Bitao Fan

Fabrication of superhydrophobic bamboo timber based on an anatase TiO2 film for acid rain protection and flame retardancy

A facile method for fabricating superhydrophobic bamboo timber based on an anatase TiO2 film for acid rain protection and flame retardancy is described in the present work. Bamboo timber with a maximal water contact angle of 154° has been prepared by the hydrothermal deposition of anatase TiO2 nanoparticles and further modified with octadecyltrichlorosilane (OTS). The geometric microstructure of the anatase TiO2 nanoparticles and the chemical composition of the superhydrophobic coating were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The wetting behavior of the bamboo timber samples was investigated by water contact angle (WCA) measurements. The results indicated that strong hydrogen bonds were formed between the amorphous TiO2 and the hydroxide radicals of the bamboo timber surfaces, and the strong interaction contributed to the heat stability enhancement of the TiO2/bamboo timber composites. Moreover, the diverse performance of the superhydrophobic bamboo timber has been evaluated as well. The treated bamboo timber exhibited outstanding superhydrophobicity, excellent waterproofing durability, acid rain resistance, and flame retardancy, offering a potential opportunity to accelerate the large-scale production of superhydrophobic woody material for new industrial applications.

A simple, one-step hydrothermal approach to durable and robust superparamagnetic, superhydrophobic and electromagnetic wave-absorbing wood.

In this work, lamellar MnFe2O4 was successfully planted on a wood surface through the association of hydrogen bonds via the one-pot hydrothermal method. Simultaneously, the fluoroalkylsilane (FAS-17) on the surface of the MnFe2O4 layer formed long-chain or network macromolecules through a poly-condensation process and provided a lower surface energy on the wood surface. The MnFe2O4/wood composite (FMW) presented superior superparamagnetism, superhydrophobicity and electromagnetic wave absorption performance. The results indicated a saturation magnetization of the FMW with excellent superparamagnetism of 28.24 emu·g−1. The minimum value of reflection loss of the FMW reached −8.29 dB at 16.39 GHz with a thickness of 3 mm. Even after mechanical impact and exposure to corrosive liquids, the FMW still maintained a superior superhydrophobicity performance.

Cellulose as an adhesion agent for the synthesis of lignin aerogel with strong mechanical performance, Sound-absorption and thermal Insulation

The lignin aerogels that are both high porosity and compressibility would have promising implications for bioengineering field to sound-adsorption and damping materials; however, creating this aerogel had a challenge to adhesive lignin. Here we reported cellulose as green adhesion agent to synthesize the aerogels with strong mechanical performance. Our approach—straightforwardly dissolved in ionic liquids and simply regenerated in the deionized water—causes assembly of micro-and nanoscale and even molecule level of cellulose and lignin. The resulting lignin aerogels exhibit Young’s modulus up to 25.1 MPa, high-efficiency sound-adsorption and excellent thermal insulativity. The successful synthesis of this aerogels developed a path for lignin to an advanced utilization.

A 3D titanate aerogel with cellulose as the adsorption-aggregator for highly efficient water purification

Making full use of the hydrophilicity, hydroxyl reactivity, high strength and stiffness, low weight and biodegradability of cellulose, a novel cellulose-based adsorption-aggregator is creatively exploited. In this work, a 3D titanate aerogel with cellulose as the adsorption-aggregator has been fabricated for highly efficient water purification. Herein, the polyhydric cellulose not only acts as a crosslinking agent, but also facilitates ion-induced aggregation, which strongly promotes the adsorption efficiency of the titanate and effectively improves its inherent shortcomings as an inorganic adsorbent. The Pb2+, Sr2+, Cu2+, Ra2+, and Cd2+ adsorption capacities surprisingly reach 2.46, 1.43, 2.51, 1.22, and 1.98 mmol g−1, respectively. Moreover, it may be applied in the fields of water purification agents, oxidants, catalysts, disinfectants and photoelectrochemical components, in view of the hydroxyl oxidation, hydroxyl induction, disinfection, and water purification abilities of cellulose. Therefore, the development of cellulose adsorption-aggregating agents is both reasonable and of great value.

One-step solvothermal deposition of ZnO nanorod arrays on a wood surface for robust superamphiphobic performance and superior ultraviolet resistance

In the present paper, uniformly large-scale wurtzite-structured ZnO nanorod arrays (ZNAs) were deposited onto a wood surface through a one-step solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential thermal analysis (DTA). ZNAs with a diameter of approximately 85 nm and a length of approximately 1.5 μm were chemically bonded onto the wood surface through hydrogen bonds. The superamphiphobic performance and ultraviolet resistance were measured and evaluated by water or oil contact angles (WCA or OCA) and roll-off angles, sand abrasion tests and an artificially accelerated ageing test. The results show that the ZNA-treated wood demonstrates a robust superamphiphobic performance under mechanical impact, corrosive liquids, intermittent and transpositional temperatures, and water spray. Additionally, the as-prepared wood sample shows superior ultraviolet resistance.

