Hydrogen spillover is a well-known phenomenon in heterogeneous catalysis; it involves H₂ cleavage on an active metal followed by the migration of dissociated H species over an ‘inert’ support^1,2,3,4,5. Although catalytic hydrogenation using the spilled H species, namely, spillover hydrogenation, has long been proposed, very limited knowledge has been obtained about what kind of support structure is required to achieve spillover hydrogenation^1,5. By dispersing Pd atoms onto Cu nanomaterials with different exposed facets, Cu(111) and Cu(100), we demonstrate in this work that while the hydrogen spillover from Pd to Cu is facet independent, the spillover hydrogenation only occurs on Pd₁/Cu(100), where the hydrogen atoms spilled from Pd are readily utilized for the semi-hydrogenation of alkynes. This work thus helps to create an effective method for fabricating cost-effective nanocatalysts with an extremely low Pd loading, at the level of 50 ppm, toward the semi-hydrogenation of a broad range of alkynes with extremely high activity and selectivity.

氢溢出是非均相催化中众所周知的现象。它涉及在活性金属上进行H ₂裂解，然后在“惰性”载体^1,2,3,4,5上解离的H物种迁移。尽管长期以来一直提出使用溢出的H物种进行催化加氢，即溢出加氢，但对于实现溢出加氢^1,5需要哪种载体结构的知识非常有限。通过将Pd原子分散到具有不同暴露面Cu（111）和Cu（100）的Cu纳米材料上，我们证明了在这项工作中，尽管从Pd到Cu的氢外溢是独立的，但溢出氢化仅发生在Pd _1上/ Cu（100），其中从Pd溢出的氢原子很容易用于炔烃的半氢化反应。因此，这项工作有助于创造一种有效的方法，以50％的Pd含量极低的Pd负载成本效益地制造纳米催化剂，以实现具有极高活性和选择性的多种炔烃的半氢化反应。