Shape-controlled synthesis and application in surface-enhanced Raman scattering of novel palladium nanoparticles

Palladium nanoparticles (PdNPs), as a platinum substitute, have opened many new opportunities for future catalytic applications, especially in fuel cell reactions, because of its comparable catalytic properties. In the present study, a simple and “green” procedure to the synthesis of PdNPs with cauliflower-like and polyhedron-like shapes is demonstrated. The novel PdNPs were prepared by the reduction of palladium chloride with ascorbic acid in the presence of chitosan served as a capping agent, whose shapes can be effectively controlled by varying reaction temperatures. Surface-enhanced Raman scattering (SERS) investigation demonstrated that the more irregular PdNPs have the stronger SERS activities. We believe that the PdNPs with unique shapes may find practical applications for electronics, photonics, fuel cells, and biofuel cells.