Hexagonally patterned arrays of well-aligned, regular ZnO nanopillars with controlled size, shape, and orientation were directly fabricated on zinc foils via a facile wet chemical approach with the assistance of monolayer colloidal crystals (MCC). Two kinds of templates that were derived from MCC, i.e., inverted MCC (IMCC) and connected MCC (CMCC), were employed as masks to define the growth…