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Highlights: [•] Ultrasonic pretreatment lipase-catalyzed synthesis of 4-methoxy cinnamoyl glycerol (4MCG) was studied. [•] The enzymatic method using ultrasonic pretreatment significantly improved overall esterification reaction rate and monoester (4MCG) yield. [•] The ultrasonic pretreatment process did not damage the lipase activity. [Copyright &y& Elsevier]

Abstract: A solid base catalyst Na2SiO3 was prepared by microwave heating. The catalyst was used to catalyze the transesterification reactions for the production of fatty acid methyl esters from cottonseed oil. The optimum conditions of the catalyst preparation and transesterification reactions were investigated by orthogonal experiments. The catalyst with the highest catalytic activity was obtained using microwave power of 640 W, microwave irradiation time of 6 min, catalyst particle size of 60 mesh. The catalyst was characterized with X-ray diffraction (XRD), scanning electron micrographs (SEM), and the results showed the catalyst Na2SiO3 has good microstructure. Under the transesterification conditions of methanol/oil molar ratio of 6:1, catalyst dosage of 5%, reaction temperature of 65 °C, reaction time of 100 min and stirring speed of 400 rpm, the yield of methyl esters was 97.6%. The lifetime of the solid base catalysts by different process methods (microwave heating and conventional electric heating) was no significant differences, but microwave heating may be more economical than conventional electric heating. [Copyright &y& Elsevier]

Abstract: A novel production process of biodiesel using magnetically stabilized fluidized bed reactor (MSFBR) has been developed based on cottonseed oil and the reaction conditions were also studied. The reactant flow rate and magnetic field intensity affects on the magnetic catalytic particles behavior in the column were performed, and the transesterification reaction conditions of cottonseed oil were investigated in MSFBR with nanometer magnetic catalytic particles. Under the suitable reaction conditions of methanol/oil molar ratio 8:1, 40 cm3 min−1 flow rate, 225 Oe magnetic field intensity and temperature of 65 °C, the conversion efficiency reaches to 97% in 100 min. The stability and recovery of the magnetic catalytic particles in MSFBR are much better than that in autoclave stirred reactor. The result shows that most of the resultant cottonseed oil biodiesel parameters comply with the limits established by representative biodiesel standards. [Copyright &y& Elsevier]

The quest for smart electronics with higher energy densities has intensified the development of high‐voltage LiCoO2 (LCO). Despite their potential, LCO materials operating at 4.7 V faces critical challenges, including interface degradation and structural collapse. Herein, we propose a collective surface architecture through precise nanofilm coating and doping that combines an ultra‐thin LiAlO2 coating layer and gradient doping of Al. This architecture not only mitigates side reactions, but also improves the Li+ migration kinetics on the LCO surface. Meanwhile, gradient doping of Al inhibited the severe lattice distortion caused by the irreversible phase transition of O3−H1−3−O1, thereby enhanced the electrochemical stability of LCO during 4.7 V cycling. DFT calculations further revealed that our approach significantly boosts the electronic conductivity. As a result, the modified LCO exhibited an outstanding reversible capacity of 230 mAh g−1 at 4.7 V, which is approximately 28 % higher than the conventional capacity at 4.5 V. To demonstrate their practical application, our cathode structure shows improved stability in full pouch cell configuration under high operating voltage. LCO exhibited an excellent cycling stability, retaining 82.33 % after 1000 cycles at 4.5 V. This multifunctional surface modification strategy offers a viable pathway for the practical application of LCO materials, setting a new standard for the development of high‐energy‐density and long‐lasting electrode materials. [ABSTRACT FROM AUTHOR]

