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The simultaneous removal and selective separation of U(VI) and Th(IV) via adsorption remain challenging due to their strong mobility, reactivity, and similar chemical properties. Thus, a surface-functioned lignin nanoparticle (AL-PEI) was synthesized to adsorb U(VI)/Th(IV) in a unitary system via a pH-dependent process. In alkaline solution, AL-PEI exhibited excellent adsorption performance, and the maximum adsorption capacities for U(VI) and Th(IV) reached 392 and 396 mg/g, respectively. Discrepantly in acidic solution, the adsorption performance of AL-PEI for U(VI) could still reach a high capacity (332 mg/g), whereas highly limited adsorption capacity (less than 40 mg/g) for Th(IV) was obtained, and the separation factor of U(VI) from U(VI)-Th(IV) matrix significantly reached 6662 in 3 M of the HNO 3 medium. The simultaneously efficient adsorption in alkaline solution and highly selective separation performance in acidic solution of AL-PEI also showed excellent anti-ions interference capacities, high reusability, and strong stability. This study is the first to apply lignin fabricating radiation-resistant adsorbent material, and the adsorbent displays good performance for U(VI)/Th(IV) removal and selective separation via a novel pH-dependent process, which is important to the green and sustainable development of nuclear energy and environmental protection., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Trace anionic dyes in wastewater are difficult to be rapidly and efficiently removed because they are completely soluble and poorly biodegradable. Herein, a facile and environmentally friendly adsorbent was fabricated via the surface functioned SiO 2 with abundant amine groups of polyethyleneimine (PEI). The structural characterization indicated that PEI was successfully immobilized on the SiO 2 surface. The adsorption performance of SiO 2 -PEI was evaluated using acid orange II (AOII) as model pollutant. The adsorption of AOII on SiO 2 -PEI displayed high removal rates in the pH range of 2.0-9.0, and exhibited ultrafast removal (99.1% removal rate at 10 min). The adsorption behavior fitted well with the Langmuir isotherm and pseudo-second-order kinetic model, and the maximum uptake capability of AOII was higher than 705.3 mg/g. The excellent adsorption capacity of AOII on SiO 2 -PEI mainly relied on the electrostatic attraction between the sulfonic acid group of AOII and amine group of PEI in the adsorption process. Additionally, other anionic dyes like acid fuchsin and direct sky blue 5B could also be fast and efficiently removed by SiO 2 -PEI. This work is expected to open new possibilities for the ultrafast removal of anionic dye pollutants., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Gamma rays is widely used in modern science and technology, but it may cause health damage to practitioners. In the present study, natural composites based on leather and high-Z elements (atomic number ≥ 56) were fabricated and used as gamma rays shielding materials. These shielding materials were prepared by coating rare earth nanoparticles (Er2O3 or La2O3) onto the surface of natural leather, which was first impregnated with Bi3+ and Ba2+. Results show that the attenuation efficiency of the prepared Er1.31Bi5.46-NL (1.31 and 5.46 mmol cm−3 loaded elements) with thickness of 3.2 mm was 61.57% for incident rays at 121.78 keV (152Eu) and reached 96.4% in the incident of 59.5 keV (241Am), which is comparable to that of 0.25-mm lead plate (54.54 mmol cm−3). In addition, these natural-leather-based shielding materials exhibited low density (approximately 1/10 of Pb), high strength and wearable behaviors. [ABSTRACT FROM AUTHOR]

Bayberry tannin (BT), a natural plant polyphenol, is used for the one-step synthesis of Au@Pd core–shell nanoparticles (Au@Pd NPs) in aqueous solution at room temperature. Due to its mild and stepwise reduction ability, BT was able to preferentially reduce Au3+ to Au NPs when placed in contact with an Au3+/Pd2+ mixture, and subsequently, the formed Au NPs served as in situ seeds for the growth of a Pd shell, resulting in the formation of Au@Pd NPs. Importantly, it is feasible to adjust the morphology of the Pd shell by varying the Pd2+/Au3+ molar ratio. Au@Pd NPs with a spherical Pd shell were formed when the Pd2+/Au3+ molar ratio was 1/50, while Au@Pd NPs with cubic Pd shell predominated when the ratio was increased to 2/1. The core–shell structure of synthesized Au@Pd NPs was characterized by TEM, HAADF-STEM, EDS mapping, an EDS line scan, and EDS point scan. Furthermore, density functional theory (DFT) calculations suggested that the localization of BT molecules on the surface of the Au clusters was the crucial factor for the formation of Au@Pd NPs, since the BT molecules increased the surface negative charges of the Au NPs, favoring the attraction of Pd2+ over Au NPs and resulting in the formation of a Pd shell. [ABSTRACT FROM AUTHOR]

