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The modern lithium-ion battery (LIB) configuration was enabled by the “magic chemistry” between ethylene carbonate (EC) and graphitic carbon anode. Despite the constant changes of cathode chemistries with improved energy densities, EC-graphite combination remained static during the last three decades. While the interphase generated by EC protects the fragile graphitic structure, the intrinsic disadvantages of EC (high viscosity, high melting point, excessive interphase growth) lead to mediocre power density and poor performances of LIB at sub-zero temperatures, where lithium depositions form upon charging. Such performance compromises arise from the fundamental dilemma between requiring effective interphase protection and high impedance from excessive growth of interphase. In this work, we designed and synthesized a “double EC” molecule as electrolyte additive to resolve the above dilemma. Erythritol bis(carbonate) (EBC) possesses lower LUMO energy level than EC and hence tends to decompose prior to EC reduction, but its weak solvation toward Li+ restricts the extent of its reduction, thus minimizing the interphase thickness and the corresponding impedances. Electrolytes containing EBC enables both the charging and discharging of ampere-size LIB pouch cells at sub-zero temperatures from 0 to -20℃, demonstrating that the key approach to improve low temperature performances lies in how to tailor interphasial chemistry rather than the bulk electrolyte composition.

Sulfurized polyacrylonitrile (SPAN) is a promising high-capacity cathode material. In this work, we use spatially resolved X-ray absorption spectroscopy combined with X-ray fluorescence (XRF) microscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy to examine the structural transformation of SPAN and the critical role of a robust cathode-electrolyte interface (CEI) on the electrode. LiSx species forms during the cycling of SPAN. However, in carbonate-based electrolytes and ether-based electrolytes with LiNO3 additives, these species are well protected by the CEI and do not dissolve into the electrolytes. In contrast, in an ether-based electrolyte without the LiNO3 additive, LiSx species dissolve into the electrolyte, resulting in the shuttle effect and capacity loss. Examination of the Li anode by XRF and SEM reveals dense spherical Li morphology in ether-based electrolytes, but sulfur is present in the absence of the LiNO3 additive. In contrast, porous dendritic Li is found in the carbonate electrolyte. These analyses established that an ether-based electrolyte with LiNO3 is a superior choice that enables stable cycling of both electrodes. Based on these insights, we successfully demonstrate the stable cycling of high areal loading SPAN cathode (>6.5 mA h cm-2) with lean electrolyte amounts, showing promising Li∥SPAN cell performance under practical conditions.

Summary van der Waals layered metal chalcogenide Bi2Te3 has shown exceptional capacity and rate capability in alkali-ion batteries but the underlying reaction mechanism with Li+, Na+, and K+ remains undiscovered. It is unexpected that Na+ electrochemistry outperforms Li+ and K+ at high current densities. Here, in situ transmission electron microscopy is used to uncover nanoscale transformations during lithiation, sodiation, and potassiation, which follows two-step conversion and alloying reactions with Li+ and Na+, and three-step intercalation-conversion-alloying reactions with K+. Counterintuitively, sodiation exhibits the highest reaction kinetics, and its origin can be elucidated by first-principles and finite-element simulations in two aspects. The lower interfacial strain accommodation energy between Bi2Te3 and its Na-conversion products allows more facile sodiation phase transformation than Li- and K-ion reactions. The higher electrochemo-mechanical stress concentration at the concave-shaped sodiation reaction front facilitates continued Na-ion diffusion and reaction propagation. These fundamental insights are essential for fast-charging alkali-ion batteries.

