tOwing to the unique property of miniaturization and integration, microfluidic technology has beenmerged with many disciplines and exhibits its unique advantages in the corresponding areas. The prop-erty and performance of microfluidic system are tightly related to the property of inner surface ofmicrochannel. As an important inorganic nanomaterial, zinc oxide is often applied to the modificationof inner surface of microchannel as nanorods with low aspect ratio. However, zinc oxide nanorod onlycould provide limited contact area, which limits the application and performance of microfluidic system.So how to construct an efficient micro/nanostructured arrays with higher content and more contact areaof zinc oxide in limited microspace via a simple method become an urgent issue to be addressed in thefield of microfluidics. In this work, through microfluidic chemical method with the introduction of flu-orine, a novel ZnO/Zn(OH)F nanofiber arrays was successfully constructed on inner surface of confinedcapillary microchannels (CMs). In the photocatalytic application, the nanofiber array-based CMs couldalmost photodegrade methylene blue solution (5 mg L−1) as the residence time was 40 s; based on theunique advantage of micro/nanostructure, in the application of bio-separation, the nanofiber array-basedCMs could also absorb all the bovine hemoglobin (0.5 mg mL−1) as the residence time was 50 s and isolatehuman hemoglobin from human blood (500-fold diluted) effectively due to zinc-histidine coordinationand large contact area. So it has been demonstrated that the ZnO/Zn(OH)F nanofiber array-based CMswould be an ideal microfluidic system for versatile applications, such as photocatalysis and proteomics