Synergizing Pd 1 Sb 2 Site with Neighboring Near-Surface Pd Site to Break the Trade-Off between Selectivity and Activity of Alkyne Semihydrogenation

作者：Xiaohu Ge, Yundao Jing, Wenjie Wang, Yueqiang Cao, Jing Zhang, Gang Qian, Hao Jiang, Xinggui Zhou, De Chen, Weikang Yuan, Xuezhi Duan · 发表于：Journal of the American Chemical Society · 年份：2025 · DOI：10.1021/jacs.5c08564 · 被引用次数：13 · 研究领域：Asymmetric Hydrogenation and Catalysis、Carbon dioxide utilization in catalysis、Catalytic Processes in Materials Science

Catalytic hydrogenation of trace alkynes in excess alkenes is essential for producing polymer-grade olefins from steam cracking and alkane dehydrogenation, but achieving high selectivity without sacrificing activity remains a significant challenge. Herein, we report a catalyst design that synergistically integrates computationally proposed surface Pd 1 Sb 2 trimer sites with near-surface Pd sites (Pd ns ) on the P 6 3 / mmc PdSb intermetallic catalyst to achieve the semihydrogenation of alkynes with both high activity and selectivity. Alkynes can be readily activated through strong σ-bonding on the Pd 1 Sb 2 trimer sites, whereas alkenes are only weakly adsorbed via π-interactions due to their matched electronic structures and spatial configurations. Moreover, the neighboring Pd ns cooperates with the Pd 1 Sb 2 sites to achieve spontaneous dissociation of H 2 for subsequent hydrogenation. Consequently, the fabricated PdSb intermetallic catalyst exhibits ethylene and propylene selectivities of 96.50% and 98.65%, respectively, at nearly complete conversions of acetylene and propyne, under industrially relevant conditions, outperforming state-of-the-art catalysts. This study demonstrates a promising strategy that synergizes near-surface and surface ensemble sites to spatially and energetically match with the target reaction pathway, enabling the overcoming of the trade-off between activity and selectivity in hydrogenation.