High-Performance PdZn and PdAg Catalytic Films for the Semihydrogenation of 2-Methyl-3-Butyn-2-ol in a Flow Microreactor

Synthesizing an active, selective, and stable catalytic coating is a challenging task for the semihydrogenation of alkenols in a flow microreactor, which offers a potentially effective strategy for alkenol production in fine organic synthesis. In this study, PdMe/TiO2 (Me = Zn, Ag) catalytic films were prepared using a simple and efficient template sol-gel method and used in the semihydrogenation of 2-methyl-3-butyn-2-ol. The prepared bimetallic PdMe/TiO2 (Me = Zn, Ag) catalytic films demonstrated high catalytic selectivity due to the formation of PdZn and PdAg alloy nanoparticles (NPs). The surface area of the PdAg active site changes under the reaction conditions. The PdZn film demonstrates better catalytic efficiency. Doping the support with zinc increases the selectivity and stability of the films. Analysis of X-ray photoelectron spectra showed that the zinc-doped PdZn/Ti0.8Zn0.2O1.8 film has a higher concentration of PdZn active sites and better oxidation stability than PdZn/TiO2. The PdAg/TiO2 and PdZn/Ti0.8Zn0.2O1.8 catalytic films demonstrated high stability during long-term testing.

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