Pure and Ni-substituted Co3O4 spinel catalysts for direct N2O decomposition

A series of NixCo1-xCo2O4 (0 ≤ x ≤ 1) spinel catalysts were prepared by the co-precipitation method and used for direct N2O decomposition. The decomposition pathway of the parent precipitates was characterized by thermal analysis. The catalysts were calcined at 500 °C for 3 h and characterized by powder X-ray diffraction, Fourier transform infrared, and N2 adsorption-desorption. Nickel cobaltite spinel was formed in the solid state reaction between NiO and Co3O4. The N2O decomposition measurement revealed significant increase in the activity of Co3O4 spinel oxide catalyst with the partial replacement of Co2+ by Ni2+. The activity of this series of catalysts was controlled by the degree of Co2+ substitution by Ni2+, spinel crystallite size, catalyst surface area, presence of residual K+, and calcination temperature.

Graphical AbstractNi substituted Co3O4 spinel oxide catalysts calcined at 500 °C gave good N2O decomposition reactivity. The catalytic activity decreased with increasing calcination temperature up to 1000 °C.Figure optionsDownload full-size imageDownload as PowerPoint slide