Graphdiyne@Janus Magnetite for Photocatalytic Nitrogen Fixation.

A highly active graphdiyne heterojunction with highly efficient photocatalysis is designed and fabricated. This catalyst demonstrates transformative properties on photocatalysis for ammonia synthesis. Such excellent properties are reigned from graphdiyne incorporating Fe site-specific magnetite resulting in a valence state transition within the catalyst. Our results show the strong advantages of graphdiyne in effectively regulating magnetite activity and coordination environments and also indicate that magnetite can selectively form two different valence tetrahedral coordination Fe and octahedral coordination Fe. The catalysts show remarkable catalytic performance for ammonia synthesis by photocatalysis, indicating transformative photocatalytic activity with an ammonia yield (Y NH 3 ) of unprecedented level of 1762.35±153.71 μmol h-1  gcat. -1 (the highest Y NH 3 could reach up to 1916.06 μmol h-1  gcat. -1 ). This work makes full use of the structural and property features of graphdiyne and opens up a new direction for photocatalysis in the field of catalysis.