Enhanced Dry Reforming of Methane Catalysis by Ni at Heterointerfaces between Thin MgAlO_x and Bulk ZrO₂

The catalytic performance of supported metals is greatly influenced by the interaction with the support material. The role of the support becomes even more important when dealing with metal nanoparticles and high reaction temperatures. Herein, we show that interfacial sites between two metal oxides, MgAlO_x and ZrO₂ can bestow high stability as well as enhanced reactivity to nickel (Ni) nanoparticles. We use the MgAlO_x as thin oxides on an underlying bulk ZrO₂. We demonstrate the effect of the metal-support interactions (MSI) in different support locations on the performance in dry reforming of methane (DRM). We find that the rate of DRM catalysis produces a concave-down trend with respect to Ni loading with a maximum at ~0.8–1.1 % wt Ni. Measuring the Ni2p_3/2 binding energy (BE), we find a similar concave-down trend whereas for the Mg2p BE we find a concave-up trend with respect to the Ni loading both with the maximum and minimum centered at 0.8–1.1 % wt Ni, respectively. These trends were correlated with the stability of Ni calculated by DFT. Overall, our results suggest that heterointerfacial sites can be used to tailor moderate MSI, which can be used in the design of DRM catalyst with significantly increased activity and high stability.