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A concentrated dual-salts LiFSI-LiNO 3 /DOL electrolyte was prepared by using LiNO 3 as the inhibitor. The LiF-Li 2 O-oligomers composite SEI layers can efficiently accommodate the rapid plating/stripping of Li metal. A high average Coulombic efficiency of 99.14% was achieved under a large current density of 8.0 mA cm−2. [Display omitted] Developing a high-rate Li metal anode with superior reversibility is a prerequisite for fast-charging Li metal batteries. However, the build-up of large concentration gradients under high current density leads to inhomogeneous Li deposition and unstable passivation layers of Li metal, resulting in lower Coulombic efficiency. Here we report a concentrated dual-salts LiFSI-LiNO 3 /DOL electrolyte to improve the high-rate performance of Li metal anode. Sufficient Li salts help passivate the fresh Li deposition quickly. Further, DOL contributes to the formation of flexible organic layers that can accommodate the rapid volume change of Li metal upon cycling. Li metal in the electrolyte remains stable over 240 cycles with the average Coulombic efficiency of 99.14% under a high current density of 8.0 mA cm−2. [ABSTRACT FROM AUTHOR]

A high concentration gel polymer electrolyte (GPE) was prepared by simply using LiFSI–LiNO3 dissolved in 1,3-dioxolane. The Li‖Li cell achieves stable battery cycling for over 3200 h. Furthermore, the Li‖Cu cell demonstrates a high CE of 99.2%. Even at a high current density of 8 mA cm−2, a high CE of 98.5% was still achieved. Notably, in a Li‖LiFePO4 cell, this electrolyte enables high capacity retention of 94.5% and an average CE of 99.8% over 500 cycles, showing promising prospects for high-performance lithium metal batteries. [ABSTRACT FROM AUTHOR]

An air-stable Na0.67Mn0.7Cu0.15Ti0.15O2 (NMCT) has been synthesized using a solid-state method. It displays a reversible capacity of 170 mA h g−1 and a capacity retention of 82.5% after 300 cycles. NMCT also exhibits good structural stability upon electrochemical de/intercalation processes as observed by operando XRD. And the result shows that the unit-cell volume change of NMCT during the whole process of Na+ de/intercalation is only 3.2%. These data indicate that NMCT is a promising cathode material for sodium ion batteries (SIBs). [ABSTRACT FROM AUTHOR]

Here we report an environmentally friendly, one-pot strategy toward preparation of nickel nanoparticle-decorated reduced graphene-oxide (Ni-RGO) nanostructures, by employing Ni(AC) 2 as nickel source and ethylene glycol as both solvent and reducing agent via a facile microwave irradiation heating approach. The results show that Ni nanoparticles with an average diameter of around 40 nm are homogeneously anchored onto the surface of RGO sheets. As compared to the pure Ni nanoparticles and RGO sheets, Ni-RGO composites with over 64 wt% loading of Ni nanoparticles possess superior catalytic activities and selectivity toward the reduction of 4-nitrophenol. The corresponding kinetic reaction rate constant (defined as κ ) is even four-fold compared to pure Ni nanoparticles. Such promising composites show great potential for friendly treatment of industrial waste containing nitrophenol in a simple, sustainable and green way. [ABSTRACT FROM AUTHOR]

Li-O 2 battery is the leading next-generation battery system, which is known for its extremely high theoretic specific energy. However, the Li metal used in Li-O 2 batteries suffers from low Li utilization and safety hazards. In this work, as an alternative to Li anode, Li 21 Si 5 powders, which are synthesized by an easy mechanical process, are incorporated into a Li-ion oxygen battery. The electrochemical property of the prepared battery and its cycling stability are investigated. Without electrochemical prelithiation, the pursuit of Li-Si alloy anodes in this study provides an easy and scalable strategy for preparing Li-ion oxygen batteries. [ABSTRACT FROM AUTHOR]

Ordered mesoporous TiC–C (OMTC) composites were prepared and served as catalysts for nonaqueous Li–O2 batteries. The OMTC cathodes showed high specific capacity, low overpotential and good cyclability. Furthermore, the reaction mechanism of Li–O2 batteries during charge and discharge processes was investigated extensively by XRD, XPS and in situ GC-MS methods. [ABSTRACT FROM AUTHOR]

