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

Selective decomposition of hydrous hydrazine (N2H4 center dot H2O) over metal catalysts provides a promising means for onboard or portable hydrogen source applications. Studies on N2H4 center dot H2O 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 N2H4 center dot H2O, which compares favorably with the Ni-Ir bimetallic catalysts reported to date.