2.

Extended range of elements available for deposition in droplet confinement. Scanning electron micrographs and EDX analyses of elements from a wide range of standard electrode potentials indicated in the top right of each box (relative to the standard hydrogen electrode, SHE). Elements marked with an asterisk refer to the used electrode metal (substrate material) and are not part of the deposited structure. Bold indicates noncarbonaceous elements present in significant quantities that are neither the deposited element nor the substrate. Elements shaded in yellow contained traces of counterions or complexing elements, namely chloride for the utilized chloride salts. Note that Au and Pt could only be ejected by applying a negative potential, presumably due to the negatively charged chloride ions. Elements shaded in red allowed for a facile deposition, while elements shaded in purple necessitated a pH between 3 and 5 to enable a deposition of a structure with low oxygen content. Elements shaded in blue always contained a significant amount of oxygen. The prevalence of carbon does not correlate with the electrode potential of the deposited material.