Electrochemical characters and structure changes of electrochemically treated Pt nanoparticles

In this paper, the surface and electrochemical characters of the Pt/CNT electrode before and after voltammetric cyclings were studied using high resolution transmission electron microscopy imaging (HRTEM), X-ray photon electron spectroscopy (XPS) and cyclic voltammetry measurements of CO and methanol oxidation. It was found that Pt nanoparticles were not stable and formed the linked and agglomerated structures. The changes of the crystallites led to the peak multiplicity, the negative shift of CO oxidation peaks, and the increase of the current density of methanol oxidation. We considered the specific activities were due to the increases of oxygen species and defect sites on Pt.