A facile method for one-step synthesis of size-controlled gold nanoparticles (AuNPs) supported on collagen fiber (CF) at room temperature was proposed. Epigallocatechin-3-gallate (EGCG), a typical plant polyphenol, was grafted onto CF surface to serve as reducing/stabilizing agent, so that the AuNPs were generated on CF surface without introduction of extra chemical reagents or physical treatments. The prepared AuNPs were fully characterized, and the results showed that the dispersed AuNPs were successfully produced and the mean particle size of AuNPs could be effectively controlled in range of 18 to 5 nm simply by varying the grafting degree of EGCG on CF surface. These stabilized AuNPs were found to be active heterogeneous catalysts for the reduction of 4-nitrophenol to 4-aminophenol in aqueous phase. The catalytic behaviors of AuNPs depended on the particle size and the grafting degree of EGCG. A distinct advantage of these catalysts is that they can be easily recovered and reused at least twenty times, because of the high stability of the AuNPs supported by EGCG-grafted CF. [ABSTRACT FROM AUTHOR]

The article focuses on a study which investigated the effect of nanoparticles on the mechanical properties, morphology, thermal sensitivity and water vapor permeability (WVP) of thermal-sensitive polyurethane (TSPU)/titanium dioxide nanohybrid membranes. The study found that the titanium dioxide content influenced the WVP of the nanohybrid membranes. Scanning electron microscopy (SEM) revealed that the titanium dioxide nanoparticles are evenly distributed in TSPU.

Homogeneous BT-stabilized Pd(0) nanoparticles are highly active for the biphasic hydrogenation of hydrophobic substrates because BT is an amphiphilic polymer that can form hydrophobic bonds with the organic phase, thus increasing the possibility of catalytic species to contact with hydrophobic substrates. [ABSTRACT FROM AUTHOR]

Colorectal cancer is currently the second most prevalent form of cancer in most developed nations and increasing incidence in developing nations. In article number 1800241, Junling Guo, Xuepin Liao, and co‐workers apply natural polyphenols from green tea and rare earth metal ions to construct supramolecular metal‐phenolic network nanoparticles. These nanoparticles exhibit an antitumor effect against colon cancer through the induction of apoptosis via a mitochondria‐associated pathway. [ABSTRACT FROM AUTHOR]

Engineering functional nanomaterials to have both high therapeutic efficacy and minimal side‐effects has become a promising strategy for next‐generation cancer treatments. Herein, an adenosine triphosphate (ATP) depletion and reactive oxygen species‐enhanced combination chemotherapy platform is introduced whereby therapeutic samarium (Sm3+) ions and (−)‐epicatechin (EC) are integrated via a metal‐phenolic network (SmIII‐EC). The independent pathway between Sm3+ and EC can achieve a synergistic therapeutic effect through the mitochondrial dysfunction process. SmIII‐EC nanoparticles cause a significant reduction of viability of C26 murine colon carcinoma cells while with lower systemic toxic effects on normal cell lines. SmIII‐EC nanoparticles are used to directly compare with a clinic anticancer drug 5‐fluorouracil. SmIII‐EC nanoparticles not only decrease the tumor volume but also do not affect the body weight of mice and normal organs, showing significant advantages over clinic counterpart. These facts suggest that SmIII‐EC nanoparticles represent a clinically promising candidate for colon cancer treatment with a targeted therapeutic effect and minimum side toxicity. Therapeutic Sm3+ ions and (−)‐epicatechin are integrated via a biocompatible metal‐phenolic network to provide ATP depletion and reactive oxygen species‐enhanced combination cancer chemotherapy. [ABSTRACT FROM AUTHOR]

