Integration of Bimetallic Electronic Synergy with Oxide Site Isolation Improves the Selective Hydrogenation of Acetylene.

Semi-hydrogenation of acetylene to ethylene is an important process to purify ethylene streams in industry. However, among current approaches reported in the literature, high ethylene selectivity has been generally achieved at the expense of activity. Herein, we show that a Ga O coating of Ag@Pd core-shell bimetallic nanoparticle catalysts, allows improvement of the ethylene selectivity to a much greater extent than the coating of monometallic Pd nanoparticles, while preserving a remarkable intrinsic activity, approximately 50 times higher than the benchmark catalyst of Pd Ag single-atom alloys (SAAs). Importantly, the resulting catalyst also shows excellent long-term stability, by suppressing coke formation efficiently. Spectroscopic characterization reveals that weakened ethylene adsorption by bimetallic electronic synergy, and oxide site isolation are both essential for the high ethylene selectivity and high-coking resistance. H-D exchange measurements further show that the Ga O -coated Ag@Pd catalyst possesses a much higher activity of H activation than that of Pd Ag SAAs, thus boosting the hydrogenation activity at the same time.