Ultrahigh Single Au Atoms Loaded Porous Aromatic Frameworks for Enhanced Photocatalytic Hydrogen Evolution.

Supported single-atom catalysts (SACs) are promising in heterogeneous catalysis because of their atom economy, unusual transformations, and mechanistic clarity. The metal SAs loading, however, limits the catalytic efficiency. Herein, an in situ pre-metallated monomer-based preparation strategy is shown to achieve ultrahigh Au SAs loading in catalyst formations. The polymerization of single-atom loaded monomers yield a new porous aromatic framework (PAF-164) with Au SAs loading up to a record high 45.3 wt.%. SACs of Au-PAFs exhibit excellent photocatalytic activity in hydrogen (H) evolution, and the H evolution rate of Au-SAs-PAF-164 can reach 4.82 mmol g h with great recyclability.