Highly Crystalline K‐Intercalated Polymeric Carbon Nitride for Visible‐Light Photocatalytic Alkenes and Alkynes Deuterations

: In addition to the significance of photocatalytic hydrogen evolution, the utilization of the in situ generated H/D (deuterium) active species from water splitting for artificial photosynthesis of high value-added chemicals is very attractive and promising. Herein, photocatalytic water splitting technology is utilized to generate D-active species (i.e., Dad) that can be stabilized on anchored 2nd metal catalyst and are readily for tandem controllable deuterations of carbon-carbon multibonds to produce high value-added D-labeled chemicals/pharmaceuticals. A highly crystalline K cations intercalated polymeric carbon nitride (KPCN), rationally designed, and fabricated by a solid-template induced growth, is served as an ultraefficient photocatalyst, which shows a greater than 18-fold enhancement in the photocatalytic hydrogen evolution over the bulk PCN. The photocatalytic in situ generated D-species by superior KPCN are utilized for selective deuteration of a variety of alkenes and alkynes by anchored 2nd catalyst, Pd nanoparticles, to produce the corresponding D-labeled chemicals and pharmaceuticals with high yields and D-incorporation. This work highlights the great potential of developing photocatalytic water splitting technology for artificial photosynthesis of value-added chemicals instead of H2 evolution.