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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.

A facile method for fabricating the superhydrophobic bamboo timber based on an anatase TiO 2 film for acid rain protection and flame retardancy is described in the present work. The bamboo timber with the maximal water contact angle of 154° has been prepared by the hydrothermal deposition of anatase TiO 2 nanoparticles and further modified with octadecyltrichlorosilane (OTS). The geometric microstructure of anatase TiO 2 nanoparticles and chemical composition of the superhydrophobic coating were analyzed by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The wetting behavior of bamboo timber samples was investigated by water contact angle (WCA) measurement.The results indicated that the strong hydrogen bonds were formed between the amorphous TiO 2 and the hydroxide radicals of bamboo timber surface, and the strong interaction contributed to the heat stability enhancement of the TiO 2 /bamboo timber composites. Moreover, diverse performances of superhydrophobic bamboo timber have been evaluated as well. The treated bamboo timber exhibited the 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.

The surfaces of plants represent multifunctional interfaces between the organisms and the environment. In this paper, biomimetic taro leaf-like structures with superparamagnetic and superhydrophobic performances were exactly copied on the wood surface through the soft lithography to improve the wood properties. Fe 3 O 4 nanoparticles were mixed into poly(dimethylsiloxane) PDMS suspensions to obtain Fe 3 O 4 /PDMS suspensions that commonly endow coats magnetic and microwave absorption properties, which were then cast onto the wood surface and packaged by PDMS stamps replicated from fresh taro leaves. Fe 3 O 4 /PDMS films, which coexisted superhydrophobic surface and superparamagnetic property, were created on the wood surface after the being dried and stamps were peeled off. The as-prepared wood surface exhibited unique taro leaf-like micro-and nanostructures, microwave absorption, superparamagnetism performances with maximum saturation magnetization (M s ) of 22.9 emu g -1 and superior static superhydrophobicity with a water contact angle of 152°± 2°. This research may provide a feasible pathway for constructing naturally biomorphic structures on the wood surface with tailored functions.

Liquid ammonia is considered a sustainable liquid fuel and an easily transportable carrier of hydrogen energy; however, its synthesis processes are energy-consuming, high cost, and low yield rate. Herein, we report the electrocatalytic reduction of nitrate (NO3 –) (ERN) to ammonia (NH3) with nickel phosphide (Ni2P) used as a noble metal-free cathode. Ni2P with (111) facet was grown in situ on nickel foam (NFP), which was regarded as a self-supporting cathode for ERN to synthesis NH3 with high yield rate (0.056 mmol h–1 mg–1) and superior faradaic efficiency of 99.23%. The derived atomic H (*H), verified by a quenching experiment and an electron spin resonance (ESR) technique, effectively enhanced the high selectivity for NH3 generation. DFT calculations indicated that *NO3 was deoxygenated to *NO2 and *NO, and *NO was subsequently hydrogenated with *H to generate NH3 with an energy releasing process (ΔG < 0). OLEMS also proved that NO was the merely gas intermediate. NFP exhibited the unique superhydrophilic surface, metallic properties, low impedance, and abundant surface sites, favorable for adsorption of NO3 –, generation of *H, and then hydrogenation of NO3 –. Hence, NFP cathode showed high selectivity for NH3 (89.1%) in ERN. NFP with long-term stability and low energy consumption provides a facile strategy for synthesis of NH3 and elimination of NO3 – contamination.

Bradyrhizobium japonicum (BJ), which has a symbiotic relationship with soybean roots, possessed an abundant three-dimensional (3D) structure with a high N content. A soybean leaf (SL) with a hierarchically ordered macroporous network and numerous polar hydroxyl groups was proposed as a separator for a supercapacitor. A 3D hierarchical porous carbon was prepared by the facile carbonization with chemical activation of BJ. The as-prepared material possesses a large specific surface area (1275 m2·g–1), unique 3D hierarchical porosity, and good electrical conductivity. The electrochemical performance of the Bradyrhizobium japonicum-derived porous carbons at a mass ratio of 1.5 (ZnCl2/BJ = 1.5) (BJPC-1.5) for supercapacitors with a SL separator showed a high capacitance (358 F/g at 1 A·g–1), a superior cycle stability of 91% over 8000 cycles, and a superior rate capability in a symmetric two-electrode supercapacitor in 6 M KOH. Furthermore, the electrochemical performance of the BJPC-1.5 with a SL separator was comparable to that with the commercialized cellulose and polypropylene (PP) separators. More attractively, the SL separator with a preferable water uptake showed a much better performance in the BJPC-1.5 cell than the PP separator. These results provide an insight into the full usage of a natural and biodegradable biomass for separator and electrode materials for a supercapacitor.

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.

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.