Abstract: A series of Rh nanoparticles were prepared by using plant tannins as stabilizers. The as-prepared plant tannin-stabilized Rh nanoparticles were subsequently characterized by TEM, DES, FTIR and XPS. Due to the amphiphilic nature of plant tannins, the plant tannin-stabilized Rh nanoparticles were highly active in aqueous–organic biphasic hydrogenation of styrene. Furthermore, the as-prepared Rh catalyst can be reused 5 times without significant loss of catalytic activity, thus exhibiting a remarkable reusability. [Copyright &y& Elsevier]

Abstract: A novel supported Pd catalyst was synthesized by using plant tannin grafted collagen fiber as the supporting matrix. The as-prepared Pd catalyst was subsequently used for the catalytic transfer hydrogenolysis of α-methylbenzyl alcohol. Due to the fibrous morphology of collagen fiber and the well dispersed Pd nanoparticles anchored by tannins, the as-prepared Pd catalyst showed superior activity for the catalytic transfer hydrogenolysis of α-methylbenzyl alcohol when compared with the Pd catalyst supported on inorganic oxides. Moreover, the as-prepared Pd catalyst can be reused at least 6 times without significant loss of activity and selectivity, suggesting a satisfied reusability. [Copyright &y& Elsevier]

[Display omitted] • Catechol-based lignin oligomers showed excellent self-assembly ability. • In situ synthesis of Pd/LNPs was achieved on LNPs with phenolic hydroxyl groups. • Pd/LNPs-catalyzed selective hydrogenation of lignin-derived aldehydes into alcohols. • Lignin utilization was achieved with multi-scale from lignin oligomers to monomers. With an abundance of oxygen-containing groups on the hydrophilic shell of lignin nanoparticles (LNPs), this biomaterial can serve as a catalytic support to adsorb and load metals. Herein, catechyl lignin oligomers from castor seed coats (Cas) were extracted via solvothermal pretreatment and prepared as LNPs using the solvent shifting method. Pd2+ ions were then stabilized and reduced in situ on the surface of LNPs, which were further utilized for the catalyzed hydrogenation of lignin-derived aldehydes. Due to the homogeneous building units and linear linkages, the lignin oligomers from Cas exhibited superior self-assembly capacity with a lower π-π interaction energy than those from conventional lignocelluloses, resulting in a high yield of LNPs with a smooth surface. The high content of phenolic hydroxyl groups in catechyl-dominant LNPs resulted in efficient Pd2+ ions adsorption via chemisorption of monomolecular layer and a partial reduction of the Pd2+ ions into metallic states. In addition, the Cas- derived Pd/LNPs exhibited exceptional catalytic activity for the hydrogenation of lignin-derived aldehydes with high selectivity to alcohols under mild conditions. This could be attributed to the interaction preference of the reaction substrate according to the construction of LNPs: strong hydrogen bond between the aldehyde group of the substrate and the hydrophilic shell of LNPs, as well as the hindered π-π interactions between the benzene ring of the substrate and the hidden hydrophobic core of LNPs. This study, therefore, successfully employed lignin with a broad range of molecular weights from oligomers to monomers, paving the way for a comprehensive lignin biorefining industry. [ABSTRACT FROM AUTHOR]

