Tuning the Surface Composition of Ni/meso-CeO₂ with Iridium as an Efficient Catalyst for Hydrogen Generation from...

Selective decomposition of hydrous hydrazine (N₂ H₄ ⋅H₂ O) over metal catalysts provides a promising means for onboard or portable hydrogen source applications. Studies on N₂ H₄ ⋅H₂ O decomposition catalysts mainly focus on the effects of bulk composition and structure on their performances, instead of the surface-composition-dependent properties. Herein, the synthesis of an Ir-modified Ni/meso-CeO₂ catalyst is reported by using a combination of colloidal solution combustion synthesis and galvanic replacement methods. A combination of structural characterization, control experiments, and DFT calculations reveals that the Ni-Ir alloy resulting from calcination treatment exerts a profound effect on the catalytic properties. The resulting Ni@Ni-Ir/meso-CeO₂ catalyst shows excellent catalytic performance towards hydrogen generation from N₂ H₄ ⋅H₂ O, which compares favorably with the Ni-Ir bimetallic catalysts reported to date.