Zr alloys via heating at various temperatures and following HF treatment for extraction of Zr moieties. XAFS analyses were performed to clarify the effect of heating on the catalytic performances of thus obtained porous Ni catalysts.