Adsorption of BiIII on Pt nanoparticles leading to the enhanced electrocatalysis of glucose oxidation

The nanocomposites of Bi-III/Pt nanoparticles (PtNPs) were prepared using an operationally simple method, in which Bi-III spontaneously adsorbed onto the surface of PtNPs to form a submonolayer by the strong interactions between Bi-III and Pt. The adsorption of Bi-III on PtNPs was confirmed by electrochemical studies. Without PtNPs, Bi-III did not adsorb directly on the surface of glassy carbon electrode. The specific chemistry resulted in high electrocatalysis performance of the obtained nanocomposites toward glucose oxidation compared with PtNPs alone because of the dual effects of Bi(III). On the one hand, Bi tends to bind OH- from alkaline solution and then to share it with the adjacent Pt atom. This binding leads to an increase in number of hydroxylated Pt centers, which are the active species for the electrochemical oxidation of glucose. On the other hand, Bi acts as a binder to cross-link PtNPs and to immobilize them on the surface of glassy carbon electrode. The fabricated Bi-III/PtNP nanocomposites may have the potential applications in the areas of electrocatalysis or electroanalysis.