Electrochemical sizing of hemispherical microdroplets immobilized as regular arrays on partially blocked electrodes

The size of microdroplets of dodecane of approximately 5 μm diameter immobilised on a regular array of hydrophobic polymer blocks of a partially blocked electrode is determined by comparison of a simple electrochemical procedure with simulations. The electrochemical procedure is based on a simple Cottrellian-like potential-step experiment, where the current response is monitored as a function of time. Excellent agreement is found between theory and experiment thus giving physical support for the expected transition in diffusion layer shape and size.