Fig. 26. (a) Scheme of a nanoscale synchronous electrochemical/topographical map obtained by SECCM in voltammetric hopping mode by using a single channel nanopipette containing 100 mM H2SO4 and a GC support. The voltage was applied at the QRCE to control the WE potential (Eapp) while the WE current (isurf) was measured. The latter also served as a feedback signal for detecting meniscus-surface contact during the approach. Arrows show the movement of the nanopipette probe along the surface during scanning (inset, top-right). (b) Plots of (i) z-extension, (ii) Eapp and (iii) isurf during a ‘single hop’ at the AuNC substrate. Scan rate (v) = 10 V s−1 and data acquisition time (td) = 260 μs. Reproduced from ref. 217 with permission from the Royal Society of Chemistry © 2018.
