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Solid polymer electrolytes (SPEs) have gained remarkable development within the realm of new energy resources. With its improved electrochemical stability and environmental‐friendly sustainability, bacterial cellulose (BC) has emerged as a promising candidate for applications in SPEs. Herein, bacterial cellulose was chemically cyanoethylated and integrated with lithium bis(trifluoromethanesulphonyl)imide/polyethylene oxide (PEO) based SPE. Some vertical channels are formed when trace amounts (0.5 wt%) of cyanoethylated bacterial cellulose (BC‐CN) are added to PEO‐based SPE, as revealed by SEM. This formula's corresponding PEO‐based SPE presents the highest ion conductivity of 5.7 × 10−4 S cm−1 at 60°C. The ion migration activation (Ea) deduced from the Arrhenius equation is 0.48 eV, lower than the value of 0.82 eV for the pristine PEO SPE. Besides, the Li+ migration number of this modified PEO‐based solid electrolyte is calculated to be a relatively high value of 0.33, while that of its counterpart, the pristine PEO SPE, is as low as 0.06. The all‐solid‐state lithium battery with PEO/0.5%BC‐CN SPE can operate stably for 115 cycles, which is longer than the 80 cycles achieved with the pristine PEO SPE. This study introduces a novel strategy for creating modified BC composites PEO‐based SPE. Highlights: Bacterial cellulose was chemically cyanoethylated.Cyanoethylated bacterial cellulose composite polyethylene oxide (PEO)‐based solid polymer electrolytes (SPEs) are prepared in DMF.Opening pores penetrate the surface of the PEO/0.5% cyanoethylated bacterial cellulose (BC‐CN) SPE membrane.PEO/0.5% BC‐CN shows ionic conductivity of 5.7 × 10−4 S cm−1 at 60°C.Full cell with PEO/0.5% BC‐CN performs stably for 115 cycles. [ABSTRACT FROM AUTHOR]

It is still a challenge to synthesize high-performance adsorbents for uranium extraction from seawater. The stable uranyl tricarbonate complex in seawater seems to preclude coordination of uranyl ions by adsorbents. This study reports 3D networked colloidal particles consisting of polyamidoxime (PAO) and sodium polyacrylate (PAA-Na) segments via competitive conversion between amidoximation and hydrolysis in NaOH aqueous solutions. PAA-Na can promote the dissociation of uranyl ions via ion exchange for high-efficiency coordination by PAO. As a result, the colloidal particles, with high selectivity for uranyl ions, reach an outstanding uranium uptake capacity of 17.8 mg U per g in real seawater after 20-day adsorption. [ABSTRACT FROM AUTHOR]

The confinement and high utilization of sulfur in the cathodes is critical for improved cycling performance of lithium‐sulfur batteries. In this case one‐pot hydrothermal strategy is developed to produce rGO/MXene/sulfur composite aerogels where sulfur is in situ trapped in the 3D rGO/MXene conductive skeleton. The optimized composite aerogels as free‐standing cathodes delivery a specific capacity of 951 mAhg−1 after 100 cycles at 0.2 C with a low fading rate of 0.062 % per cycle. The excellent cycling performance is correlated with highly oxidized MXene and in situ formed sulfate/thiosulfate complex layer in the long‐term cycles. [ABSTRACT FROM AUTHOR]

A heterostructure composed of ZIF-67-derived nitrogen and cobalt-doped carbon enfolded silicon (C@Si) nanoparticles anchored on 2D MXene layers was constructed for boosting the performance of lithium-ion batteries (LIBs). The heterostructure anode demonstrated a high initial discharge capacity of 3021 mA h g−1 at 0.2 A g−1, retaining outstanding cycling stability with a reversible capacity of 520 mA h g−1 at 2000 mA g−1, and the coulombic efficiency remained above 97% after 500 cycles. The introduced Ti3C2 nanosheets and the cobalt-doped carbon can not only contribute to the interfacial transfer of Li+ and electrons but also buffer the volume expansion of Si. [ABSTRACT FROM AUTHOR]

In lithium batteries, composite solid electrolytes gain their reputation owing to their great safety, excellent mechanical properties, and remarkably improved electrochemical performance. Herein, composite polyethylene oxide (PEO)‐based solid electrolytes with well‐dispersed in situ polydopamine‐coated lithium montmorillonite (PDA@LiMMT) nanofillers are successfully fabricated. The involvement of PDA@LiMMT retards significantly the crystallization of PEO, addressing a manifest enhancement in the ionic conductivity of the modified composite solid electrolyte. A conducive ionic conductivity value of 3.06 × 10−4 S cm−1 at 60 °C is reached, while the electrochemical window widens to 4.7 V. The assembled Li/solid polymer electrolytes/LiFePO4 battery exhibits a 158.2 mA h g−1 high discharge specific capacity at a current density of 0.5C; besides, the capacity retention rate keeps 86% after 200 cycles. The enhancement of the cycle stability of the solid‐state batteries highlights the excellent interfacial stability between the modified solid electrolytes and the lithium electrode, which originates from lithiophilicity of PDA. [ABSTRACT FROM AUTHOR]

