Visible-light driven photocatalytic performance of eco-friendly cobalt-doped ZnO nanoarrays: Influence of morphology, cobalt doping, and photocatalytic efficiency

[Display omitted] •Co2+-doped ZnO nanoarrays was first grown on substrate and used as photocatalyst.•Co2+ was doped to improve the photocatalytic activity under visible-light induction.•Co2+-doped ZnO efficiently remove organic pollutants for environmental protection. In order to remove the organic pollution from water environment, Co2+-doped ZnO nanoarray photocatalyst was prepared through a hydrothermal process. The influences of Co2+ doping amount and hydrothermal temperature on the nanostructure and photocatalytic performance of Co2+-doped ZnO nanoarray were discussed in detail. The standard ZnO structure and nanoarray morphology of Co2+-doped ZnO samples were achieved and the absorption of visible light was also realized through Co2+ doping. The 2% Co2+-doped ZnO nanoarray prepared at 95 °C exhibited excellent photocatalytic activity and could degrade 96% of methylene blue solution within 120 min under visible light. Furthermore, the as-prepared 2% Co2+-doped ZnO nanoarray still maintained 91% for removal rate after 3 cycles of photocatalytic degradation, showed good photocatalytic activity and recyclability. All results indicate that ZnO nanoarray with Co2+ doping has a potential application in visible light photocatalysis for environmental protection and pollution control.