The quest for smart electronics with higher energy densities has intensified the development of high‐voltage LiCoO2 (LCO). Despite their potential, LCO materials operating at 4.7 V faces critical challenges, including interface degradation and structural collapse. Herein, we propose a collective surface architecture through precise nanofilm coating and doping that combines an ultra‐thin LiAlO2 coating layer and gradient doping of Al. This architecture not only mitigates side reactions, but also improves the Li+ migration kinetics on the LCO surface. Meanwhile, gradient doping of Al inhibited the severe lattice distortion caused by the irreversible phase transition of O3−H1−3−O1, thereby enhanced the electrochemical stability of LCO during 4.7 V cycling. DFT calculations further revealed that our approach significantly boosts the electronic conductivity. As a result, the modified LCO exhibited an outstanding reversible capacity of 230 mAh g−1 at 4.7 V, which is approximately 28 % higher than the conventional capacity at 4.5 V. To demonstrate their practical application, our cathode structure shows improved stability in full pouch cell configuration under high operating voltage. LCO exhibited an excellent cycling stability, retaining 82.33 % after 1000 cycles at 4.5 V. This multifunctional surface modification strategy offers a viable pathway for the practical application of LCO materials, setting a new standard for the development of high‐energy‐density and long‐lasting electrode materials. [ABSTRACT FROM AUTHOR]

• V 2 O 5 nanobelt arrays are firstly used as the lithiophilic materials. • This Li-V 2 O 5 -NF composite anode displays superior Li stripping/platting behavior. • The LTO/Li-V 2 O 5 -NF cells display superior rate performance and cycling stability. The lithium metal anode has been considered to be an optimal anode material for high-energy-density battery system due to its ultrahigh specific capacity. However, the sharp dendrite growth and infinite volume expansion have significantly impeded its commercial application. Herein, we propose that V 2 O 5 as the lithiophilic substance can be decorated onto 3D stable frameworks to fabricate dendrite-suppressed composite Li metal anodes via a molten Li infusion method. It is demonstrated that the energetic chemical reaction between V 2 O 5 and molten Li together with the capillary effect based on the nanostructure of interconnected V 2 O 5 nanobelt arrays contributes synergistically to the great Li affinity of the V 2 O 5 -Ni foam (V 2 O 5 -NF) host and facilitate the efficient and uniform intake of molten Li into the 3D framework. Benefitting from the homogeneous Li distribution in the framework, the decreased local current density of the electrode and the stable property of the host, dendrite-free Li stripping/plating behavior and alleviated volume fluctuation have been achieved for the Li-V 2 O 5 -NF composite anode. Compared with the bare Li anode, the as-obtained Li-V 2 O 5 -NF composite anode exhibits much stable stripping/plating profiles with low overpotential (~18 mV) for ultralong lifespan (1600 h) at a current density of 1 mA cm−2 in symmetric Li/Li cell. Furthermore, outstanding rate capability and long-term cycling performance (78.8% capacity retention after 500 cycles under 2 C) are obtained in full cells when coupled with Li 4 Ti 5 O 12 (LTO) cathodes, indicating a promising potential for practical application. Moreover, this work demonstrates that using a new lithiophilic material, V 2 O 5 , should be an effective method to construct high stable 3D Li metal anode for Li metal battery. [ABSTRACT FROM AUTHOR]

Transition metal oxides (TMOs)‐based anode materials of high theoretical capacities have been intensively studied for lithium‐ion storage. However, their poor high‐rate capability and cycling stability remain to be effectively resolved. Herein, a novel ion exchange (IE)‐assisted indirect carbon coating strategy is proposed to realize high performance freestanding TMO‐based anodes for flexible lithium‐ion batteries (FLIBs). This approach effectively avoids the possible side reaction of oxide reduction, enhances degrees of graphitization of the carbon coating, and preserves advantageous nanostructure of the starting template, leading to enhanced electrical conductivities, alleviated volume variation induced structural instability, fast lithium‐ion diffusion pathways and enhanced electron transfer kinetics. As a proof of concept, IE‐prepared carbon coated NiO nanosheet arrays with excellent structural and electrochemical stability are developed as freestanding anodes for LIBs and FLIBs, which exhibit outstanding electrochemical performances superior to most state‐of‐the‐art NiO‐based anodes reported in recent years. The product anode delivers a high areal capacity (3.08 mAh cm−2 at 0.25 mA cm−2), outstanding high‐rate capability (1.78 mAh cm−2 at 8 mA cm−2) and excellent cycling stability (over 300 cycles). Further pouch cell tests confirm the excellent flexibility of the freestanding electrode against mechanical deformation with well‐maintained electrochemical performance under folding. [ABSTRACT FROM AUTHOR]

