Enhanced electrocatalytic activity and stability of Pd-based bimetallic icosahedral nanoparticles towards alcohol oxidation reactions

Modulating components and surface structure of Pd-based nanomaterials were efficient strategies to improve electro-catalytic activity. Bimetallic Pd-based nano-catalysts with core-shell or alloy structure are reported to be promising for fuel cell reactions. In this work, we have successfully constructed PdCu@Pd core-shell icosahedral nano-catalysts via the hydrothermal method. Based on this method, we have successfully synthesized alloyed PdPt icosahedrons, PdAg icosahedrons, and monometallic Pd icosahedrons. Among all nanoparticles as prepared, PdCu@Pd core-shell icosahedral nano-catalyst exhibits the highest mass activity to ethylene glycol oxidation reaction (EGOR) as 7.4 A mg(-1), which is 7.4 times higher than that of commercial Pd/C (1.0 A mg(-1)). In addition, its mass activity for glycerol oxidation reaction (GOR) is 6.3 A mg(-1), which is 6.5 times higher than that of commercial Pd/C (0.96 A mg(-1)). In the test of stability, PdCu@Pd core-shell icosahedral nano -catalyst keeps the highest current density throughout the time domain. The enhanced electro-catalytic performance can mainly attribute to the modification of electronic gener-ated from strain between Pd shell and PdCu core as well as defect from twinned structure.