Removing polyvinylpyrrolidone from catalytic Pt nanoparticles without modification of superficial order.

Herein, we report a simple methodology for cleaning Pt nanoparticles, prepared by a colloidal synthesis and coated with polyvinylpyrrolidone, without loss of crystalline surface structure. To prove the removal of the polyvinylpirrolidone from a Pt surface without disturbing the superficial order, a cleaning method using a solution of H(2)O(2)/H(2)SO(4) was tested successfully for a Pt(111) single-crystal electrode. The decontamination method was then tested for two different types of nanoparticles by mixing the suspension of nanoparticles with H(2)O(2)/H(2)SO(4) and subsequent centrifugation. The resulting voltammetric profiles of platinum particles synthesized by the colloidal method employing PVP show a marked presence of the adsorption-state characteristic of (111) ordered surface domains. The presence of the well-ordered domains present on the surface of the nanoparticles was confirmed by using the irreversible adsorption of bismuth, tellurium and germanium.