This paper reports the metalorganic vapor-phase epitaxial growth of vertically aligned ZnO nanorods on Al2O3(00·1) substrates at 400°C without using any metal catalysts. The nanorods have uniform diameters (25 nm), lengths, and densities, and are epitaxially grown with homogeneous in-plane alignment and c-axis orientation. Photoluminescence (PL) measurements show strong and narrow excitonic emission and extremely weak deep level emission, indicating high optical quality. The nanorods are grown using a low-pressure MOVPE system with diethylzinc (DEZn) and oxygen as reactants. The growth process involves the formation of ZnO buffer layers at low temperatures. The crystal structure was analyzed using XRD, showing a narrow full width at half maximum (FWHM) and six-fold symmetry in azimuthal scans, confirming in-plane alignment and c-axis orientation. FE-SEM images reveal uniform thickness and length distributions, as well as hexagon-shaped pyramids at the ends of the nanorods, suggesting a non-catalytic growth mechanism. The optical properties of the nanorods were investigated using PL spectroscopy, showing a dominant free exciton peak at 3.29 eV with a narrow FWHM, indicating no quantum confinement effect. The results demonstrate that MOVPE can produce high-quality ZnO nanorods with excellent optical and structural properties, suitable for various electronic and photonic applications. This method offers advantages such as large area growth and precise control of doping and thickness. The study highlights the potential of MOVPE for the fabrication of one-dimensional nanorods without the need for metal catalysts.This paper reports the metalorganic vapor-phase epitaxial growth of vertically aligned ZnO nanorods on Al2O3(00·1) substrates at 400°C without using any metal catalysts. The nanorods have uniform diameters (25 nm), lengths, and densities, and are epitaxially grown with homogeneous in-plane alignment and c-axis orientation. Photoluminescence (PL) measurements show strong and narrow excitonic emission and extremely weak deep level emission, indicating high optical quality. The nanorods are grown using a low-pressure MOVPE system with diethylzinc (DEZn) and oxygen as reactants. The growth process involves the formation of ZnO buffer layers at low temperatures. The crystal structure was analyzed using XRD, showing a narrow full width at half maximum (FWHM) and six-fold symmetry in azimuthal scans, confirming in-plane alignment and c-axis orientation. FE-SEM images reveal uniform thickness and length distributions, as well as hexagon-shaped pyramids at the ends of the nanorods, suggesting a non-catalytic growth mechanism. The optical properties of the nanorods were investigated using PL spectroscopy, showing a dominant free exciton peak at 3.29 eV with a narrow FWHM, indicating no quantum confinement effect. The results demonstrate that MOVPE can produce high-quality ZnO nanorods with excellent optical and structural properties, suitable for various electronic and photonic applications. This method offers advantages such as large area growth and precise control of doping and thickness. The study highlights the potential of MOVPE for the fabrication of one-dimensional nanorods without the need for metal catalysts.