Influence of the diffuse double layer on steady-state voltammetry

► Comprehensive description of how the diffuse double layer affects Faradaic current. ► 'Levich exclusion' of the reactant species by electrode charge can limit current. ► Tunnelling can overcome both unfavourable Levich exclusion and Frumkin corrections. ► Nanoelectrodes exhibit voltammetry altered by an unscreened electric field.