• NiF x @Ni foam was prepared via a succinct fluorination strategy. • LiF-enriched SEI layer can be in-situ formed through the reaction between NiF x and Li +. • Li@NiF x @NF composite anodes exhibit excellent stability in both symmetry battery and full cell. Metallic lithium is considered as the optimal anode material for the high-energy–density rechargeable lithium-based battery. However, the commercial application of Li metal anode is plagued by uncontrollable dendrites growth and unstable SEI layer derived from the nonuniform nucleation and undesired deposition process. Herein, a hybrid 3D porous Ni foam (NF) current collector decorated by nanostructured lithiophilic layer of interconnected NiF x nanosheets is firstly synthesized by a convenient one-step fluorination strategy. Benefiting from superior lithiophilicity, the NiF x nanosheets can successfully decrease the Li nucleation barrier and act as uniformly distributed nucleation sites for inducing the homogeneous Li deposition. In addition, the interconnected morphology of the NiF x nanosheets and the 3D porous structure of the NF effectively reduce the local current density of the electrode and thus alleviate the dendrites formation. Moreover, a LiF-enriched SEI layer in situ generated from the electrochemical reaction also facilitates the smooth Li plating. As a result, this 3D hybrid NiF x @NF current collector demonstrates dendrite-suppressed Li deposition morphology and excellent stripping/plating reversibility, presenting significantly enhanced Coulombic efficiency of ~ 98% over 450 cycles at 1 mA cm−2. Remarkably, symmetric cell with Li@NiF x @NF anode achieves a prolonged cycling lifespan over 1300 h together with a low overpotential of ~ 20 mV at 1 mA cm−2 under the cycling capacity of 1 mAh cm−2. Furthermore, excellent cycling performance and rate capability of the Li@NiF x @NF anode are also realized in full cells when coupled with LiFePO 4 and Li 4 Ti 5 O 12 cathodes. Our work not only provides an expeditious fluorination strategy to construct 3D fluorinated compound but also illustrates the superiority of synergetic design of lithiophilic sites plus LiF-enriched SEI layer for the current collector of Li metal anode. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hetero-structured Mo 2 C-Mo 2 N/C electrocatalyst for polysulfides is proposed. • A facile in-situ synthesis of hetero-structured Mo 2 C-Mo 2 N/C material is developed. • High-performance lithium-sulfur batteries are realized. • The working mechanism of the material is experimentally and computationally probed. Lithium-sulfur batteries (LSBs) are promising electrochemical energy storage devices. However, the shuttle effects and slow conversion kinetics of lithium polysulfides (LiPSs) still impede the practical application of LSBs. Herein, with the assistance of g-C 3 N 4 , a hetero-structured Mo 2 C-Mo 2 N embedded in the nitrogen-doped carbon sheets composite (Mo 2 C-Mo 2 N/C) is facilely in-situ synthesized. The g-C 3 N 4 not only acts as the nitriding reagent for the heterostructure formation, but also is the structure-directing reagent for the formation of two-dimensional structures. More interestingly, Mo 2 C-Mo 2 N/C is also employed as a modifier of separators for LSBs. As evidenced experimentally and theoretically, the hetero-structured Mo 2 C-Mo 2 N exhibits a strong adsorption ability to LiPSs and concurrently offers a built-in electric field inside the heterostructure that ensures the fast conversion of LiPSs, thus significantly suppressing the shuttle effect and accelerating the electrochemical kinetics of LSBs. Therefore, the prepared LSBs with the Mo 2 C-Mo 2 N/C modified separator deliver a discharge specific capacity of 1404 mAh/g at 0.1 C and 660 mAh/g at 4 C, and achieve 1000 stable cycles at 1 C, with a capacity decay rate of only 0.028% per cycle. This study not only provides an efficient strategy for synthesizing hetero-structured materials but also sheds new light on the design of functional separators for high-performance and long-life cycle LSBs. [ABSTRACT FROM AUTHOR]

