In-situ studies on the synergistic effect of Pd-Mo bimetallic catalyst for anisole hydrodeoxygenation

Bimetallic catalyst is a major group of the heterogeneous catalysts which has been widely investigated for many important catalytic processes such as biomass upgrading. The synergistic effect between two transition metal of bimetallic catalyst plays a vital role to promote catalytic performance. In this work, the Pd-Mo bimetallic catalysts were investigated for the hydrodeoxygenation (HDO) of a biomass-derived molecule, anisole. The synergistic effect was confirmed in the Pd-Mo bimetallic catalyst. The correlated structure features of the Pd and Mo sites during catalysis have been revealed to understand the synergistic effect. It is found that the Mo species are partially reduced and cover around Pd nanoparticles. As the results, the crystalline status, redox properties, electron state and adsorption behaviors of Pd species are greatly influenced by Mo species. Moreover, the formation of Pd-Mo bond is directly observed by in-situ X-ray absorption spectrum. This work brings new insights to understand the structure origination for the synergistic effect in bimetallic catalyst.