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Novel in-situ freeze polymerization assisted layer-by-layer self-assembly method was used to prepare robust regenerated cellulose fiber-polypyrrole (RCF-PPy) composite fibers with high-conductivity, where transverse-longitudinal polypyrrole growth on RCF was regulated by using Lewis acid FeCl 3 in crystalline ice state with the template etching and oxidation effects. [Display omitted] • In-situ freeze polymerization assisted layer-by-layer assembly achieved high-conductivity composite fibers. • Modulate transverse-longitudinal PPy growth on RCF was regulated by FeCl 3 in crystalline ice state. • RCF-PPy3 formed continuous and stable conductive networks using low concentrations PPy. • RCF-PPy3 displayed high strength and exceptional durability. • RCF-PPy3 sensor was designed into various multifunctional intelligent textiles. Novel in-situ freeze polymerization assisted layer-by-layer self-assembly method was utilized to prepare robust regenerated cellulose fiber-polypyrrole (RCF-PPy) composite fibers with high-conductivity, where transverse-longitudinal polypyrrole growth on RCF was regulated by using Lewis acid FeCl 3 in crystalline ice state with the template etching and oxidation effects. The RCF-PPy3 exhibited high strength (1.01 cN/dtex) and exceptional durability, withstanding mechanical deformation, friction (100 cycles), and ultrasonic washing (50 times), addressing the issues of poor interface adhesion and conductivity stability of conductive fibers. Furthermore, the composite fiber demonstrated high electrical conductivity of 87.66 mS cm−1 and outstanding sensing performances for monitoring strain, pressure, temperature (0.34 %/°C), and humidity (0.895 %/RH). Based on RCF-PPy3, a pressure sensor was constructed as a human–machine interface electronic device, achieving sedentary reminders, fingertip information transmission, indicating great potential applications in intelligent wearable fiber electronic devices. [ABSTRACT FROM AUTHOR]

Our photocatalyst possesses homo/heterojunction structure, which consists of hexagonal CdS, cubic CdS and Prussian blue. This design of homo/heterojunction structure not only achieves ideal energy band structure, which makes for stable and rapid separation of photogenerated electrons-holes, but also improves stability of photocatalyst in various extreme circumstances. Therefore, the photocatalytic activity is significantly enhanced. [Display omitted] • The homo/heterojunctions structures were designed via one-pot kinetic regulation. • The rational energy band distribution enhances photocatalytic activity. • The strong chelation between cyanogroups and Cd2+ improve the stability. • The photocatalysts possess excellent reusability. Photoreduction of soluble U(VI) to insoluble U(IV) by CdS-based catalysts shows great potential in remediating radioactive wastewater in terms of environmental friendliness and desirable bandgap as well as the availability of CdS, but is still limited by undesirable efficiency and stability from photogenerated carrier recombination and photocorrosion. Herein, we have elegantly designed tailor-made CdS@Prussian blue with homo/heterojunctions via one-pot kinetic regulation. The key to such a structure is to leverage the outstanding binding affinity between cyanogroups of Prussian blue and Cd2+ to create diversity of local precursor concentration differences. With such unique structure and rational energy band distribution, our photocatalysts demonstrate an unprecedented U(VI) removal efficiency as high as 2.5 times that of the pristine CdS. More importantly, the strong chelation between cyanogroups and Cd2+ endows our catalysts with extremely excellent stability compared with other state-of-the-art composite photocatalysts. This work provides a facile and universal inspiration for homo/heterojunction engineering of high-performance photocatalysts for photoreduction of uranium. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) as catalysts for the activation of peroxymonosulfate (PMS) to remove recalcitrant organic contaminants has been well reported, however, the separation of MOFs from the solution is difficult because of their powder state, which limits their applications. In the present study, zeolitic imidazole framework (ZIF) materials, ZIF-9 and ZIF-12 were pioneered to load on cellulose aerogels, and the hybrid aerogels as metal catalysts to effectively activate PMS for Rhodamine B (RB), tetracycline hydrochloride (TC) and p-nitrophenol (PNP) degradation. The hybrid aerogels/PMS system could remove PNP about 90% in 1 h, which hard to remove from water. The pH value of the solution had no effect on the degradation process, which demonstrated that the hybrid aerogels had excellent pH tolerance. In addition, the mechanism of PNP degradation was investigated by electron paramagnetic resonance (EPR) and free radical trapping methods. The results showed that PMS could effectively activate by hybrid aerogels to produce sulfate radicals (SO 4 −), hydroxyl radicals ( OH), and revealed that SO 4 − play a key role in degradation. The most important feature of hybrid aerogels is can be easily separated from the solution. The obtained results showed that the hybrid aerogels exhibit excellent recyclability, with no significant effect on degradation. The prepared hybrid aerogels are green, environmentally friendly