Adsorption‐photocatalysis technology based on covalent organic frameworks (COFs) offers an alternative method for advancing the field of uranium extraction from seawater. When determining the photocatalytic activity of COFs, the binding energy of excitons (Eb) functions is the decisive factor. Nevertheless, the majority of reported COFs have a large Eb, which seriously restricts their application in the field of photocatalysis. Using a practical π‐skeleton engineering strategy, the current study synthesizes three donor‐acceptor olefin‐linked COFs containing amidoxime units in an effort to minimize Eb. Theoretical and experimental results reveal that the construction of planar and continuous π‐electron delocalization channels can significantly reduce Eb and promote the separation of electron‐hole pairs, thereby enhancing the photocatalytic activities. Moreover, the Eb of the TTh‐COF‐AO with a planar π‐skeleton donor is significantly reduced, and exhibits a substantially smaller Eb (38.4 meV). Under visible light irradiation, a high photo‐enhanced uranium extraction capacity of 10.24 mg g−1 is achieved from natural seawater without the addition of sacrificial reagents, which is superior to the majority of olefin‐linked COFs that have been reported to date. This study, therefore, paves the way for the development of tailored, efficient COFs photocatalysts for the extraction of uranium from seawater. [ABSTRACT FROM AUTHOR]

The mesophase in the as-stretched poly(L-lactide) (PLLA) exhibits low thermal stability and undergoes melting around [T.sub.g]. As a consequence, without constraints as-stretched PLLA can recover to its original (unstretched) length while being held above [T.sub.g]. Upon constrained annealing at 70 °C mesophase is transformed into highly oriented crystals, responsible for little free shrinkage and superior dimensional stability. At the same time, molecular orientation in the amorphous phase first decreases significantly due to thermodynamic relaxation, and then increases moderately with the advent of cold crystallization. It correlates well with the change of yield strength with respect to annealing time. POLYM. ENG. SCI., 53:2568-2572, 2013. © 2013 Society of Plastics Engineers, INTRODUCTION Poly(L-lactide) (PLLA), derived from renewable resources, is one of the most attractive biodegradable polyesters (1), (2). Similar to other polyesters, such as poly(ethylene terephthalate) (3), (4), the crystallization rate [...]

The effect of amorphous poly(D, L-lactide) (PDLLA) on the molecular orientation and crystallization of crystalline poly(L-lactide) (PLLA) on stretching is reported in this study. It is indicated that the presence of PDLLA in its miscible blends with PLLA is not favorable for either cohesive mesophase formation below [T.sub.g] or strain-induced crystallization above [T.sub.g] at strains beyond the segmental extensibility limit. Because of lack of constraints imposed by cohesive mesophase or crystals, oriented segments are liable to slide each other or recoil, responsible for low-molecular orientation in the stretched blends. POLYM. ENG. SCI., 53:21-26, 2013.[C] 2012 Society of Plastics Engineers, INTRODUCTION Polylactide (PLA) is a kind of biodegradable polyester derived from renewable sources and has good biocompatibility, mechanical properties, and processing ability (1-4). As a chiral polymer, structural formation of [...]

To improve the toughness of isotactic polypropylene (iPP), by blending modification or special processing techniques, is an ongoing pursuit in the polymer community. In this study, the toughness of injection-molded iPP bars has been enhanced by about four times upon annealing at 140 C, in parallel with slight increasing of stiffness. Through various structural characterizations it has been confirmed that the remarkable toughening effect in the annealed iPP bars mostly results from the enhanced molecular mobility in the amorphous phase due to lamellar perfection, rather than from the change of molecular orientation, crystal modification, crystallinity, and so on. Moreover, it is deduced that the gain of mobile amorphous fraction in the hierarchical iPP bars upon annealing follows the order of skin > intermediate > core, same to that contributing to the toughness enhancement. POLYM. ENG. SCI., 52:893-900, 2012. © 2011 Society of Plastics Engineers, INTRODUCTION Injection molding is a popular processing method of thermoplastic polymers, which pushes the melt under force into a cold mold to form solid parts. It is well known that [...]