Manganese-rich layered oxide materials hold great potential as low-cost and high-capacity cathodes for Na-ion batteries. However, they usually form a P2 phase and suffer from fast capacity fade. In this work, an O3 phase sodium cathode has been developed out of a Li and Mn-rich layered material by leveraging the creation of transition metal (TM) and oxygen vacancies and the electrochemical exchange of Na and Li. The Mn-rich layered cathode material remains primarily O3 phase during sodiation/desodiation and can have a full sodiation capacity of ca. 220 mAh g-1 . It delivers ca. 160 mAh g-1 specific capacity between 2-3.8 V with >86 % retention over 250 cycles. The TM and oxygen vacancies pre-formed in the sodiated material enables a reversible migration of TMs from the TM layer to the tetrahedral sites in the Na layer upon de-sodiation and sodiation. The migration creates metastable states, leading to increased kinetic barrier that prohibits a complete O3-P3 phase transition.

Lithium sulfur batteries (LSBs) are promising next-generation rechargeable batteries due to the high gravimetric energy, low cost, abundance, nontoxicity, and high sustainability of sulfur. However, the dissolution of high-order polysulfide in electrolytes and low Coulombic efficiency of Li anode require excess electrolytes and Li metal, which significantly reduce the energy density of LSBs. Quasi-solid-state LSBs, where sulfur is encapsulated in the micropores of carbon matrix and sealed by solid electrolyte interphase, can operate under lean electrolyte conditions, but a low sulfur loading in carbon matrix (

The lithium–sulfur (Li–S) battery is a promising next-generation energy storage technology because of its high theoretical energy and low cost. Extensive research efforts have been made on new materials and advanced characterization techniques for mechanistic studies. However, it is uncertain how discoveries made on the material level apply to realistic batteries due to limited analysis and characterization of real high-energy cells, such as pouch cells. Evaluation of pouch cells (>1 A h) (instead of coin cells) that are scalable to practical cells provides a critical understanding of current limitations which enables the proposal of strategies and solutions for further performance improvement. Herein, we design and fabricate pouch cells over 300 W h kg−1, compare the cell parameters required for high-energy pouch cells, and investigate the reaction processes and their correlation to cell cycling behavior and failure mechanisms. Spatially resolved characterization techniques and fluid-flow simulation reveal the impacts of the liquid electrolyte diffusion within the pouch cells. We found that catastrophic failure of high-energy Li–S pouch cells results from uneven sulfur/polysulfide reactions and electrolyte depletion for the first tens of cycles, rather than sulfur dissolution as commonly reported in the literature. The uneven reaction stems from limited electrolyte diffusion through the porous channels into the central part of thick cathodes during cycling, which is amplified both across the sulfur electrodes and within the same electrode plane. A combination of strategies is suggested to increase sulfur utilization, improve nanoarchitectures for electrolyte diffusion and reduce consumption of the electrolytes and additives.

Despite being an advanced battery thermal management (BTM) strategy, the phase change material (PCM) cooling technology still suffers from the low thermal stability of the PCMs in practical applications, which leads to the leakage of the phase change ingredient, shape change or even collapse concerns under high temperature. Here we propose a creative idea for constructing a cross-linked polymeric structure with aliphatic side chains, namely, polymer PCM (PoPCM), through a facile one-step free-radical polymerization of octadecyl acrylate and crosslinkers. The aliphatic chains “tied up” on the cross-linked polymeric skeleton via “chemical bonding” and provided a high latent heat of 98.8 J g−1 without leakage, and therefore, delivered a stable solid–solid phase change behavior during long-term operation. The thermosetting 3-dimensional cross-linked structure simultaneously endowed the PoPCM with the anti-volume-expansion capability and excellent heat tolerance up to 250 °C without any deformation or leakage. When applied for BTM, the solid–solid PoPCM module demonstrated excellent and stable heat dissipation performance. The maximum temperature was 45.3 °C, and the temperature difference of the battery module could be controlled below 3.1 °C during the cyclic charge–discharge tests. Combining with the industrially available reagents and the simple preparation procedure at the kilogram level, we believe that this new strategy can present PCMs with superior feasibility for practical application in BTM.