Graphical abstract Leather, the evolved version of thermal insulation materials from animal hides, is one of the oldest but still popular natural clothing materials. Herein, we develop a multifunctional thermal camouflage armor by direct editing the natural insulation structure of leather. The armor simultaneously exhibits exceptional thermal and non-thermal functionalities, including persistent camouflage performance, hydrophobicity, flame-resistance and arbitrary tailorability. Highlights • Leather enables the synthesis of multifunctional thermal camouflage armor. • Thermal convection, conduction and radiation are suppressed simultaneously. • The armor exhibits persistent camouflage performances. • Non-thermal functionalities are also provided. Abstract Realizing persistent thermal camouflage of heat objects remains challenging. A variety of biological species have evolved extraordinary thermal insulation strategies that represent an exciting source of inspiration for developing high-performance thermal camouflage materials. However, we are still far from being able to faithfully mimic these natural insulation materials not only because of the difficulty to imitate the intricate structural hierarchy but also due to the challenge to simulate the way used by nature, that is, each level of structural hierarchy collaborates together to achieve efficient insulation. Instead of biomimicing the biological structures, we here make a direct structure editing on the natural insulation structure of cowhide for obtaining multifunctional thermal camouflage armor. SiO 2 nanoparticles (SiO 2 NPs) were in situ grown on the 3D hierarchically fibrous scaffold of leather, which played multiple roles in trapping stagnant air as thermal insulator, blocking infrared absorptive groups and reflecting infrared radiation from heat objects. The thermal camouflage armor exhibited a high porosity to 61.4%, as well as low thermal diffusivity (1.24 × 10−7 m2 s−1) and thermal conductivity (0.04 W m−1 K−1). The thermal camouflage armor exhibited persistent camouflage performance (1.0 h) and exceptional non-thermal functionalities, including hydrophobicity, flame-resistance, flexibility and arbitrary tailorability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Barbican strategy was proposed to construct advanced X -ray shielding materials. • Barbican-inspired core–shell nanoparticles were assembled and incorporated into natural leather. • Core-shell structure particles elevate the shielding capability of ∼10% compared to merely mixing two elements. • Obtained materials display superior physiomechanical properties to the Chinese National Standard. With the wide application of X -rays, the development of flexible and efficient radiation protective materials to reduce the hazards of radiation is in great demand. Inspired by the Barbican defense system, the bimetallic nanocomposites were designed and assembled to trap X -rays photons to experience ordered and cyclic attenuation behavior, where two high-atomic-number elements with different absorption edges, Bismuth (Bi) and Tin (Sn), are assembled into a core–shell nanostructure (Bi@Sn) and were then evenly dispersed into natural leather (NL) to fabricated a high-efficiency wearable radiation protective material (Bi@Sn/NL). Benefiting from the well-defined Barbican-effect mechanism of the core–shell nanostructure, Bi@Sn nanoparticle features more efficient X -ray shielding capability than Bi+Sn nanoparticles mixtures which directly mixed Bi and Sn, and a 2.0 mm-thick Bi 2.31 @Sn 2.43 /NL could achieve a comparable attenuation efficiency to a 0.25 mm lead plate and averagely exceeded ∼10.4% than Bi 2.31 +Sn 2.43 /NL. Furthermore, Bi 2.31 @Sn 2.43 /NL also displays superior physiomechanical properties to the requirements of the Chinese National Standard and features an ultralow density of 1.2876 g cm−3. This work is expected to provide a promising strategy for the design and development of lightweight and high-efficiency wearable radiation protective materials. [ABSTRACT FROM AUTHOR]

Abstract: Black wattle tannin (BT), a typical natural plant polyphenol, was grafted onto collagen fiber (CF) to act as the stabilizer and carrier of Pd nanoparticles, and as a result, a recyclable heterogeneous Pd catalyst (Pd-BT-CF) was synthesized. The main physicochemical properties of the Pd-BT-CF catalyst were characterized by Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), and Transmission Electron Microscopy (TEM). It was found that the catalyst was in an ordered fibrous state, on which Pd nanoparticles with diameter of 4nm were highly dispersed. Subsequently, the Pd-BT-CF catalyst was employed for the hydrogenation of quinoline. The influences of reaction time, temperature, H2 pressure and solvent on the catalytic hydrogenation of quinoline were systematically investigated. The experimental results suggested that the Pd-BT-CF catalyst exhibited high catalytic activity and selectivity for quinoline hydrogenation. The average turnover frequency (TOF) of Pd-BT-CF was as high as 165.3molmol−1 h−1, and the selectivity to 1,2,3,4-tetrahydroquinoline was 100% when the reaction was carried out at 60°C and 2.0MPa for 1.0h. Moreover, the activity and selectivity of Pd-BT-CF catalyst were not significantly reduced after being reused 6 times, exhibiting a satisfied reusability. Further XPS, Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and TEM analyses confirmed that the Pd species were stabilized by the hydroxyls of BT-CF, which prevented the aggregation and leakage of Pd during the reaction. [Copyright &y& Elsevier]