The linseed gum/cellulose composite hydrogels were successfully fabricated by mixing cellulose and linseed gum solutions dissolved in the NaOH/urea aqueous system and cross-linked with epichlorohydrin. The morphology and structure of the composite hydrogels were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). The swelling ratio and water retention properties were investigated. The results revealed that linseed gum mainly contributed to water adsorption, whereas the cellulose acted as a backbone to strengthen the porous structure. This work provided a simple way to prepare cellulose-based superabsorbent hydrogels, which could be potentially applied as an effective water conservation material in agriculture. [ABSTRACT FROM AUTHOR]

In this work, single crystal LiNi 0.5 Mn 0.3 Co 0.2 O 2 with conformal precise Al 2 O 3 nanofilm coating and Al surface doping is prepared by precise nano coating and doping (PNCD) based by atomic layered deposition (ALD). PNCD process promotes to form a LiAlO 2 -rich surface layer and plays a crucial role on cycling performance and rate capability at high voltages and safety. [Display omitted] • LiAlO 2 -rich nanofilm coating layer on the surface of NCM523 is formed by atomic layer deposition and Al surface doping by post-annealing. • P-NCM523 exhibits excellent rate capability at 4.55 V in a half cell. • P-NCM523 exhibits superior cycling performances at 4.5 V in a pouch cell. Surface and interfacial instability is a critical issue for nickel-based layered oxides LiNi x Co y Mn 1−x−y O 2 (NCM) (x ≥ 0.5) operating at high cut-off voltages (≥4.5 V). In this work, precise nanofilm coating and doping (PNCD), which combines conformal surface coating by atomic layer deposition and Al surface doping by post-annealing, is used to modify the surface structure of NCM523 (P-NCM523). After PNCD, the rate capability of P-NCM523 at 10C is significantly improved to 160.3 mAh/g with a high cut-off voltage (4.55 V). Furthermore, an excellent reversible capacity of 167.5 mAh/g with a capacity retention of 87.4 % is achieved after 800 cycles at 0.5C within 3.0–4.5 V in the pouch cell constructed by P-NCM523 and a commercial graphite anode. Not only does P-NCM523 have a comparable energy density at 4.5 V to that of NCM811 at 4.2 V, but its thermal stability is also much better. Through surface and phase-transition analysis during the electrochemical process, we conclude that PNCD treatment promotes the formation of a LiAlO 2 -rich surface layer and plays a crucial role in high-voltage cycling and safety. By increasing the cut-off voltages of other cathode materials, the PNCD process achieves high energy density while preserving stability. [ABSTRACT FROM AUTHOR]