Sustainable water-splitting hydrogen production has long been considered one of the most promising energy conversion technologies, but enormous challenges remain: for instance, water electrolysis suffers from high overpotential and over energy consumption under neutral pH conditions. Here, taking advantage of the memory effect of layered double hydroxide (LDH), we report an energy-efficient neutral water electrolyzer material based on LDH with multiple vacancy defects. Benefiting from the improved electrical conductivity, larger electrochemical surface area (ECSA), and faster charge transfer, the NiFe LDH with O, Ni, and Fe vacancies exhibits a low overpotential of 87 mV at 10 mA/cm2 for hydrogen evolution reaction (HER) in a pH 7 buffer electrolyte. Impressively, the as-fabricated vacancy-containing NiFe LDH (v-NiFe LDH) splits water with a current density of 10 mA/cm2 at ∼1.60 V in a two-electrode device, outperforming most other water-splitting catalysts in neutral media. Such an electrolyzer setup cou...

Polyimide (PI) membranes with superior chemical resistance, insulation and self-extinguishing are attracting numerous attentions as the separators of lithium-ion batteries (LIBs), but significant challenges of low mechanical strength and poor electrolyte affinity still remain. Herein, a new kind of environmentally friendly hydrogen-bond (H-bond) cross-linked cellulose/carboxylated PI (Cellulose/PI-COOH) nanofiber composite separator is prepared via electrospinning followed by imidization and alkaline hydrolysis. Besides inheriting the high porosity of the pristine PI separator to absorb the electrolyte, the three-dimensional interconnected structure resulting from H-bond cross-linking is beneficial to improving the mechanical properties of the composite separator, and thereby delivers a tensile strength of 34.2 MPa, 5 times higher than that of the pristine PI separator (6.8 MPa). Meanwhile, the exposed hydroxyl groups on the cellulose, and carboxyl and imino groups on the carboxylated PI can also enhance the electrolyte affinity and wettability of the Cellulose/PI-COOH separator, which plays an important role in increasing the ionic conductivity (0.51 mS cm−1) and widening the electrochemical stability window (∼5.1 V). Consequently, compared with the polypropylene separator and PI separator, the H-bond cross-linked Cellulose/PI-COOH separators show better cycle performance and rate performance when adopted in lithium iron phosphate (LiFePO4) and lithium cobaltate (LiCoO2) half-cells. For example, the Cellulose/PI-COOH-based LiFePO4 half-cell demonstrates the highest initial discharge capacity of 166.2 mAh g-1 and capacity retention rate of 90%, much higher than the pristine PI-based LiFePO4 half-cell (114.6 mAh g-1, 86%). Furthermore, the much enhanced tensile strength, flexibility, thermal stability and flame-resistance of the Cellulose/PI-COOH separator are believed to greatly enhance the safety performance of the obtained LIBs.

Majority existing organic composite phase change materials (CPCMs) are flammable that result in thermal hazards such as fire and explosions in battery modules. Furthermore, the performance of PCM-based battery modules in extreme conditions like thermal runaway has not been studied adequately. In this study, a tubular CPCM-cell structure is designed using physically flame-retardant-modified CPCMs, and a series of experiments on the CPCMs with/without real cells is conducted with calorimeter tests and SEM analysis on morphology structure. First, the calorimeter tests and comparison on the heat release rate (HRR) are conducted on the CPCMs with and without flame retardant additives. Results show that the addition of Al(OH)3 reduced the HRR from 242.5 to 204.4 kW/m2 with 15 wt% additives. Besides, the analysis of the mitigating performances of structure-enhanced tubular module and traditional cuboid module with real batteries is conducted. A factor of safety (FOS) parameter is defined to evaluate the safety degree of thermal runaway domino with energy density. The FOS of blank, CPCM–0C, and CPCM–15C modules are 0, 3.59, and 16.67, respectively, while that of CPCM-15T reaches 21.01, indicating a significant improvement on mitigating effects by structure enhancement compared to adding flame retardant additives. This study brings novelty in the design of PCM-based battery modules, particularly from the thermal safety prospect.

