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Separator is an essential component of lithium-ion batteries (LIBs), which is placed between the electrodes to impede their electrical contact and provide the transport channels for lithium ions. Traditionally, the separator contributes the overall mass of LIBs, thereby reducing the gravimetric capacity of the devices. Herein, a dual-layer redox-active cellulose separator is designed and fabricated to enhance the electrochemical performances of LIBs by introducing NiS. The presented separator is composed of an insulating bacterial cellulose (BC) nanofiber layer and a conductive, and redox-active NiS@BC/carbon nanotubes layer. By using the NiS@BC separator, the discharge capacity of the LiFePO4//Li half battery is enhanced to 117 mAh g-1 at a current of 2C owing to the redox-activity of NiS. Moreover, the functional separator-electrode interface can facilitate the homogenous Li stripping/plating and depress the polarization upon the repeated stripping/plating process. Consequently, the battery containing the redox-active separator exhibits outstanding cycle stability and rate capability. The present study contributes a novel strategy for the developments of functional separators to improve the electrochemical properties of LIBs., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cellulose composite nanopaper is extensively employed in flexible energy storage systems owing to their light weight, good flexibility and high specific surface area. Nevertheless, achieving flexible and ultrathin nanopaper supercapacitors with excellent electrochemical performance remains a challenge. Herein, surface cationization of bacterial cellulose (BC) nanofibers was conducted using 2,3-epoxypropyltrimethylammonium chloride (EPTMAC). Anion-doped polypyrrole (PPy) was incorporated onto the surface of the cationic bacterial cellulose (BCE) nanofibers by an interfacial electrostatic self-assembly process. The obtained PPy@BCE electrode exhibited excellent electrochemical performance, including an areal capacitance of 3988 mF cm -2 at 1.0 mA cm -2 and a capacitance retention of 97 % after 10,000 cycles. A laminated paper-forming strategy was adopted to design and fabricate all-in-one integrated flexible supercapacitors (IFSCs) using PPy@BCE nanopaper as electrodes and BC nanopaper as a separator. The IFSCs showed superior areal capacitance (3669 mF cm -2 at 1 mA cm -2 ), high energy density (193.7 μWh cm -2 at a power density of 827.3 μW cm -2 ), and outstanding mechanical flexibility (with no significant capacitance attenuation after repeatedly bending for 1000 times). The present strategy paves a way for the large-scale production of paper-based energy storage devices., Competing Interests: Declaration of competing interest There is no conflict of interest for this manuscript., (Copyright © 2023. Published by Elsevier B.V.)

Hydrothermal degradation was used to pretreat terylene with an aim of noticeably improving the yield of fermentable monomers: terephthalic acid (TPA), mono (2- hydroxyethyl) terephthalic acid (MHET), bis-hydroxyethyl terephthalate (BHET), and ethylene glycol (EG). After 0.5 h of reaction time at 180 °C, hydrothermal degradation with ammonia led to almost complete conversion of the terylene to TPA, MHET, BHET and EG, which were then transformed by Taonella mepensis WT-6 to bacterial cellulose (BC). Furthermore, the optimum fermentation conditions with the maximum BC yield were 5.0 g/L yeast extract, 30.0 °C, pH 9.0, 8.0% inoculum, and hydrolysate TOC (5.02 g/L). Additionally, mechanical and thermal analysis revealed that the properties of BC produced from TAH medium were similar to those of BC produced with HS medium. Considering the substantial amount of global terylene waste being produced, this study provides an alternative solution for the biosynthesis of BC., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A major challenge to large-scale production and utilization of bacterial cellulose (BC) for various applications is its low yield and productivity by bacterial cells and the high cost of feedstock. A supplementation of the classical expensive Hestrin and Schramm (HS) medium with 1 % polyethylene terephthalate ammonia hydrolysate (PETAH) resulted in 215 % high yield. Although the physicochemical properties of BC were not significantly influenced, the BC produced in 1 % PETAH-supplemented HS medium showed a higher surface area, which showed 1.39 times higher adsorption capacity for tetracycline than BC produced in HS medium. The 1 % PETAH-supplemented HS medium respectively enhanced the activity of α-UDP-glucose pyrophosphorylase and α-phosphoglucomutase by 30.63 % and 135.24 % and decreased the activity of pyruvate kinase and phosphofructokinase by 40.34 % and 52.63 %. The results of this study provide insights into the activation mechanism of Taonella mepensis by PETAH supplementation for high yield and productivity of BC. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, bacterial cellulose (BC) with antimicrobial properties was produced from waste jasmine flower through sequential fermentations with the fungus Trichoderma reesei and the bacterium Taonella mepensis. In this process, waste jasmine flower was first used for producing cellulase and xylanase with Trichoderma reesei. The activities of cellulase and xylanase in waste jasmine flower reached 66.54 U/g and 107.25 U/g, respectively. Waste jasmine flower was hydrolyzed enzymatically on-site and the resulting hydrolysate was used for BC production. The highest BC yield from supplemented jasmine flower hydrolysate (SJFH) was 4.78 g/L, 2.1 times higher than that from Hestrin and Schramm (HS) medium. BC samples were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, field emission scanning electron microscopy, and antibacterial analysis. The results showed that both the nano structure and thermal property of BC from SJFH medium (BC-JF) were similar to those of BC from HS medium (BC-HS). Furthermore, BC-JF composite displayed excellent antibacterial activity against Staphylococcus aureus. Considering the good biocompatibility of BC-JF to human umbilic vein endothelial cells, this antibacterial BC-JF, which was bioconverted from waste jasmine flower, shows great medical and pharmaceutical application potential. [Display omitted] • Functional bacterial cellulose (BC) was synthesized from waste jasmine flower. • This process is green and cheap. • Jasmine flower hydrolysate significantly improved BC yield. • BC from jasmine flower showed antibacterial activity against S. aureus and E. coli. • BC from jasmine flower demonstrated excellent biocompatibility. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy)/cellulose nanofiber (CNF) composites have been widely used in flexible energy storage devices because of their lightweight, inherent mechanical flexibility and large specific surface area. However, it is still a challenge to obtain PPy/CNF composite electrodes with high cycling stability. Herein, an electrostatic self-assembly strategy was adopted to deposit anion-doped PPy onto cationic poly(methacryloxyethyltrimethyl ammonium chloride)-grafted bacterial cellulose (BCD) nanofibers. The optimized PPy@BCD electrode demonstrated a high areal capacitance of 6208 mF cm−2 at a current density of 0.5 mA cm−2 and superior cycling stability (a capacitance retention of 100 % after 10,000 charge-discharge cycles at 10 mA cm−2). A quasi-solid-state anti-freezing flexible supercapacitor (AF-FSC) was designed by employing polyacrylamide organohydrogel electrolyte, yielding an areal capacitance of 2930.6 mF cm−2 at 1 mA cm−2 and a capacitance retention of 92.2 % after 1000 cycles at −20 °C. The present AF-FSC is expected to serve as a power source in real-life low-temperature applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of BC/BF adsorbent for the first time through co-fermentation. • High PNP adsorption potential of BC/BF composite. • Pore filling, electrostatic interaction, and hydrogen bonding all involved in PNP adsorption. • Renewability and reusability of BC/BF adsorbent. Polyethylene terephthalate (PET) nano-plastics (PNP) is a major source of water pollution which in turn causes health issues in humans. There is no effective method to completely remove PNP from wastewater. In this study, bacterial cellulose (BC)/bacterial flocculant (BF) composite was produced from PNP ammonia hydrolysate through the co-cultivation of Taonella mepensis WT-6 and Diaphorobacter nitroreducens R9. The structural characterization of the BC/BF composite through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and thermal and mechanical analyses demonstrated that the amino-group-rich flocculant produced by the D. nitroreducens R9 was incorporated into the BC network without interfering the self-aggregation of cellulose fibrils. Fast PEP removal was observed in pure and tap water with maximum sorption capacity (Qmax) of 124.65 mg/g and 115.60 mg/g, respectively, whereas least removal was observed for campus lake water with a Qmax value of 84.78 mg/g. A 10 mM SO 4 2− significantly decreased the adsorption capacity to 44.52 mg/g, while 2 mM Ca2+ contributed to the adsorption of PNP with a maximum adsorption capacity of 144.78 mg/g at pH 6.0. The potential adsorption mechanism was investigated through adsorption kinetic studies, isothermal models, and thermodynamics studies. The adsorbed BC/BF was recycled by desorbing PNP with ammonia water, and the eluent could be utilized as a medium for sustainable production of BC/BF. The reusable BC/BF adsorbent produced through the co-culture technique can effectively control PNP pollution. [ABSTRACT FROM AUTHOR]

Polymeric materials doped with SiC particles can exhibit promising nonlinear properties that can be widely used in electrical field grading applications. However, excellent field-grading performance is at the expense of mechanical characteristics due to excess fillers in the composites. Therefore, how to realize synergistic optimization of electrical and mechanical performances in ultra-low SiC loading is urgent for practical applications. In this study, we report a novel strategy to achieve comprehensive enhancement of thermal, mechanical and electrical properties of epoxy composites with self-assembly surface-modified SiC particles on cellulose aerogel scaffolds. The composites exhibit excellent nonlinear electrical properties at a low SiC loading of 4.47 vol%, and introducing different volume fractions of SiC into cellulose aerogel supported epoxy composites can largely broaden the range of switching field. Meanwhile, the dynamic mechanical test reveals that the storage modulus and crosslinking density of the composites are markedly enhanced due to 3D interconnected structure, while the thermal conductivity of this composite is also notably improved by about 300%. This method provides a novel idea for electric field grading composites with concurrent reinforcement performances in potential applications. [Display omitted] [ABSTRACT FROM AUTHOR]