• Lithiated halloysite nanotubes and networked polymers are used to prepare a cost-effective artificial composite SEI layer. • This nanocomposite artificial SEI layer exhibits excellent electrochemical and mechanical properties. • The NCL-Li composite anode displays superior Li stripping/platting behavior. • The NCL-Li|NCM811 cells display a good cycling stability and promising safety performance. In lithium metal batteries (LMBs), the instability of the solid electrolyte interface (SEI) induced lithium dendrites and dead lithium frequently causes low cyclability and serious safety issues. Thereby, a highly stable artificial SEI layer with excellent lithium-ion mobility is desirable for dendrite-free lithium metal (LM) anodes. Herein, a novel clay/cross-linked network polymer-based artificial SEI layer (named as NCL) is prepared via compositing lithiated halloysite nanotubes (Li-HNTs) and cross-linked network polymers. The obtained NCL exhibits a promising Li+ transference number of 0.39, high ionic conductivity of 6.37 × 10-4 S cm−1 at 20 °C and superb mechanical performance. Benefiting these advantages, Li+ can be uniformly and fast plated/stripped under the protection of NCL, effectively suppressing the formation of lithium dendrites. The NCL-protected LM symmetrical cells can be stably cycled for more than 1000 h and 1100 h at 1 mA cm−2 under cycling capacities of 1 mAh cm−2 and 3 mAh cm−2, respectively. The NCL-Li|Cu half-cells present dendrite-free and reversible Li deposition with a high Coulombic efficiency of 99% for 170 cycles at 0.5 mA cm−2. Moreover, the LiFePO 4 full-cell successfully achieves a good capacity of 115 mAh g−1 with a sensational capacity retention of 97.5% over 800 cycles at 2C. Additionally, 300 mAh LiNi 0.8 Co 0.1 Mn 0.1 O 2 -coupled pouch-cells not only can stably circulate more than 50 cycles, but also can reliably function at repetitive mechanical deformation statuses and at different damage conditions. Therefore, this novel hybrid artificial SEI protective layer with desirable properties shed new light on the practical application of high-performance LMBs. [ABSTRACT FROM AUTHOR]

To construct highly stable Lithium (Li) metal batteries (LMBs), a polyurethane-LiF based artificial protective membrane (APM) is evenly coated onto LM anodes by a facile solution casting method. Owning to the good ionic conductivity and mechanical properties, APM acts as a physical protective isolation layer between electrolytes and LM to alleviate electrolyte decomposition and suppress Li dendrites. By applying the APM modification, the electrochemical performance of LM is dramatically improved. The Li | APM-Cu half-cell stably circulates 120 cycles with a high Coulombic efficiency of above 90% at a current density of 1 mA cm−2 and an area capacity of 1 mAh cm−2. The APM-Li based symmetric cell presents an ultralong life span of over 1500 h at an area capacity of 1 mAh cm−2and a current density of 0.5 mA cm−2. In full-cell tests, the APM-Li | LiFePO 4 configuration maintains a high specific capacity of 120.4 mAh g−1 after 600 cycles with a superior capacity retention of 97.3% at 2C. Additionally, the extraordinary cyclability of APM-Li | Li 4 Ti 5 O 12 full-cell demonstrates the effectiveness and versatility of APM. The scanning electron microscopy studies confirm the APM's suppression effects of Li dendrites. Therefore, this work provides a promising and affordable APM modification strategy to redeem highly stable LMBs. Image 1 • APM-Li is simply prepared through solution cast method. • The APM-Li preparation is facile and cost-effective. • APM-Li shows the impressive ability of restraining Li dendrites. • Both APM-Li based half-cell and full-cells exhibit excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

• The electrochemical property of Li 4 T 5 O 12 electrode can be improved by mixing liquid metal alloy. • The LM-LTO electrode exhibits superior rate and cycling performance. • LM is beneficial to the conductivity improvement of composite electrode. The spinel lithium titanate (Li 4 Ti 5 O 12 , LTO) has attracted special attention for its low cost, stable structure and little safety issue. However, LTO displays a low electronic conductivity, which seriously impedes its practical applications at remarkable rate capability. Herein, to improve the electrochemical properties of LTO, this research constructed a novel composite anode by mixing the GaSn liquid metal (LM) nanoparticles with LTO. The composite anode's phase structure and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical data indicate that LM-LTO electrode delivers a better rate capability (52% retention from 10 mA/g to 500 mA/g) as well as long cyclic stability (76% retention after 1000 cycles at 200 mA/g). Therefore, this work opens a new avenue for fabricating better rate performance and safer lithium ions battery. [ABSTRACT FROM AUTHOR]