To enhance the photocatalytic recycling capability of the TiO2-based photocatalysts, a new kind of plate-like In2O3/TiO2 nanotube array (TNA) hybrids is fabricated herein by constructing TNAs via an anodization method followed by doping In2O3 via a solvothermal method. The obtained In2O3/TNA hybrid demonstrates a well-aligned nanotubular structure with homogeneous dispersion of In2O3 nanoparticles. It shows a much higher degradation rate of 77% after 2 h compared to TNA (37%). In addition, the plate-like feature endows the photocatalysts with an excellent recycling capability. These superior photocatalytic degradation performances can be ascribed to the following factors: (1) the enhanced light absorption ability and efficient separation of photoexcited electron-hole pairs derived from the formation of the heterostructure between the interface of TiO2 and In2O3; (2) the efficient transport of reactant molecules provided by the well-defined TNAs and the homogeneous distribution of the In2O3 nanoparticles without blocking the nanotubes.

Fibroblast growth factor receptor 2 (FGFR2) was demonstrated to correlate to the progression and prognosis of intrahepatic cholangiocarcinoma (ICC) by numerous evidences. However, as a well‐recognized suppressor of FGFR2 signalling, the clinical significance of Sprouty (SPRY) family of ICC has not been investigated. In our study, the expressions of SPRY1‐4 in 20 pairs of fresh tumour tissues were detected with qPCR, and in 108 cases of paraffin‐embedded tissues with immunohistochemistry. The prognostic value of SPRY family in ICC was estimated with univariate analysis and multivariate analysis. As a result, SPRY2 was identified as an independent prognostic biomarker predicting favourable prognosis of ICC. High SPRY2 expression was correlated with good differentiation of ICC. With silencing SPRY2 expression, we demonstrated that SPRY2 could suppress FGFR2‐induced ERK phosphorylation, migration, invasion and epithelial‐mesenchymal transition (EMT) under FGF1 stimulation. By overexpressing SPRY2‐wide type or SPRY2‐Y55F, the tyrosine‐55 of SPRY2 was demonstrated to be essential in suppressing ERK phosphorylation, tumour invasion and EMT of ICC cells. In conclusion, SPRY2 was correlated with favourable prognosis of ICC via suppressing FGFR2‐induced ERK phosphorylation, invasion and EMT. The phosphorylation of SPRY2‐Y55 was required in this tumour‐suppressing function of SPRY2.

High performance liquid chromatography (HPLC) can be used to systematically and rapidly screen the potential additives for the inhibition of the polysulfide shuttle effect in a Li-S battery. The method is proven effective by investigating the 18 compounds which were reported in the literature as redox shuttle inhibitors for Li-S batteries. The change of the polysulfide ions from being exposed to 18 different redox shuttle inhibition additives was qualitatively and quantitatively determined. The changes of polysulfide species and elemental sulfur were successfully used to study the inhibition effect of the additives in Li-S batteries. It was confirmed that nitrate salts under the same concentration showed the best inhibition effect for the polysulfide shuttle reaction. However even in the electrolyte with nitrate additives, the shuttle reactions between Li metal and polysulfides (and elemental sulfur) are still notable, and thus the search for a better polysulfide shuttle inhibitor is ongoing and critical for improving the electrochemical performance of Li-S batteries.

Graphene/Fe3O4 hybrids have long been regarded as promising anode materials for lithium-ion batteries but remain significant bottlenecks of inhomogeneous/large Fe3O4 particle size and agglomeration during the repeated lithiation/dethiation process. By carefully selecting a metallo-organic molecule of ferrocene as the building block, a novel methodology has been explored herein for the preparation of sandwich-type graphene@Fe3O4 dots/amorphous carbon (G@Fe3O4/C) hybrids via a Friedel–Crafts crosslinking-induced spontaneous growth process. As prepared, ultra-small Fe3O4 dots of 2–3 nm are distributed uniformly in the amorphous carbon matrix coated on the surface of graphene. The ultralow size of Fe3O4 dots is able to minimize the volume change and Li+ migrating distance, while the carbon matrix and graphene framework prevent Fe3O4 dots from aggregation and offer a superior conductive skeleton along with a flexible framework to buffer the volume changes. In addition, the well-developed pore structure can accommodate the large volume change and facilitate the electrolyte diffusion/transfer, thereby increasing the ion accessible surface area, especially at high charge–discharge rates. Consequently, G@Fe3O4/C presents excellent lithium storage performances, including a highly reversible capacity of 1241 mAh g−1, an outstanding cycling stability after 200 cycles (1055 mAh g−1) and a superior high-rate capability (724 mAh g−1 at 5 A g−1).

