The main challenges of a solar steam generation device based on biomass materials are complicated processing techniques and relatively low efficiency. To solve these problems, we reported a simple immersion treatment method by depositing polydopamine (PDA) and silver nanoparticles (AgNPs) on natural wood to prepare a novel solar interface evaporation device. Ag-PDA@wood exhibits a unique bilayer structure. The absorbance of the top light absorption layer is higher than 96% in a wide wavelength range (300-2500 nm). Owing to the synergistic photothermal effect between PDA and AgNPs, Ag-PDA@wood has ultrafast solar-thermal response (a temperature increase of 42.5 °C within 5 min under 1 sun), and more heat is located at the steam generation interface (the surface temperature is 45.1 °C). The natural wood layer at the bottom with low thermal conductivity provides sufficient water supply and reduces the bulk heat loss. A high evaporation rate of 1.58 kg m-2 h-1 is achieved using Ag-PDA@wood under 1 sun (1 kW m-2). Its evaporation efficiency reaches 88.6%. The results upon sewage treatment and seawater desalination indicate that Ag-PDA@wood has an excellent purification ability and self-desalting capacity. More importantly, when compared to traditional solar evaporators, Ag-PDA@wood exhibits high antibacterial activity. The result of this antibacterial experiment shows that this material almost completely kills harmful bacteria. Therefore, Ag-PDA@wood has a high application potential in seawater desalination and sewage purification, providing a significant incentive to solve the problem of insufficient freshwater supply.

Wood-Based Solar Interface Evaporation Device with Self-Desalting and High Antibacterial Activity for Efficient Solar Steam Generation.

Statistical Design And Analysis Of Experiments With Applications To Engineering And Science

Rational Design of High-Performance Bilayer Solar Evaporator by Using Waste Polyester-Derived Porous Carbon-Coated Wood

Solar steam generation as a promising solar energy conversion technology has attracted considerable interest in achieving seawater desalination and water purification. Although wood with fast water transportation and excellent heat localization has drawn particular interest in regard to its application for solar steam generation, challenges still remain in terms of its complicated processing techniques and relatively low efficiency. Here, we propose a facile, cost-efficient, and scalable brushing method to prepare an aluminophosphate-treated wood (Wood@AlP) solar steam generation device. The aluminophosphate compound deposited on the wood surface can not only be considered as the Lewis acid catalyst capable of accelerating the formation of the carbon layer but also provide an aluminophosphate layer with a hierarchical porous structure, which is beneficial for broad solar absorption and vapor escape. On the other hand, benefiting from the natural hydrophilicity, low thermal conductivity, and excellent water transportation of wood, the obtained Wood@AlP device can float on seawater and exhibit a high solar thermal efficiency of 90.8% with a net evaporation rate of 1.423 kg m-2 h-1 under 1 sun illumination.

Hierarchical Porous Aluminophosphate-Treated Wood for High-Efficiency Solar Steam Generation.

A facile method inspired by the cake making process is developed to fabricate reduced graphene oxide wrapped plant fiber sponges (PFS@rGO) through in situ coating and foaming. This method avoids the use of energy-intensive equipment for molding and drying, and hence has great potential in the production of large-sized rGO sponges. With a highly porous framework, good mechanical properties, efficient solar absorption, and low thermal conductivity, the as-fabricated hydrophilic and light-weight PFS@rGO readily floats on seawater and generates water vapor with a solar thermal conversion efficiency of 88.8% under 1 sun illumination.

A cake making strategy to prepare reduced graphene oxide wrapped plant fiber sponges for high-efficiency solar steam generation

Mesoporous aluminosilicate improves mildew resistance of bamboo scrimber with CuBP anti-mildew agents

To improve mechanical properties of ultra-low density fiberboards (ULDFs), Si-Al compounds were mixed together with fibers during preparation of ULDFs, forming a thin film on the surface of the fibers via hydrogen bonding. This work mainly optimized two proposed methods in which the inorganic thin film was assembled on the surface of fibers, in terms of its effect on the mechanical properties of fibers. Microstructural characterization (such as micromorphology and elemental distribution, chemical bonding, and crystalline phase) of Si-Al compounds and ULDFs was done to evaluate the effects. The results revealed that an inorganic thin film (probably Al2O3-SiO2) covered the surface of the fibers. Compared with the control specimen, the modulus of elasticity, modulus of rupture, and internal bond strength of the specimen treated by the sol-gel process increased from 3.87 MPa to 13.19 MPa, 0.05 MPa to 0.16 MPa, and 0.010 MPa to 0.025 MPa, respectively. Based on its higher mechanical properties, a combined sol-gel method was judged to be better for enhancement of fibers than a separate deposition method.

Modification of Ultra-Low Density Fiberboards by an Inorganic Film Formed by Si-Al Deposition and their Mechanical Properties

An ultra-low density fiberboard was made of plant fiber using a liquid frothing approach. The inflammability of the plant fiber limited its application as a candidate for building insulation materials and packaging buffering materials. Si-Al compounds were introduced into the foaming system because of the high temperature resistance of Si and Al compounds. The results from energy-dispersive spectroscopy suggested that the Si and Al relatively evenly covered the surface of the fibers, and their weight ratios in the material increased as a function of the amount of Si-Al compounds. The increasing weight ratios of Si and Al affected the fire properties of the material, reducing the released amount of heat, smoke, and off-gases such as CO and CO2, as well as decreasing the mass loss percentage, shown through the use of a Cone Calorimeter. It follows that Si-Al compounds have an evident collaborative effect on the halogen fire retardant. The system can effectively restrain the fire hazard intensity and the yields of solid and gas volatiles.

https://ojs.cnr.ncsu.edu/index.php/BioRes/article/download/BioRes_09_2_2415_Niu_Fire_Properties_Fiberboard/2660

Effect of Si-Al compounds on fire properties of ultra-low density fiberboard

This study investigates the application of mesoporous aluminosilicate material with hierarchical porosity to ultralow density wood fiber composite (ULD_WFC) for improving their mechanical properties. A 300 nm thickness Si–Al inorganic film was applied to the surface of the fibers. The mesoporous aluminosilicate material with many mesopores ranging from 2 to 20 nm was obtained. Their total pore volume and Brunauer–Emmett–Teller surface area were 0.193 cm3/g and 355.2 m2/g, respectively. Thermogravimetric analysis indicated that the thermostability of ULD_WFCs was affected by Si–Al compounds. But the residual weight of ULD_WFC with Si–Al compounds was 23.87% greater than composite without Si–Al compounds. The X-ray diffraction analysis indicated partial conversion of SiO2 to α-SiC. These conditions attributed to improving the mechanical properties of ULD_WFC. The modulus of elasticity, modulus of rupture, and internal bond strength of composite with Si–Al compounds increased by 547.4%, 240.0%, and 400.0%, r...

Min Niu

Papers

Hierarchical Porous Aluminophosphate-Treated Wood for High-Efficiency Solar Steam Generation.

Mesoporous aluminosilicate improves mildew resistance of bamboo scrimber with CuBP anti-mildew agents

Modification of Ultra-Low Density Fiberboards by an Inorganic Film Formed by Si-Al Deposition and their Mechanical Properties

Effect of Si-Al compounds on fire properties of ultra-low density fiberboard

Mesoporous Aluminosilicate Material with Hierarchical Porosity for Ultralow Density Wood Fiber Composite (ULD_WFC)