3D assembly based on 2D structure of Cellulose Nanofibril/Graphene Oxide Hybrid Aerogel for Adsorptive Removal of Antibiotics in Water

Cellulose nanofibril/graphene oxide hybrid (CNF/GO) aerogel was fabricated via a one-step ultrasonication method for adsorptive removal of 21 kinds of antibiotics in water. The as-prepared CNF/GO aerogel possesses interconnected 3D network microstructure, in which GO nanosheets with 2D structure were intimately grown along CNF through hydrogen bonds. The aerogel exhibited superior adsorption capacity toward the antibiotics. The removal percentages (R%) of the antibiotics were more than 69% and the sequence of six categories antibiotics according to the adsorption efficiency was as follows: Tetracyclines > Quinolones > Sulfonamides > Chloramphenicols > β-Lactams > Macrolides. The adsorption mechanism was proposed to be electrostatic attraction, p-π interaction, π-π interaction and hydrogen bonds. In detail, the adsorption capacities of CNF/GO aerogel were 418.7 mg·g−1 for chloramphenicol, 291.8 mg·g−1 for macrolides, 128.3 mg·g−1 for quinolones, 230.7 mg·g−1 for β-Lactams, 227.3 mg·g−1 for sulfonamides, and 454.6 mg·g−1 for tetracyclines calculated by the Langmuir isotherm models. Furthermore, the regenerated aerogels still could be repeatedly used after ten cycles without obvious degradation of adsorption performance.

Fabrication of Cellulose Nanofiber/AlOOH Aerogel for Flame Retardant and Thermal Insulation

Cellulose nanofiber/AlOOH aerogel for flame retardant and thermal insulation was successfully prepared through a hydrothermal method. Their flame retardant and thermal insulation properties were investigated. The morphology image of the cellulose nanofiber/AlOOH exhibited spherical AlOOH with an average diameter of 0.5 μm that was wrapped by cellulose nanofiber or adhered to them. Cellulose nanofiber/AlOOH composite aerogels exhibited excellent flame retardant and thermal insulation properties through the flammability test, which indicated that the as-prepared composite aerogels would have a promising future in the application of some important areas such as protection of lightweight construction materials.

Stress sensitive electricity based on Ag/cellulose nanofiber aerogel for self-reporting

A self-reporting aerogel toward stress sensitive slectricity (SSE) was presented using an interconnected 3D fibrous network of Ag nanoparticles/cellulose nanofiber aerogel (Ag/CNF), which was prepared via combined routes of silver mirror reaction and ultrasonication. Sphere-like Ag nanoparticles (AgNPs) with mean diameter of 74nm were tightly anchored in the cellulose nanofiber through by the coherent interfaces as the conductive materials. The as-prepared Ag/CNF as a self-reporting material for SSE not only possessed quick response and sensitivity, but also be easily recovered after 100th compressive cycles without plastic deformation or degradation in compressive strength. Consequently, Ag/CNF could play a viable role in self-reporting materials as a quick electric-stress responsive sensor.

Hydrothermal Synthesis of Nanooctahedra MnFe2O4 onto the Wood Surface with Soft Magnetism, Fire Resistance and Electromagnetic Wave Absorption

In this study, nanooctahedra MnFe2O4 were successfully deposited on a wood surface via a low hydrothermal treatment by hydrogen bonding interactions. As-prepared MnFe2O4/wood composite (MW) had superior performance of soft magnetism, fire resistance and electromagnetic wave absorption. Among them, small hysteresis loops and low coercivity (<±5 Oe) were observed in the magnetization-field curve of MW with saturation magnetization of 28.24 emu/g, indicating its excellent soft magnetism. The MW also exhibited a good fire-resistant property due to its initial burning time at 20 s; while only 6 s for the untreated wood (UW) in combustion experiments. Additionally, this composite revealed good electromagnetic wave absorption with a minimum reflection loss of −9.3 dB at 16.48 GHz. Therefore, the MW has great potential in the fields of special decoration and indoor electromagnetic wave absorbers.

New Insight on Promoted thermostability of poplar wood modified by MnFe 2 O 4 nanoparticles through the pyrolysis behaviors and kinetic study

In this study, we employed pyrolysis behavior and kinetics by Flynn–Wall–Ozawa method and Friedman method to analysis the thermostability of the MnFe2O4 nanoparticles/poplar wood composite, and analyzed the change of different proportion of MnFe2O4 in these composites for the thermostability by contrasting activation energy between the different samples. The pyrolysis processes of these composites were comprehensively investigated at different heating rates (10, 20, 30 and 40 °C/min−1) and pyrolysis temperatures of 600 °C in N2 and air atmosphere. These results indicated the thermostability of composites improved as the proportion of the MnFe2O4 nanoparticles increased. And the structure analyses of these composites from the microscopic view point of nanoparticles were applied to analysis the reason of thermostability enhancement of the poplar wood after coating MnFe2O4 nanoparticles. Additionally, due to its high initial oxidative decomposition temperature under air atmosphere, this composite and its preparation method might have high application potential, such as flameresistant material and wood security storage. This method also could provide a reference for other biomass materials. Synthesized MnFe2O4/C composite under the guidance of pyrolysis behaviors and kinetic study in N2 atmosphere exhibited good adsorption capacity (84.18 mg/g) for removing methylene blue dye in aqueous solution and easy separation characteristic.