Anionic redox reaction (ARR) in lithium- and sodium-ion batteries is under hot discussion, mainly regarding how oxygen anion participates and to what extent oxygen can be reversibly oxidized and reduced. Here, a P3-type Na0.6[Li0.2Mn0.8]O2 with reversible capacity from pure ARR was studied. The interlayer O-O distance (peroxo-like O-O dimer, 2.506(3) Å), associated with oxidization of oxygen anions, was directly detected by using a neutron total scattering technique. Different from Li2RuO3 or Li2IrO3 with strong metal-oxygen (M-O) bonding, for P3-type Na0.6[Li0.2Mn0.8]O2 with relatively weak Mn-O covalent bonding, crystal structure factors might play an even more important role in stabilizing the oxidized species, as both Li and Mn ions are immobile in the structure and thus may inhibit the irreversible transformation of the oxidized species to O2 gas. Utilization of anionic redox reaction (ARR) on oxygen has been considered as an effective way to promote the charge-discharge capacity of the layered oxide cathodes for lithium- or sodium-ion batteries. The detailed mechanism of ARR, in particular how crystal structure affects and coordinates with the ARR, is not yet well understood. In the present work, a combination of X-ray and neutron total scattering measurements has been performed to study the structure of the prototype P3-type layered Na0.6[Li0.2Mn0.8]O2 with pure ARR. Unique structural characteristics, rather than prevailing knowledge of covalency of metal-oxygen, enable the stabilization of the crystal structure of Na0.6[Li0.2Mn0.8]O2 along with the ARR. This work suggests that reversible ARR can be manipulated by proper structure designs, thus to achieve high lithium or sodium storage in layered oxide cathodes. For P3-type Na0.6[Li0.2Mn0.8]O2 with relatively weak Mn-O covalent bonding, crystal structure factors play an important role in stabilizing the oxidized species, inhibiting the irreversible transformation of the oxidized species to O2 gas. The finding is important for better design of layered oxide positive materials with higher reversible capacity via the introduction of a reversible anionic redox reaction.

Utilizing the anionic redox reaction opens new approaches for the development of new cathode materials with extra capacities. Although, it suffers from several obstacles such as voltage hysteresis and sluggish kinetics. In this paper, a new layered chalcogenide-based on dual anionic-redox reaction is reported. The newly designed layered NaCrSSe exhibits the capacity of almost all Na + intercalation/deintercalation (137 mAh g−1 at 50 mA g−1), and a unique charge/discharge feature with a small polarization of 0.15 V and high energy efficiencies of ~92% in initial cycles. Furthermore, a superior high-rate charge capacity of 115.5mAh g−1 (83.7% retention) was achieved at 27.8 C (4000 mA g−1). Systematic characterization studies on structure evolution and DFT calculation show the charge compensation of S and Se anions during cycling. These results will enrich the anion redox chemistry and provide valuable information for developing new anion-redox based cathode materials with high capacity and fast kinetics.

An investigation of novel electrolyte formulations to improve low temperature performance of Li/graphite half cells has been conducted. A novel electrolyte co-solvent, isoxazole (IZ), has been investigated in electrolyte systems composed of lithium difluoro(oxalato)borate (LiDFOB) in fluoroethylene carbonate (FEC) and LiDFOB in ethylene carbonate (EC). Cells containing 1 M LiDFOB FEC: IZ electrolyte have a significant improvement in capacity retention and reversible capacity at −10 °C. Ex-situ surface analysis of the cycled electrodes suggests that reduction of LiDFOB results in an oxalate rich solid electrolyte interphase (SEI). Addition of FEC, results in improved stability of the anode SEI preventing further decomposition of isoxazole solvent and improving cycling performance.

