Preparation and characterization of novel nanometer-scale platinum electrodes

Observation of the oxidation–reduction processes occurring at the nanoelectrode–solution interface demonstrates how electrochemical behavior depends upon nanoelectrode size. The use of a modified form of pulsed laser ablation as an improved method to synthesize nanometer-scaled electrode materials easily and consistently is reported. This method of fabrication enables platinum metal nanoparticles averaging 3 nm in diameter and approximately 5.0 × 10¹¹ particles/cm² to be deposited onto silicon substrates using optimum ablation parameters. A platinum silicide phase exists at the interface of the platinum and silicon as a result of the ablation process. Electrochemical results demonstrate the presence of a large number of isolated platinum particles (1.1 × 10⁷ particles/cm²), separated by an average edge to edge distance of 14 nm, which are electrochemically active nanoelectrodes.