In situ electro-deposition of Pt micro-nano clusters on the surface of {[PMo12O40]3-/PAMAM}n multilayer composite films and their electrocatalytic activities regarding methanol oxidation.

The {PMo(12)O(40)/PAMAM}(n) multilayer films are prepared by LBL electrostatic assembly technique, and their uniform and homogeneous traits have been verified by cyclic voltammetry. The {PMo(12)O(40)/PAMAM}(n) multilayer films with PAMAM as the outmost layer, having an open structure and exhibiting good penetrability for the solvent molecules at low pH, are used as matrices for electro-deposition of Pt micro-nano clusters in situ. X-ray photoelectron spectroscopy (XPS) analysis and field emission scanning electron microscope (FE-SEM) characterization show that the unique Pt micro-nano clusters with flower-like structure have been immobilized on the surface of {PMo(12)O(40)/PAMAM}(n) multilayer films. The morphologies of Pt micro-nano clusters are influenced by electro-deposition conditions such as deposition potential, deposition time, and the number of layers of {PMo(12)O(40)/PAMAM}(n) multilayer films. Pt(-clusters)-{PMo(12)/PAMAM}(3) composite films demonstrate good electrocatalytic activities regarding methanol oxidation and improved tolerance of CO.