Effect of ZnO core electrodeposition conditions on electrochemical and photocatalytic properties of polypyrrole-graphene oxide shelled nanoarrays

• Published in: Applied surface science 2017-01, Vol.392, p.801-809
• Main Authors: Pruna, A., Shao, Q., Kamruzzaman, M., Li, Y.Y., Zapien, J.A., Pullini, D., Busquets Mataix, D., Ruotolo, A.
• Format: Article
• Language: English
• Subjects: Core/shell; Deposition; Electrodeposition; Graphene; Graphene oxide; Morphology; Nanorod; Nanostructure; Oxides; Photocatalysis; Polypyrrole; Pyramid; Zinc oxide; ZnO
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2016.09.122

•ZnO/PPy-GO core/shell nanoarrays were obtained by 2-step electrochemical approach.•Crystalline structure and orientation of ZnO nanorods improved with deposition potential.•Morphology of ZnO changed from nanorods to pyramidal shape with increased deposition duration.•Electroactivity of core/shell is improved with crystallinity of ZnO for nanorod morphology.•Photocatalytic activity of core/shell NAs is improved for nanorod core morphology than pyramid one. Novel hybrid core-shell nanoarchitectures were fabricated by a simple two-step electrochemical approach: first ZnO nanorod core was electrodeposited from Zn(NO3)2 solution; further, the core nanoarray was coated with a shell based on polypyrrole hybridized with graphene oxide by electropolymerization. The properties of the core/shell nanoarchitectures were studied as a function of the core properties induced by electrodeposition parameters. The ZnO nanostructures showed improved crystallinity and c-axis preferred orientation with increasing cathodic deposition potential while the increased deposition duration resulted in a morphology transition from nanorod to pyramidal shape. The electrochemical activity of the core/shell arrays was found to increase with the deposition potential of ZnO core but decreased when morphology changed from nanorod to pyramid shape. The photocatalytic results showed improved activity for the core/hybrid shell nanoarrays with respect to ZnO and ZnO/PPy ones. The degradation rate for methylene blue decreased with prolonged deposition duration of the core. The obtained results highlight the importance of electrochemical tuning of ZnO-based core/shell nanoarrays for improved performance in electrochemical and photocatalytic applications.