Mitochondrial DNA is generally regarded to evolve faster than nuclear DNA in animals, whereas if this is also true in fungi remains unclear. Herein, we annotate the first complete mitochondrial genome (mitogenome) of the cyclosporin-producing fungus Tolypocladium inflatum and report the genome-wide sequence variations among five isolates originating from distantly separated localities. We found that T. inflatum has among the most compact of fungal mitogenomes; its 25 kb DNA molecule encodes all standard fungal mitochondrial genes and harbors only one intron. Transcriptional analyses validated the expression of most conserved genes. We found several uncommon repetitive elements and evidence of gene transfer from the mitochondrion to the nucleus. Phylogenetic analyses confirmed the placement of T. inflatum in the fungal order Hypocreales although there was uncertainty on its family-level affiliation. Comparative genomic analyses among the five isolates identified an overall lower level of intraspecific variation in mitogenomes than in nuclear genomes; however, both the nuclear and mitochondrial genomes revealed similar isolate relationships, not correlating with geographic sources of these isolates. Our study shed new insights into the evolution of the medicinally important ascomycete T. inflatum.

Chromium-based layered cathode materials suffer from the irreversible disproportionation reaction of Cr4+ to Cr3+ and Cr6+, which hinders the reversible multi-electron redox of Cr ions in layered cathodes, and limits their capacity and reversibility. To address this problem, a novel O3-type layer-structured transition metal oxide of NaCr1/3Fe1/3Mn1/3O2 (NCFM) was designed and studied as a cathode material. A high reversible capacity of 186 mA h g−1 was achieved at a current rate of 0.05C in a voltage range of 1.5 to 4.2 V. X-ray diffraction revealed an O3 → (O3 + P3) → (P3 + O3′′) → O3′′ phase-transition pathway for NCFM during charge. X-ray absorption, X-ray photoelectron and electron energy-loss spectroscopy measurements revealed the electronic structure changes of NCFM during Na+ deintercalation/intercalation processes. It is confirmed that the disproportionation reaction of Cr4+ to Cr3+ and Cr6+ can be effectively suppressed by Fe3+ and Mn4+ substitution. These results demonstrated that the reversible multi-electron oxidation/reduction of Cr ions can be achieved in NCFM during charge and discharge accompanied by CrO6 octahedral distortion and recovery.

For designing porous carbon-based electrodes in electric double-layer capacitors (EDLCs), it is crucial to construct a large ion-accessible surface area as well as efficient mass transfer pathways, especially for organic electrolytes with large ion sizes. Here we report the supercapacitive properties of wormhole-like mesoporous carbon (WMC) in both 6 M KOH and 1 M tetraethylammonium tetrafluoroborate (TEABF4) electrolyte. The suitable mesopore size (3.1 nm) of WMC, which is 3 times larger than the solvated ion size of TEABF4, offers a large ion-accessible surface area for charge accumulation. The 3D continuous carbon framework and interconnected mesopore-dominant structure endow the WMC with excellent electron/electrolyte transfer pathways. As a consequence, it presents a small decrease of specific mass capacitance in TEABF4 as compared to that in KOH (174 vs. 189 F g−1, respectively), and a far superior high-rate capability in TEABF4 than most of other porous carbon materials.

The mechanism of the sulfur cathode in Li–S batteries has been proposed. It was revealed by the real-time quantitative determination of polysulfide species and elemental sulfur by means of high-performance liquid chromatography in the course of the discharge and recharge of a Li–S battery. A three-step reduction mechanism including two chemical equilibrium reactions was proposed for the sulfur cathode discharge. The typical two-plateau discharge curve for the sulfur cathode can be explained. A two-step oxidation mechanism for Li2S and Li2S2 with a single chemical equilibrium among soluble polysulfide ions was proposed. The chemical equilibrium among S52–, S62–, S72–, and S82– throughout the entire oxidation process resulted for a single flat recharge curve in Li–S batteries.

