Controllable coating of zinc oxide on protein-based fibers/fabrics for superior antibacterial performance preserving wearable abilities

• Atomic layer deposition technic was used to modify protein-based fibers. • ZnO nano film was controllably deposited on the surface of silk fabrics. • Modified silk had antibacterial properties while preserving favorable properties. As a natural protein resource, silk has been favored for thousands of years due to remarkable properties and the lustrous appearance. The broaden use of natural silk promotes it to become a high-tech fiber, which is undesirably hindered by the high hygroscopicity that provides conditions for bacterial growth thus accelerates the corrosion of silk. Functional surface modification can pose as compensation, but traditional nanoscale coating approaches come at the expense of inherent properties. In this work, ultrathin zinc oxide (ZnO) was uniformly deposited on silk fabrics in nanoscale using the atomic layer deposition (ALD) strategy. Different layers of ZnO were deposited by controlling the deposition cycles in the ALD process to evaluate the influences in antibacterial performances. The ZnO coated silk fabrics showed neglectable differences in morphologies compared with the raw silk fabric while manifesting excellent antibacterial properties against E. coli and S. aureus . The ZnO layer had insignificant influence on mechanical and air permeable properties, which guaranteed the wearable properties of silk fabrics. This work contributes to an innovative modification method for natural and wearable protein fibers with antibacterial properties in a controllable and uniform way.