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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]

In order to obtain high-flux antifouling nanofiltration membrane, a series of ICIC/ZnO/HBPA nanofiltration membranes were prepared by interfacial polymerization of 5-isocyanato-isophthaloyl chloride (ICIC) and hyperbranched polyamide (HBPA) on the surface of polyacrylonitrile (PAN) ultrafiltration membrane, the nano-ZnO was incorporated into the polyamide separation layer. The existence of ZnO is confirmed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The analysis results of water contact angle indicate that the membrane hydrophilicity is increased by incorporation of ZnO nanoparticles, the lowest water contact angle of the membrane is 22.7°. Compared with the membrane without ZnO, the flux and the salt rejection rate for NaCl, MgCl2, Na2SO4 and MgSO4 of the membrane containing ZnO increase. The largest flux of the ICIC/ZnO/HBPA membrane is about 102 L·m-2·h-1, which is nearly 2.6 times of the membrane without ZnO. The bacteriostasis of the membranes to E. coli is enhanced by incorporation more ZnO. Increasing the monomer content or prolonging the interfacial polymerization time is beneficial to increasing the salt rejection rate, but the order of the salt retention rate is changed. When HBPA is 0.8%, ICIC is 0.1%, content of ZnO is 0.02 g and reaction time is 10 min, the salt rejection rate for NaCl, MgCl2, Na2SO4 and MgSO4 of the prepared membrane are 60.8%, 96.4%, 95.1%, 96.7% and the flux is 53, 54.7, 53.7 L·m-2·h-1and 54.7 L·m-2·h-1, respectively.

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]

Hepatocellular carcinoma (HCC), the third leading cause of cancer deaths worldwide, is most commonly caused by chronic hepatitis B virus (HBV) infection. However, whether HBV plays any direct role in carcinogenesis, other than indirectly causing chronic liver injury by inciting the host immune response, remains unclear. We have established two independent transgenic mouse lines expressing the complete genome of a mutant HBV ("preS2 mutant") that is found at much higher frequencies in people with HCC than those without. The transgenic mice show evidence of stress in the endoplasmic reticulum (ER) and overexpression of cyclin D1 in hepatocytes. These mice do not show any evidence of chronic liver injury, but by 2 years of age a majority of the male mice develop hepatocellular neoplasms, including HCC. Unexpectedly, we also found a significant increase in hepatocarcinogenesis independent of necroinflammation in a transgenic line expressing the entire wildtype HBV. As in the mutant HBV mice, HCC was found only in aged--2-year-old--mice of the wildtype HBV line. The karyotype in all the three transgenic lines appears normal and none of the integration sites of the HBV transgene in the mice is near an oncogene or tumor suppressor gene. The significant increase of HCC incidence in all the three transgenic lines--expressing either mutant or wildtype HBV--therefore argues strongly that in absence of chronic necroinflammation, HBV can contribute directly to the development of HCC.

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]