Enhancing the durability of reversible wettability on larch wood surfaces through optimized pretreatment methods

Abstract

The development of superhydrophobic layers on wood is attracting plenty of scientific attention lately in the field of functional wood modification. However, the ability to resist mechanical wear is essential to improve the durability of the functional surface through simple treatment. Hot water, acid, and alkali were initially used to pre-treat larch wood samples, followed by a hydrothermal procedure to deposit zinc oxide (ZnO) nanostructures on the surface of the pretreated wood. Wood that has been pure water hydrothermally processed has a more distinctive ZnO structure with a compact arrangement and rod structure. After pretreatment, the surface contact angle of ZnO wood was greater than 150°, showing excellent superhydrophobic property, while the surface of directly loaded ZnO wood did not. Most importantly, in the test of wear resistance, hot water pretreated ZnO wood showed the optimized performance. The densely packed ZnO nanorods generated by hydrothermal pretreatment exhibit a more stable bond with the wood surface, thereby enhancing the mechanical stability of the wood to some extent both in the sandpaper wear and the tape tearing test. The superhydrophobic modified wood surface also had outstanding self-cleaning talents, which can also easily switch between light and heat caused a reversible shift in the surface wettability. This study offers insight into wood functionalization and addresses the endurance of surface changes on biomass materials.