Li metal can potentially deliver much higher specific capacity than commercially used anodes. Nevertheless, because of its poor reversibility, abundant excess Li (usually more than three times) is required in Li metal batteries, leading to higher costs and decreased energy density. Here, a concentrated lithium bis(trifluoromethane sulfonyl) imide (LiTFSI)–lithium nitrate (LiNO3)–lithium bis(fluorosulfonyl)imide (LiFSI) ternary‐salts electrolyte is introduced to realize a high stable Li metal full‐cell with only a slight excess of Li. LiNO3 and LiFSI contribute to the formation of stable Li2O–LiF‐rich solid electrolyte interface layers, and LiTFSI helps to stabilize the electrolyte under high concentration. Li metal in the electrolyte remains stable over 450 cycles and the average Coulombic efficiency reaches 99.1%. Moreover, with 0.5 × excess Li metal, the Coulombic efficiency of Li metal in the LiTFSI–LiNO3–LiFSI reaches 99.4%. The electrolyte also presents high stability to the LiFePO4 cathode, the capacity retention after 500 cycles is 92.0% and the Coulombic efficiency is 99.8%. A Li metal full‐cell with only 0.44 × excess Li is also assembled, it remains stable over 70 cycles and 83% of the initial capacity is maintained after 100 cycles. A concentrated ternary‐salts electrolyte is developed for Li metal batteries. The LiNO3 and LiFSI in the electrolyte promote the formation of Li2O–LiF‐rich solid electrolyte interface layers, contributing to the high Coulombic efficiency of the Li anode. With the ternary‐salts electrolyte, the Li metal full‐cell with only 0.44 × excess Li remains stable over 70 cycles without evident capacity fading. [ABSTRACT FROM AUTHOR]

The efficient utilization of solar energy in battery systems has emerged as a crucial strategy for promoting green and sustainable development. In this study, an innovative dual‐photoelectrode vanadium–iron energy storage battery (Titanium dioxide (TiO2) or Bismuth vanadate (BiVO4) as photoanodes, polythiophene (pTTh) as photocathode, and VO2+/Fe3+ as redox couples.) is proposed, which can autonomously charge under sunlight. The dual‐photoelectrode structure enables the efficient harnessing of solar energy. All processes are spontaneous and do not require external power sources. It is noteworthy that the vanadium–iron energy storage battery demonstrates excellent stability and remarkably low cost. The results show that the combinations of TiO2‐pTTh and BiVO4‐pTTh as photoelectrodes achieve spontaneous conversion rates of 29.17% and 25.46% for VO2+ and 25.6% and 23% for Fe3+ after 4 h of light charging. This study offers a promising solution for the development of large‐scale, low‐cost solar energy storage batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Li-rich Mn-based oxides (LRMOs) are considered as one of the most-promising cathode materials for next generation Li-ion batteries (LIBs) because of their high energy density. Nevertheless, the intrinsic shortcomings, such as the low first coulomb efficiency, severe capacity/voltage fade, and poor rate performance seriously limit its commercial application in the future. In this work, we construct successfully g-C 3 N 4 coating layer to modify Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 (LMNC) via a facile solution. The g-C 3 N 4 layer can alleviate the side-reaction between electrolyte and LMNC materials, and improve electronic conduction of LMNC. In addition, the g-C 3 N 4 layer can suppress the collapse of structure and improve cyclic stability of LMNC materials. Consequently, g-C 3 N 4 (4 wt%)-coated LMNC sample shows the highest initial coulomb efficiency (78.5%), the highest capacity retention ratio (78.8%) and the slightest voltage decay (0.48 V) after 300 loops. Besides, it also can provide high reversible capacity of about 300 and 93 mAh g−1 at 0.1 and 10C, respectively. This work proposes a novel approach to achieve next-generation high-energy density cathode materials, and g-C 3 N 4 (4 wt%)-coated LMNC shows an enormous potential as the cathode materials for next generation LIBs with excellent performance. [ABSTRACT FROM AUTHOR]

Safe rechargeable batteries of improved energy density and high power performance are urgently needed for the development of large electric devices. Herein, an Li‐based organic liquid anode is proposed, and an organic oxygen battery with a metal organic framework membrane separator is realized, which is able to conduct Li ions and separate other large species in the system. Equipped with the dual redox mediator strategy, the organic oxygen battery exhibits superior rate performance with long cycling life and low overpotential. A "solid electrolyte interface"‐like layer is observed between the organic liquid anode and the ion conducting separator. This work not only introduces a new type of anode for Li‐based batteries, but also provides fundamental insights for the better application of biphenyl‐based liquid anodes. [ABSTRACT FROM AUTHOR]

We confirmed the existence of LiO 2 by electrochemical quartz crystal microbalance (EQCM) in TEGDME based Li-O 2 batteries. Our results indicated that Li 2 O 2 is generated through stepwise electrochemical reactions rather than disproportionation. We report for the first time that the formed Li 2 O 2 oxidizes to LiO 2 at relative negative potential and O 2 at positive potential respectively. Our conclusions were based on both experimental observations and quantitative analysis. This may enlighten us to reconsider the Li-O 2 batteries mechanisms in a quantitative way. [ABSTRACT FROM AUTHOR]

A polyaniline/graphene composite with covalently-bond is synthesized by a novel approach. In this way, graphene oxide is functionalized firstly by introducing amine groups onto the surface with the reduction of graphene oxide in the process and then served as the anchor sites for the growth of polyaniline (PANI) via in-situ polymerization. The composite material is characterized by electron microscopy, the resonant Raman spectra, X-ray diffraction, transform infrared spectroscopy and X-ray photoelectron spectroscopy. The electrochemical properties of the composite are measured by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charging/discharging. With the functionalization process, the graphene/polyaniline composite electrode exhibits remarkably enhanced electrochemical performance with specific capacitance of 489 F g −1 at 0.5 A g −1 , which is superior to those of its individual components. The outstanding electrochemical performance of the hybrid can be attributed to its covalently synergistic effect between graphene and polyaniline, suggesting promising potentials for supercapacitors. [ABSTRACT FROM AUTHOR]

