Polyoxometalate‐Based Metal–Organic Framework as Molecular Sieve for Highly Selective Semi‐Hydrogenation of Acetylene on Isolated Single Pd Atom Sites

and create dynamic confinement regions, which preferentially release the produced ethylene. Besides, at the Pd site, the over-hydrogenation of ethylene exhibits a higher reaction energy barrier than the semi-hydrogenation of acetylene. The combined advantages of POMOF and single Pd atom provides an effective approach for the regulation of semi-hydrogenation selectivity.