Impact of shock waves on the physical and chemical properties of aligned zinc oxide structures grown over metal-sheets

Abstract

Zinc oxide (ZnO) nanorods were developed on stainless steel (SS) sheets as well as glass substrates in two steps by adopting well-established two different chemical methods namely, spray pyrolysis and chemical bath deposition techniques. Then, the structures were exposed to dynamically generated shock waves in a home-built shock tunnel. All the as-grown and shock waves exposed structures were characterized with advanced analytical techniques. Surface morphology and structural studies reveal that the as-grown nanostructured films over the both SS and glass substrates possess nanorods-like surface morphology; however, they exhibited (101) and (001) orientations as predominant orientations, respectively. From micro Raman analysis, it is noticed that the nanorod structures grown on both surfaces have good phase purity and crystalline quality. On the other hand, the cathodoluminescence studies show that these hydrothermally grown ZnO nanorods possess a large number of native defects. Finally, the ZnO nanorods exposed to shock waves generated with a temperature and pressure of ca. ∼20,000 K and ∼6 MPa for a short duration of 2–3 ms exhibited superb sustainability in terms of surface morphology as well as crystalline quality, which is mainly attributed to the slantly overlapped morphology as well as the high melting temperature of ZnO nanorods.