Abstract: Thermo-sensitive polyurethane (TSPU) solution containing varying concentration of in situ-generated TiO2 nanoparticles was successfully prepared via an organic–inorganic hybrid technique, and the final nanocomposite membranes were formed via solution casting. Depending on the membrane formation temperature (Tmf ) during casting, completely-opposite gas transport behaviors of the TSPU nanocomposite membranes were observed. When Tmf was lower than the melting point (Tm ) of soft segment (PCL10000) in the TSPU, gas permeability coefficients of the nanocomposite membranes were found to increase significantly with increasing nano-TiO2 concentration. Conventional composite theory failed to explain such observation because filler particles are generally considered to create more tortuous diffusion path in the polymer for penetrants, and should thereby lead to a systematic reduction in gas permeability. This counter-intuitive phenomenon was then rationalized by postulating that rigid TSPU chain could not pack efficiently around the TiO2 nanoparticles during solvent evaporation, which resulted in polymer layer with higher free volume at the interface than the bulk polymer regions. Evidences supporting such presumption were provided by (1) density measurement that found negative deviation of actual densities of TSPU nanocomposite membranes from theoretical prediction; (2) positron annihilation lifetime spectroscopy that demonstrated increased free-volume size and concentration within TSPU upon the in situ generation of TiO2 nanoparticles. However, when Tmf was elevated above the Tm of the soft segment, flexible TSPU chain seemed able to pack around the TiO2 nanoparticles as efficiently as in the bulk polymer. In this case, gas transport behavior of the TSPU nanocomposite membranes followed the prediction of conventional composite theory. [Copyright &y& Elsevier]

Abstract: The aim of this study is to use collagen fiber (CF) as a natural polymeric support to synthesize a novel palladium (Pd) nanoparticle catalyst. To achieve a stable immobilization of Pd on CF support, epigallocatechin-3-gallate (EGCG), a typical plant polyphenol, was grafted onto CF surface, acting both as dispersing and stabilizing agent for Pd nanoparticles. Scanning electron microscopy showed that this catalyst was in ordered fibrous state with high flexibility. The presence of EGCG grafted on CF and the interaction mechanism of Pd ions with support was investigated by X-ray photoelectron spectroscopy. X-ray diffraction and transmission electron microscopy offered evidence that the well-dispersed Pd nanoparticles were generated on the outer surface of CF. By using the hydrogenation of allyl alcohol as a model reaction, the synthesized catalyst presented remarkably improved activity, selectivity and reusability as compared with the Pd catalyst supported by CF without grafting of EGCG. [Copyright &y& Elsevier]

Abstract: Bayberry tannin (BT), a natural plant polyphenol, was used as a stabilizer to prepare supported platinum catalysts. Bayberry tannin was first grafted onto aminated SiO2 beads and subsequently coordinate with Pt(IV) species. Then a series of heterogeneous Pt–bayberry tannin–SiO2 (Pt–BT–SiO2) catalysts was obtained after reduction with NaBH4. The catalysts were characterized by UV–DR, XRD and TEM, and the coordination state of Pt(IV) with BT grafted on SiO2 beads was investigated by XPS. It was found that the Pt–BT–SiO2 catalysts were highly active and stable in aqueous hydrogenation of acrylic acid, α-methacrylic acid, allyl alcohol and 2-methyl-3-buten-2-ol. Moreover, the Pt–BT–SiO2 catalysts could be conveniently recovered from the reaction systems simply by filtration, and be reused at least five times without loss of activity. [Copyright &y& Elsevier]

Abstract: A novel heterogeneous palladium (Pd) nanoparticle catalyst stabilized by collagen fibers (CF) was synthesized. Epigallocatechin-3-gallate (EGCG), a typical natural polyphenol, was grafted onto the CF surface to improve the stabilization and immobilization of Pd(0) nanoparticles. The main physical and chemical properties of the catalyst were characterized by means of Scanning Electron Microscopy, Fourier Transform-Infrared Spectroscopy, X-ray Photoelectron Spectroscopy, X-ray Diffraction and Transmission Electron Microscopy. This catalyst is in an ordered fibrous state with high flexibility. The Pd(0) nanoparticles with diameters of 3–4nm are homogeneously dispersed onto the outer surfaces of CF, and they are stabilized by the coordinative interactions between the surface Pd atoms of nanoparticle and the surrounding oxygen and nitrogen atoms of the EGCG-grafted CF. These stabilized Pd(0) nanoparticles were found to be active and selective catalysts for nitrobenzene and its derivatives, directly hydrogenating to the correspondingly reductive anilines under mild conditions. Both Pd particle size and activity of the catalyst showed a marked dependence on the grafting degree of EGCG on CF. These catalysts can be easily recovered, reused multiple times, and stored for two months in air while maintaining high catalytic efficiencies. All these facts suggest that the EGCG-grafted CF can be used as an effective stabilizer for the preparation of Pd(0) nanoparticle catalysts. [Copyright &y& Elsevier]