Gelatin-Pyrolyzed Mesoporous N-Doped Carbon Supported Pd As High-Performance Catalysts For Aqueous Heck Reactions

Nitrogen-doped mesoporous carbon-supported Pd (Pd@N-C) catalysts were prepared by pyrolyzing gelatin/templates/PdCl2 hydrogels under N-2 atmosphere at 800 degrees C. Using poly (ethylene glycol) block poly (propylene glycol) block poly (ethylene glycol) (P123) as soft template and/or colloidal SiO2 as hard templates can significantly improve the Brunauer-Emmett-Teller (BET) surface area, porous structure, and pore volumes of the resultant Pd@N-C catalysts. Pd nanoparticles sized from 10-20 nm can be well immobilized on the mesoporous carbon matrix by one-pot carbonization (OC) and/or solution impregnation (SI) process. The resultant Pd@N-C catalysts with best physical properties was found in the case of Pd@N-C-SiO2-OC (1/1), exhibiting high BET surface area of 695.2 m(2)/g, large pore volume of 1.05 cm(3)/g, high mesoporous centered at 3.7 and 9.1 nm, rich N content of 7.7%, and high thermal stability with beginning decomposition temperature above 500 degrees C. It showed excellent activities for aqueous Heck coupling reactions of aromatic iodides and butyl acrylates and can be recycled for at least eight times with yield still higher than 80%. This work might facilitate a versatile platform for green and functional utilization of nature-rich biopolymer of gelatin.