Low-temperature wafer-scale production of ZnO nanowire arrays

Homogeneous and dense arrays of ZnO nanowires were synthesized on silicon wafers (and many other substrates) using a mild solution process at 90°C. Uniform ZnO nanocrystals were deposited to act as seeds for subsequent hydrothermal nanowire growth, which yielded single-crystalline ZnO nanowires grown along the [0001] direction and oriented perpendicular to the water surface (see picture; scale bar = 1 μm). The photoluminescence and lasing behavior of the arrays has been studied as a function of annealing treatment conditions.