THE INFLUENCE OF SYNTHESIS CONDITIONS ON THE MORPHOLOGY OF ZnO NANORODS, OBTAINED BY CHEMICAL BATH DEPOSITION METHOD
Abstract
Nanostructured materials, particularly zinc oxide (ZnO), have attracted significant attention due to their wide range of applications, including piezoelectric devices, gas sensors, and photocatalysis. In particular, ZnO nanorods with their one-dimensional structure possess a high surface area and tunable morphology. This study investigates the effect of various synthesis conditions on the morphology of ZnO nanorods formed by chemical deposition. The impact of zinc oxide precursor concentration and auxiliary substances in the seeding solution, thermal treatment time, seed layer thickness, seed center diameter, and substrate type on the morphology of ZnO nanorods is examined. It is found that changing the concentration of hexamethylenetetramine (HMTA) has a minor effect on nanorod dimensions, while reducing the seeding solution concentration results in decreasing their length from 380±28 nm to 247±41 nm. Increasing the seed layer thickness promotes larger nanostructures and leads to an increase in average rod diameter from 86±12 nm to 102±13 nm and length from 356±29 nm to 391±46 nm. Reducing the seeding solution concentration decreases seed center diameters from 9±1 nm to 7±1 nm; conversely, reducing thermal treatment time increases them due to incomplete thermal decomposition of precursors. Horizontal positioning of substrates suppresses vertical growth due to active nucleation in bulk reaction solutions followed by deposition onto substrates; vertical positioning enhances crystal length instead. The obtained results provide valuable insights for directed synthesis of ZnO nanorods with specified characteristics for various applications
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