Degradation of organic dye using ZnO nanorods based continuous flow water purifier

Zinc oxide (ZnO) is a common semiconductor material uses in waste water treatment. However, utilizing of ZnO particles could be easily drained away by water and charged into the water system during the photocatalytic treatment. This could result of forming secondary pollution in the water system. Hence, it is necessity to grow ZnO nanorods on polyethylene terephthalate (PET) fiber to minimize the above mentioned problem. In this work, ZnO nanorods were grown on the flexible PET fiber in large quantity using a sol–gel method at low temperature (90 °C). A layer of 1-dodacanethiol polymer was per-coated on the PET fiber to improve the deposition of ZnO seed layer prior to the growth of ZnO nanorods. The PET fiber was covered with high areal density of ZnO nanorods (10.2 ± 0.8 NRs/μm²). Subsequently, this PET fiber was inserted into a glass tube for the setup of continuous flow water purifier. The photocatalytic study for degradation of Rhodamine B solution using this setup indicated that the reaction followed 1st order kinetic with rate constant of 1.28 h⁻¹. The ZnO nanorods were still intact with the fiber after the photocatalytic study. Thus, it is possible to upscale this setup as water purifier to purify the water system.