Boosting Suzuki coupling reaction via pore expanding and palladium-zinc alloying.

A palladium-zinc alloy nanoparticles decorated nitrogen-doped porous carbon catalyst (PdZn-NC) was synthesized and utilized for Suzuki coupling reaction. The alloying palladium (Pd) with zinc (Zn) and pore expanding are realized simultaneously. Density functional theory (DFT) calculations and experimental studies reveal that the alloying Pd with Zn can lower the energy barrier in Suzuki coupling reaction. Nitrogen adsorption-desorption measurements uncover that pore expansion caused by the zinc nitrate hexahydrate assisted calcination gives rise to the multiplication of mesopore with a pore diameter of 6 nm, which facilitates mass transfer during the reaction. As a result, the alloying Pd with Zn and pore expanding together endow PdZn-NC with excellent catalytic activity. PdZn-NC demonstrates exceptional catalytic activity and stability in Suzuki coupling reaction. A high biphenyl yield of 97.7 % within 40 min and stable reusability of 93.3 % yield after five reuse cycles can be achieved. This work not only offers a viable method for Suzuki coupling reaction, but also provides insights for designing new catalysts toward Suzuki coupling reaction.