Effective modification of Pd surfaces with TiO2 promoters using selective chemical vapor deposition and the effect on catalytic performance improvement

•TTIP readily decomposes at a much lower temperature in the presence of hydrogen.•Ti was selectively deposited on Pd active sites over a SiO2 support under a hydrogen atmosphere.•Pd surface is effectively modified by the selectively deposited Ti species.•Pd–Ti/SiO2 showed high ethylene selectivity than unmodified Pd/SiO2 in acetylene hydrogenation.

In this paper, we describe a novel method for selectively attaching TiO2 promoters on Pd surfaces in Pd/SiO2 catalysts using selective chemical vapor deposition (CVD). Ti was selectively deposited on Pd active sites over a SiO2 support under a hydrogen atmosphere when titanium tetraisopropoxide was used as a Ti precursor. The Pd–Ti/SiO2 catalyst modified by CVD exhibits approximately 1.8 times higher ethylene selectivity than the un-modified Pd/SiO2 catalyst in the selective hydrogenation of acetylene due to the effective geometric modification of the Pd surface, which is beneficial to ethylene selectivity, by the selectively deposited Ti species.

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