In this work, we report the synthesis of ZnO nanowalls and nanocombs by the vapor–liquid–solid (VLS) method. ZnO nanocombs are applied in nanoscale functional devices such as nanocantilevers, UV nanolaser arrays, optical nanogratings, and nanopolarizer. These nanostructures are synthesized by the carbothermal reduction process between graphite and ZnO powder under high Zn vapor pressure. This work reports the possibility of synthesis of ZnO nanocombs by using the molar ratio ZnO:C (2:3) instead of the standard molar ratio (1:1) by the VLS method. The influence of the temperature variations on the geometrical shape of the grown nanostructures is discussed.