Cross wood was usually selected to fabricate oil-water separation function. However, the cross wood is easy to be deformed after chemical delignification. Therefore, structure optimization via drilling holes on radial wood along with nano Cu(OH)2/CuCl modification overcame the bottleneck defect of dimensional instability, and simultaneously fabricated oil-water separation function. The oil absorption capacity of modified wood increases with the number and depth of drilled holes, reaching a maximum of 3.7 g/g toward dichloromethane. The modified radial wood demonstrated exceptional filtration effectiveness toward dichloromethane/chloroform-water mixtures and exhibited superior photocatalytic degradation capabilities against methylene blue, malachite green, and direct blue 151 dyes. Additionally, the modified radial wood displayed favorable recycle ability for both oil- water separation and photocatalytic degradation. Thus, a facile, cost-effective and environmental friendly strategy proposed in this work has potential to enhance the practical application of wood based oil-water separation materials.

The urgent requirement of carbon reduction in the world provides wood products a historical opportunity to play a crucial role to fix carbon dioxide and reduce carbon emission. It is essential to reveal the in situ growth mechanism of copper nanoparticles on eucalyptus scrimber surface. Cu4(SO4)(OH)6 nanoflowers are in situ synthesized successfully on the surface of eucalyptus scrimber via a simple hydrothermal process in this work. The detailed nucleation and in situ growth process of Cu4(OH)6SO4 nanoparticles on the surface of eucalyptus scrimber, characterized by the trajectory of size evolution, are revealed first in this work. According to the classical nucleation theory, the nucleation stage of as prepared Cu4(SO4)(OH)6 nanoflowers includes nucleus formation and nucleus growth. Although the same initial precursor reactant is obtained at the nucleation stage, there are two types of early nanoparticles, with morphology of fusiform and strip shape being self assembled to nanoflower structure during the growth stage. Further, the modified eucalyptus scrimber exhibits excellent superhydrophobicity, UV durability, mold and moisture resistance, as well as reversible property. Therefore, the proposed in situ growth kinetics related to Cu4(OH)6SO4 nanoparticles on wood surface have potential to be a reference to develop multifunctional superhydrophobic wood-based material for variable applications. This study reveals the in situ growth mechanism of copper nanoparticles on the eucalyptus scrimber surface, including nucleation and evolution process. Further, the modified eucalyptus scrimber exhibits excellent superhydrophobicity, UV durability, mold resistance, and reversible property. image

Superhydrophobic surfaces have a number of potential applications including separating oil from water for pollution abatement. Wood is an excellent matrix for creating these surfaces because its interactive chemistry and intricate cellular matrix provides a large, reactive surface area for fabrication. The challenge to using wood is identifying simple pathways for in-situ synthesis. Na3(Cu2(CO3)3OH)center dot 4H2O was synthesized in-situ on deligni-fied balsa wood reacting copper chloride and sodium hydroxide in the presence of phenol formaldehyde (PF) resin, and then using stearic acid (STA) to modify this surface to be superhydrophobic. The modified wood surface was covered with Na3(Cu2(CO3)3OH)center dot 4H2O tetrahedral particles, and had a surface free energy of 8.0 J/ m2, which was about 90 % lower than that natural balsa wood. The modified wood had excellent absorption and filtration capabilities for various oils and was able to absorb 2.1-4.8 times its weight in oil, with oil absorption reaching a maximum of 5.2 g/g for chloroform. The modified wood could be regenerated and reused up to 14 times, and the still retained a separation efficiency of 90 % for a dichloromethane:water mixture within 11 cycles. The results suggest that wood-based superhydrophobic surfaces could represent a more environmentally benign material for remediating spills.

The less UV durability and weak chemical stability of superhydrophobic wood limited its wide application. Cu2(OH)3Cl nano particles, epoxy (EP), vinyltriethoxysilane (VTES), and room temperature vulcanized silicone rubber (RTV) were combined together to modify both soft and hard wood with function of superhydrophobic at once successfully. The modified wood was endowed not only superhydrophobicity as expected, such as CA more than 150 degrees, along with anti-fouling and self-cleaning properties, but also excellent durability, including well chemical, sandpaper abrasion, water impact and tape peeling stability. Most prominently, there was almost no color changing being observed on the modified samples. Furthermore, the best UV resistance, 3168 h consistently against UV irradiation, was achieved in the field of wood superhydrophobic modification. The proposed synergistic protective mechanism by synthesizing silicon dioxide and siloxane has potential to extend the service life and improve the high value utilization of wood product.

Blackberry inspired superhydrophobic poplar scrimber with superstrong ultra-violet (UV) resistance, self-healing and reversible functional superhydrophobicity was fabricated via in-situ growth of Cu7Cl4(OH)10 & BULL;H2O nano particles in the absence of low surface-free energy materials. Superhydrophobic poplar scrimber exhibited the best ultraviolet resistance over 1920 h of UV-irradiation at 340 nm, which could be the protection ascribed to UV light absorption by the hierarchical structure of Cu7Cl4(OH)10 & BULL;H2O. More importantly, superhydrophobicity was reversed by a simply drying process under humid conditions. The results provider a novel strategy for preparing a simple, multifunctional, and reversibly superhydrophobic wood-based engineering material.

Cuprous oxide (Cu2O) nanoparticles (NPs) was anchored on wood by simple spraying method, then both soft and hard wood has been endowed efficient function photocatalytic degradation toward organic dyes and formaldehyde gas synergistically. The best recycle ability of wood based photocatalyst toward organic pollutants was achieved, which was characterized by photocatalytic degradation efficiency of methylene blue (MB) more than 95% after 100 cycles, and formaldehyde gas over 85% after 60 cycles. Cu2O NPs@wood performed much lower forbidden bandwidth (Eg), which accelerated to generate much more radical of e- and finally promoted the capacity of photocatalytic degradation. The proposed Cu2O NPs@wood catalysts has potential to be applied both in the field of wastewater and air pollution remediation.

Sustainable wood-based materials with versatile functions such as ultraviolet resistance, superhydrophobicity, self-cleaning/antifouling capability, etc. have great potential to be used in building fields for replacing non-biodegradable fossil-based materials due to their facile preparation, biodegradability, and durability as well as the increasing concerns on environmental impact. Herein, pine-cone-shaped Cu7Cl4(OH)(10)center dot H2O nanoparticles were in situ synthesized by a hydrothermal process on a radial section of a poplar scrimber surface. As expected, the superhydrophobic function had been endowed to all three sections of the poplar scrimber surface, which exhibited excellent mechanical durability, desirable chemical stability, and splendid self-cleaning and antifouling capabilities. It should be noted that the modified poplar scrimber kept the superhydrophobic state even after 624 h of exposure to 340 nm ultraviolet (UV) irradiation, which could be ascribed to the unique hierarchical structure of the pine-cone-shaped Cu7Cl4(OH)(10)center dot H2O nanoparticles toward providing abundant voids for absorption of UV light. More importantly, a model of crystalline cellulose before and after compression was proposed to explain the improvement of physical and mechanical properties of poplar scrimber. This work will provide a new path for the superhydrophobic modification on wood-based engineering materials, which has potential to be applied in the industrial production of superhydrophobic wood scrimber to promote the sustainable development of timber resources.