with high catalytic efficiency. Further, the outstanding degradation of PNP demonstrates the promising prospects of hybrid aerogels as advanced oxidation process (AOP) catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrophobic interactions and hydrogen bonded self-assembly achieve mild functionalization. • The membrane is with anti-fouling, anti-bacteria, and anti-adhesion properties. • The membranes could maintain 85% of adsorption capacity with various interferences. • The membranes could obtain 1.15 mg/g of uranium when the concentration is 3.3 ppb. Herein, we have developed a mild and convenient strategy to enable polypropylene (PP) fibrous membranes with abundant adsorption sites for the selective extraction of uranium from seawater. Lysozyme was chosen as the pre-coatings because of its strong hydrophobic interactions with PP membranes. Then, lysozyme and phytic acid were set as hydrogen bonding self-assembling components since both of them are proved with a great binding affinity towards uranium. The contents and thickness of the lysozyme-phytic acid coatings could be linearly tuned due to the excellent controllability of self-assembly. The obtained PP membrane could achieve adsorption capacity as high as 90.07 mg-U/g-membrane (2143.83 mg-U/g-coating). In addition, the lysozyme would endow the PP membranes with outstanding anti-fouling, anti-bacteria, and anti-adhesion properties. The modified membranes could maintain more than 85% of adsorption capacity even with the interferences of bacteria and model pollutants. We also applied the membranes for dynamic adsorption by taking advantage of membrane filtrations. The adsorption capacity during the dynamic process increases with the flow rates and the layer numbers because more uranyl ions could contact with the adsorption sites. The modified PP membranes could obtain 1.15 mg/g of uranium after 15 days when the concentration of uranium is set as the same as the uranium concentration (3.3 μg/L) in natural seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amyloid-like coatings provide electrodes with binding sites to uranium and anti-fouling properties. • The modified electrodes achieved equilibrium adsorption capacity as high as 2850 mg/g. • Unfolded BSA coatings enable the electrodes with superior reusability and long-term stability. • Both adsorption capacity and adsorption rates are better than most of other adsorbents. Electro-adsorption has been regarded as one of the most effective methods for uranium extraction from seawater since this method could gather ultralow-concentration uranyl ions at the adsorbent surfaces for higher adsorption capacity and adsorption rates. However, the marine microorganisms and pollutants would also migrate to the adsorbent surfaces, causing serious inhibiting effects. Herein, the pristine electrodes were modified by the convenient amyloid-like assembly to solve the above problem. The unfolded bovine serum albumin (BSA) coatings not only offer adsorption sites toward uranium but also enable the electrodes with excellent anti-fouling and anti-adhesion properties. The modified electrodes achieved superior reusability and long-term stability even with the interferences of various pollutants and microorganisms. To the best of our knowledge, the overlooked but pernicious influences of the fouling phenomenon are firstly investigated in electro-adsorption. This finding not only removes the barriers in the practical applications of electro-adsorption, but also guides the design strategy of adsorbents for uranium extraction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Durable and restored fireproof cotton fabrics were prepared via a facile strategy. • Prominent fire resistance and durability to 50 LCs with LOI of 32.7% was achieved. • The reduction in washing durability can be recovered by feasible acetic acid soaking. • Improved fire resistance was due to graphitized carbon layers and C/N heterocycles. Novel, durably flame-retardant cotton fabrics with fascinatingly restorable fire resistance were prepared by simple grafting of phosphate and melamine, which contributed to a phosphorous-nitrogen (P/N) synergism. During the preparation process, phosphate was grafted with the hydroxyl groups of cellulose to form P-O-C bonds; subsequently, melamine reacted with the aldehyde groups of cellulose generated from phosphorylation to form P/N modified fabrics (P/N-Cotton). The P/N synergistic effect endowed cotton fabric with prominent fire resistance and durability. The Limit oxygen index (LOI) was as high as 51.1 ± 0.3% and was maintained at 32.7 ± 0.8% after 50 laundering cycles (LCs). The total heat release (THR) and peak values of heat release rate (pHRR) of P/N-Cotton were significantly reduced by 70.11% and 64.19%, respectively. Amazingly, the modified cotton fabrics exhibited restorable fire resistance once immersed into the acetic acid solution due to the ion exchange between Na+ from detergent and H+ from acetic acid. The LOI of P-Cotton and P/N-Cotton after 50 LCs can be restored to 32.4 ± 0.7% and 35.7 ± 0.7% from 20.8 ± 0.7% and 32.7 ± 0.8%, respectively. The analysis of gas-phase products and residual char demonstrated that the incorporation of phosphate and melamine facilitated cellulose fibers to convert to dense and stable graphitized carbon layers and carbon-nitrogen heterocycles, effectively protecting the fabric from