A comparison of optical properties of ZnO nanorods and ZnO nanotips for improving light absorption in rGO/ZnO nanostrctures en en In this study, two types of ZnO nanostructures (ZnO nanotips and ZnO nanorods) were synthesized through a chemical bath deposition (CBD) method. These two structures were then compared by optical and structural analyses. The result showed the significant effect of ammonia concentration and the preferential etchings along the c axis on the formation of ZnO nanotips (NTs). To improve the absorption, nanostructures were optimized by reflectance analysis. To enhance the optical properties of the optimized sample, reduced graphene oxide (rGO) layers were transferred on the ZnO NTs surface by the electrophoretic deposition (EPD) method. The deposition of rGO layers on ZnO NTs can increment the optical absorption over a wide range of frequencies. The reflectance results showed enhanced adsorption capacity in the case of rGO/ZnO NTs. 74 76 Parisa Fallahazad Department of Semiconductors Materials and Energy Research Center Iran parisa.fallahazad@gmail.com Mahsa Sharifi Department of Semiconductors Materials and Energy Research Center Iran info@jourcc.com Nima Naderi Department of Semiconductors Materials and Energy Research Center Iran info@jourcc.com Mohamad Javad Eshraghi Department of Semiconductors Materials and Energy Research Center Iran info@jourcc.com Reduced graphene oxide Chemical bath deposition ZnO nanorods ZnO nanotips Electrophoretic deposition Article1.pdf [1] S.M. Mostafavi, Enhancement of mechanical performance of polymer nano-composites using ZnO nanoparticles, Chemistry 39 (2015) 2269-2278. ## [2] V.V. Ursaki, O. Lupan, I.M. Tiginyanu, G. Chai, L. 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