Nanoscale characteristics of electrochemical systems

This chapter presents a tutorial introduction to nanoscale electrochemistry, addressing general underlying principles, theoretical approaches and practical considerations that are essential for studying nanoelectrochemical systems. We begin with an account of fundamental physical length scales in electrochemistry, with an emphasis on phenomena that make nanoelectrochemical measurements and their interpretation qualitatively distinct from those at larger scales. This includes modified diffusional phenomena, the increased relative significance of the electrical double layer, stochastic treatment of single entity events, unique surface atomic arrangements, nanoconfinement, quantum effects, and altered optical properties. We then give an overview of the fundamental theory of nanoscale electrochemistry, describing how standard theoretical and modeling approaches must be modified or refined to account for characteristic behavior at such small length scales. Finally, we give a general instructive account of some of the key practical challenges that are commonly encountered when performing experimental measurements on nanoelectrochemical systems.