Effects of Instrumental Filters on Electrochemical Measurement of Single-Nanoparticle Collision Dynamics

We discuss herein present-day instrumental limitations to the electrochemical measurement of fast processes occurring at the single-entity scale. We focus on the effect of filters on potentiostatic experiments in which the monitored current results from partial oxidations of an individual Ag nanoparticle undergoing repeated high-frequency collisions with an electrode. From analysis of the resulting peak-shaped current-time events, we conclude that the average timescale of a single Ag nanoparticle/electrode collision is too short to resolve at the temporal limitations of current instrumentation. These findings are consistent with previously reported random walk model that predicts nanoparticle/electrode interactions at nanosecond timescales.