Figure 3.

Single-particle measurement of dynamic electrochemical tuning in the cathodic range (0 to −800 mV). (a) Electrochemical potential of the working electrode relative to the reference electrode as a function of time. Sweep rate: 10 mV/s. (b) Scattering spectra under dynamic potential control. The fitted resonance energy, E_Res (solid white line), and full width at half-maximum, Γ (dotted white lines), are superimposed. (c) Reversible, cyclic E_Res response as a function of potential U shown as mean with standard error for three consecutive cycles. (d) Average Γ over three cycles as a function of potential. (e) Mie–Drude model simulations, and the number of electrons transferred from the conductive substrate to the nanoparticle is calculated. Error bars indicate propagated standard error in E_Res. Arrows indicate the scanning directions of the applied potential.