Background: To study the incidence and risk factors of shivering in pregnant women during cesarean section. Methods: We performed a prospective nested case-control study involving parturients scheduled for cesarean sections between July 2018 and May 2021. The overall incidence of intraoperative shivering and its potential risk factors were investigated. The potential risk factors evaluated were pain, anxiety, emergency surgery, transfer from the delivery room, epidural labor analgesia, membrane rupture, labor, and the timing of the surgery. Shivering and body temperature at different time points during the cesarean section were also recorded. The selected seven time points were: entering the operating room, post-anesthesia, post-disinfection, post-delivery, post-oxytocin, post additional hysterotonics, and before leaving the operating room. Results: We analyzed 212 cesarean section parturients. The overall incidence of shivering was 89 (42.0%). Multivariate logistic regression showed that anxiety, emergency delivery, and transfer from the delivery room to the operating room increased the overall shivering incidence (odds ratio = 1.77, 2.90, and 3.83, respectively). The peak shivering incidence occurred after skin disinfection (63, 29.7%), and the lowest body temperature occurred after oxytocin treatment (36.24 ± 0.30 °C). Stratified analysis of surgery origin showed that emergency delivery was a risk factor for shivering (odds ratio = 2.99) in women transferred from the obstetric ward to the operating room. Conclusion: Shivering occurred frequently during cesarean sections, with the peak incidence occurring after skin disinfection. Anxiety, emergency delivery, and transfer from the delivery room to the operating room increased the risk of shivering development during cesarean sections. Trial registration: The study protocol was registered online at China Clinical Registration Center (registration number: ChiCTR-ROC-17010532, Registered on 29 January 2017). [ABSTRACT FROM AUTHOR]

The NASICON structure of Na 3 V 2 (PO 4) 2 F 3 (NVPF) separates the valence electrons between the polyanion group and V and regulates the redox coupling energy. As a result, NVPF exhibits a high operating voltage in sodium-ion batteries. However, NVPF cathode material has poor specific capacity and low-rate performance. It is necessary to improve the electrochemical performance by increasing the electronic conductivity and accelerating the ion diffusion rate. Through morphology control, more active sites and ion channels can be provided to enhance rate performance and cycle stability. However, there are few reviews on how to control the morphology of NVPF. Therefore, this paper starts with the factors affecting the morphology of NVPF. The effects of pH value, surfactant, and external additives on its morphology were systematically summarized. On this basis, reasonable strategies, including morphology design, preparation method, structure control, surface modification, and defect engineering, are summarized. This paper provides theoretical support for the development of high-voltage NVPF. It provides inspiration for creating NVPF cathode materials with high specific capacity and high cycle performance. • The effects of various factors on the morphology of Na 3 V 2 (PO 4) 2 F 3 were systematically summarized. • The electrochemical properties of Na 3 V 2 (PO 4) 2 F 3 coated with different carbon sources were summarized. • The low-pressure platform caused by fluorine loss and its fluorine supplement measures are explained. • The effects of binders and electrolyte additives on Na 3 V 2 (PO 4) 2 F 3. [ABSTRACT FROM AUTHOR]

The aim of this paper is to evaluate the efficacy and safety of three different norepinephrine dosing regimens for preventing spinal hypotension in cesarean section. In this randomized double-blinded controlled study, 120 parturients scheduled for elective section delivery under spinal anesthesia were assigned to 1 of 4 groups. In the control group, patients received saline infusion. In three norepinephrine groups, the infusion dosage regimens were 5, 10, and 15 μg/kg/h, respectively. Hypotension was treated with a rescue bolus of 10 μg norepinephrine. The study protocol was continued until the end of surgery. The primary outcome was the proportion of participants that underwent hypotension. The proportion of hypotension participants was significantly reduced in the norepinephrine groups (37.9%, 20%, and 25%, respectively) compared to that in the control group (86.7%). However, the highest dose of norepinephrine (15 μg/kg/h) resulted in more hypertension episodes. In addition, blood pressure was better maintained in the norepinephrine 5 μg/kg/h and 10 μg/kg/h groups than in the control group and 15 μg/kg/h group. No significant differences in other hemodynamic variables, adverse effects, maternal and neonatal blood gases, or Apgar scores were observed among the groups. In summary, for patients who undergo cesarean delivery under spinal anesthesia, infusion of 5–10 μg/kg/h norepinephrine was effective to reduce hypotension incidence without significant adverse effects on maternal and neonatal outcomes. Clinical Trial Registration Number is ChiCTR-INR-16009452. [ABSTRACT FROM AUTHOR]

A practicable strategy has been developed to build a LixSi–O2 battery using an in situ formed Li–Si alloy anode based on the decomposition of Li3N pre-loaded in the cathode. The LixSi–O2 battery has achieved more than 100 stable charge–discharge cycles with lower polarization than that using a lithium metal anode. [ABSTRACT FROM AUTHOR]