Figure 2. Fabrication of monodisperse ZnO₂ nanoparticles via the Leidenfrost charge-driven chemistry.

(a) The snapshots visualize the Leidenfrost chemistry in a Petri dish and eruption of the formed clusters, specified by the black arrows (extracted from Supplementary Movie 3 based on the 10 mM experiment but at a larger volume of 50 ml); (b) SEM image depicting morphology of the synthesized monodisperse ZnO₂ nanoparticles obtained from the 10 mM experiment (scale bar, 5 μm); (c) Particle size distribution of the ZnO₂ nanoparticles; (d) XRD pattern of the synthesized ZnO₂ nanoparticles; (e) The snapshots visualize the Leidenfrost chemistry in a beaker (extracted from Supplementary Movie 5) (scale bar, 1 cm); SEM images of the synthesized monodisperse ZnO₂ nanoparticles obtained from the 50 mM experiment: size-tailored self-assembled monodisperse nanoclusters in different average particle sizes of (f) 126 nm, (g) ∼70 nm (scale bars for f,g are 1 μm), (h) ∼220 nm, (i) ∼680 nm (depending on the precursor zinc acetate solution concentration) (scale bars 5 μm (h,i)).