Fig. 1. Microstructures of CoOOH NS and NR.

a, d SEM images, b, e TEM images, and c, f HRTEM images of CoOOH NS-M (a–c) and NR (d–f); g Schematic illustration of the sectioning of CoOOH NR for TEM observation; h, i TEM images of CoOOH NR after sectioning perpendicular (h) and parallel (i) to the basal surface. The NR in (h) disintegrated, and it should result from the shear stress in the sectioning procedure; j Basal plane size distribution of NS and NR. Standard errors were calculated from the standard deviations of the sizes of all the observed nanoparticles; k Thickness/height distribution of NS and NR. The particle sizes were based on measurements over an average of around 100 particles. The thicknesses of NS were measured by AFM, while other dimensions were measured by high-throughput SEM. Source data are provided as a Source Data file.