Single Ag Nanoparticle Electro-oxidation: Potential-Dependent Current Traces and Potential-Independent Electron Transfer Kinetic.

Potential-dependent current traces were first observed for the same sized nanoparticles (NPs) during the dynamic electro-oxidation process of single AgNPs. In this work, we demonstrated that the motion trajectories of NPs, coupled with electrochemical kinetics parameters, qualitatively predicted from the series of the experimentally observed current traces obtained single AgNPs collision behaviors. Based on the Poisson-Boltzmann equation for a general electrochemical reaction, a rate constant of Ag oxidation could be further estimated to be 1 × 10-6 mol·cm-2·s-1 for electron transfer between AgNPs and the Au electrode by comparing the experimental results. Our method provided a meaningful attempt to test electron transfer kinetics and motion behaviors of single NPs using the high-resolution electrochemical signal.