decomposing to flammable gases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cellulose-based absorbents with the highest reported uranium uptake are achieved. • Homogeneous reactions are beneficial to grafting density and material utilization. • Excellent hydrophilicity contributes to rapid mass transfer and antifouling property. • The adsorbents could be filled into filtration columns for dynamic adsorption. • The adsorbents collect 50 mg uranium/g from simulated seawater in 24 d adsorption. Highly efficient extraction of uranium from seawater is regarded as an important guarantee for the promotion of nuclear electricity generation. Amidoxime based adsorbents are considered as the most promising materials for uranium recovery due to their high selectivity and binding capability to uranyl ions. Herein, natural celluloses with advantages of low cost, biodegradability, renewability were chosen as the raw materials. Moreover, amidoximated cellulose-based adsorbents are fabricated by two steps of homogeneous reactions including the Michael addition and amidoximation reaction. Compared with traditional surface grafting methods, both the grafting density of active adsorption sites and the utilization of raw materials could be greatly improved because of the lower steric hindrance as well as more exposed reactive sites during the homogeneous reactions. The adsorption capacity of our adsorbents can reach as high as 517.07 mg/g at pH = 7, one of the best cellulose-based adsorbents as far as we know. In addition, excellent hydrophilicity of the adsorbents, which is inherited from the natural cellulose, can endow them with enhanced mass transfer as well as resistance to marine pollutants. More importantly, the adsorption microspheres would be filled into filtration column for dynamic adsorption benefited from their aforementioned merits. The average adsorption capacity could maintain above 2.5 mg/g per day when the filtration column was exposed to simulated seawater for 24 days. All these characteristics make the amidoximated cellulose-based adsorbents potentially applicable to the uranium recovery from seawater. [ABSTRACT FROM AUTHOR]

• Biosynthesis of Au NPs was facially achieved using an alkali chitosan solution. • Dissolved chitosan with anchored Au NPs were self-assembled into a 3D architecture. • Well dispersed Au NPs with nanogaps led to excellent SERS EF and reproducibility. • Shapable, porous and pH-sensitive feature promoted good molecular selectivity. As a cost-efficient method for detecting analyses at trace level, chitosan-based surface-enhanced Raman scattering (SERS) sensor is a promising alternative. However, research on this technique is frequently hindered to complicated operations, dissatisfactory sensing and reproducible property. Herein, a biosynthesis of Au nanoparticles (NPs) was facially achieved through adding AuCl 4 ions into a dissolved alkali chitosan dope without using any heating operation or extra reductant. Subsequently, through hydrogen bonds-driven self-assembly during the coagulation process, chitosan nanofibrils anchored with Au NPs grew into a three-dimensional (3D) architecture. Because of the well-dispersed Au NPs with a content of 0.91–2.78 wt% and emerged sub-10 nm nanogaps, the prepared Au-embedded chitosan (Au@CS) nanocomposite could serve as excellent SERS substrate. The enhancement factor approached 107 and spot-to-spot reproducibility could be as low as 5.66% for detecting 4-mercaptobenzoic acid (4-MBA). Besides, owing to the innate pH-sensitive characteristic, the SERS substrate demonstrated molecular-selective detection of charge dye molecules. Furthermore, thanks to its hierarchical porosity and mechanical flexibility, straightforward trace detections of melamine in milk and pesticides on the fruit surface were realized using this SERS substrate. This simple and highly efficient SERS substrate provides great opportunity in the field of environmental management and food safety. [ABSTRACT FROM AUTHOR]

• Phase change nanofibers (PCF) demonstrated solid–solid phase change performance. • Obtaining PCF composite with excellent shape-stability and energy storage efficiency. • PCF composite shows "on–off" drug release in response to phase change temperature. • PCF composite with 5 wt% f- CNC-ZnO displayed a sustained release of more than 78.9% within 336 h. Thermo/light-responsive functionalized cellulose nanocrystal-zinc oxide (f- CNC-ZnO) nanohybrids based poly (3-hydroxybutyrate-co-3-hydroxy valerate) (PHBV) phase change nanofiber (PCF) composites with highly thermal energy storage ability were developed for controllable drug release applications. Under sunlight irradiation, the PCF composite (without f- CNC-ZnO) absorbed light and stored the thermal energy with 46.3% efficiency. An "on–off" temperature regulation of tetracycline hydrochloride (TH) release was found for PCF composites according to phase change temperature. At the temperature close to the melting point of PEG at 60 °C, the PCF composite with 5 wt% f- CNC-ZnO displayed a sustained release of more than 40.5 and 78.9% of tetracycline hydrochloride (TH) were released over two weeks for the 10 and 30 wt% drug loading. Thus, the PCF composites with excellent thermo/light-responsive properties and high energy storage efficiency are beneficial for promising sustainable thermal storage and drug delivery systems. [ABSTRACT FROM AUTHOR]