A graphdiyne-based carbon material for electroless deposition and stabilization of sub-nanometric Pd catalysts with extremely high catalytic activity

The development of sub-nanometric metal particles (<1 nm) as advanced heterogeneous catalysts has received considerable interest due to their outstanding catalytic performance, while the synthesis and stabilization of sub-nanometric catalysts (SNCs) without using additional surface capping agents remains a challenge. Herein, we report the synthesis of novel three-dimensional pyrenyl graphdiyne (Pyr-GDY) ultrafine nanofibers (3-10 nm), which can serve as an ideal substrate for electroless deposition and stabilization of Pd SNCs through the terminal uncoupled acetenyl groups in Pyr-GDY, with an average Pd particle size of only 0.83 nm. The as-synthesized Pd/Pyr-GDY composite shows extremely high catalytic activities for the reduction of nitroarenes to arylamines and Suzuki coupling reactions, 300 and 25 times higher than those of commercial Pd/C, respectively. The outstanding catalytic performance can be ascribed to the sub-nanometric Pd particles with a clean surface, and the unique three-dimensional network structure of Pyr-GDY, being favorable for rapid mass transfer. Our result provides an ideal carbon material for electroless deposition and stabilization of other SNCs with a clean surface, which will display outstanding catalytic activity for various catalytic reactions.