Operando investigations of strong metal-support interaction during catalysis

Pretreatment conditions dramatically alter the active surface of catalytic materials, influencing their performance. In a recent study, Monai et al. investigated the structural evolution of nickel nanoparticles (Ni NPs) supported on the reducible oxide TiO2 during the CO2 hydrogenation reaction. Operando electron microscopy showed the formation of TiOx bilayers during reductive pretreatments at 400 degrees C, while thicker TiOx overlayers were generated during more aggres-sive pretreatment at 600 degrees C. Under CO2 hydrogenation conditions, the TiOx bilayers receded, but small TiOx domains remained on the Ni/TiO2 materials that underwent pretreatment at 600 degrees C. The partially intact TiOx overlayer led to an extensive interface between Ni and TiOx, improving catalytic activity and selectivity toward C2+ products that are particularly desired in CO2 utilization schemes.