Surface coverage and size effects on electrochemical oxidation of uniform gold nanoparticles

• Diameter (4~9 nm) and inter-particle spacing (30~60 nm) of Au nanoparticles are finely tuned by using diblock copolymers
• The arrays of Au nanoparticle have neither adlayer nor aggregation.
• Coverage is more influential effect than diameter to electrochemical oxidation of evenly spaced nanoparticles.

We investigated the electrooxidative dissolution of uniformly distributed Au nanoparticles (NPs) without an extra adhesion layer or capping agent. Diblock copolymer micelles were exploited to fabricate the arrays of Au NPs where not only diameter of the particles but also inter-particle spacing, and thus coverage were finely controlled. The peak potential for electrochemical oxidation shifted greater as a function of coverage of NPs than the size.