Growth of wurtzite ZnO nanorods using different capping agents: Characterization, morphology, and investigation the catalytic activity in some oxindoles and indolyl organics

ZnO nanorods have been prepared through chemical deposition of Zn(OAc)2.2H2O by employing different capping agents, (PEG, MW=2000 and PEG, MW=5000). The fabricated catalyst was characterized by scanning electron microscope (SEM) images and XRD pattern. The results show the one dimensional growth of ZnO nanorods. The results show that capping agents can control the shape and growth of nanosized crystals. The vertically aligned ZnO was fabricated by PEG 2000, but PEG 5000 changes the ZnO nanorods to elbow shape. The synthesized nanorodes have been utilized as highly efficient catalyst to promote some onepot multicomponent reactions (MCRs) of indoles consist of symmetrical and unsymmetrical 3,3-di(indolyl)indoline-2-ones and tris(indolyl)methanes synthesis under mild reaction conditions, respectively. Comparison of the catalytic power of these two kinds of synthetic ZnO NRs (2000 5000) has also been investigated. Importantly, the catalysts can be recovered from the reaction media and reused for four runs without any activity loss.