Synthesis of Noble Metal Nanoparticles Embedded in the Shell Layer of Core−Shell Poly(styrene-co-4-vinylpyridine) Micospheres and Their Application in Catalysis

The noble metal nanoparticles of Pd, Au, and Ag embedded in the shell layer of core−shell poly(styrene-co-4-vinylpyridine) micospheres were synthesized, and the catalytic activity of the shell-embedded Pd nanoparticles was investigated. To increase the accessible active site and therefore increase the catalytic activity of noble metal nanoparticles, the in situ synthesized noble metal nanoparticles are selectively immobilized in the outer shell layer of the core−shell poly(styrene-co-4-vinylpyridine) microspheres, which are synthesized by one-stage soap-free emulsion polymerization in water and contain a core of polystyrene and a coordinative shell of poly(4-vinylpyridine). It is found the Pd nanoparticles embedded in the shell layer of the core−shell micospheres are an efficient and easily reusable catalyst for Suzuki reactions performed in water.