BiOBr/BiVO4 heterojunction photocatalysts were synthesised via facile hydrothermal methods and mixed by ultrasonic treatment. The as-prepared samples were characterised by X-ray diffraction, Fourier transform infrared spectra, scanning electron microscopy, transmission electron microscopy and UV–vis diffuse reflection spectrometry. The photocatalytic activity of the samples was evaluated by degradation of Rhodamine B (RhB) under visible light irradiation (400 nm

ObjectiveTo investigate the mechanism through which tacrolimus, often used to treat refractory nephropathy, protects against puromycin-induced podocyte injury.MethodsAn in vitro model of puromycin-induced podocyte injury was established by dividing podocytes into three groups: controls, puromycin only (PAN group), and puromycin plus tacrolimus (FK506 group). Podocyte morphology, number, apoptosis rate and microtubule associated protein 1 light chain 3 alpha ( LC3) expression were compared.ResultsPuromycin caused podocyte cell body shrinkage and loose intercellular connections, but podocyte morphology in the FK506 group was similar to controls. The apoptosis rate was lower in the FK506 group versus PAN group. The low level of LC3 mRNA observed in untreated podocytes was decreased by puromycin treatment; however, levels of LC3 mRNA were higher in the FK506 group versus PAN group. Although LC3-I and LC3-II protein levels were decreased by puromycin, levels in the FK506 group were higher than the PAN group. Fewer podocyte autophagosomes were observed in the control and FK506 groups versus the PAN group. Cytoplasmic LC3-related fluorescence intensity was stronger in control and FK506 podocytes versus the PAN group.ConclusionsTacrolimus inhibited puromycin-induced mouse podocyte damage by regulating LC3 expression and enhancing autophagy.

Considering the usage of smart phones, electrical vehicles, and power sources for grid storage application, lithium ion battery (LIB) operating under harsh circumstances have become a serious issue due to the sluggish ionic conductivity and increased viscosity of electrolyte at low temperatures. Ethylene carbonate (EC) is a widely used electrolyte component of commercial LIB owing to the suitable electrochemical stability window, high dielectric constant, and especially, its ability to form stable solid electrolyte interphase (SEI) on the graphite anode, which prevents continuous electrolyte decomposition and resulted in excellent cycling stability on graphite anode. However, its high freezing point (36℃), greatly increases electrolyte solidification temperature and hurts ionic conductivity at low temperatures, thereby leading to a narrow operation temperature range for LIB using EC-based electrolytes. Recently, plenty of efforts have been made to extend LIB operating temperature range, using techniques such as self-heating method with extra Ni-foil in specially designed cell configuration1, or electrolyte modifications by introducing low melting point solvents to increase ionic conductivity at low temperatures. Electrolyte modification is the most effective approach due to its low cost, high flexibility, and convenience. It can easily alter electrolyte physical and chemical properties, affect SEI chemical compositions, and result in positive impact on battery performance. Particularly, SEI is the interphase between anode and electrolyte, which allows Li ion transportation and insulates electron transfer, protects anode surface and prevents electrolyte decomposition. Many different research groups have made a lot of progress of electrolyte modification, including adjusting solvent salt combinations, fluorinating of solvents, and developing novel additives.2 Nevertheless, there are still many challenges need to be addressed for stable low temperature operation. Herein, considering the research importance and current progress of low temperature electrolyte, we screened several organic compounds as co-solvents or additives to improve low temperature performance while keeping other properties of current LIB. For example, propylene carbonate (PC) has comparable dielectric constant and electrochemical window as EC, and much lower freezing point (-49℃), making it very promising candidate for low temperature electrolyte.3 Unfortunately, PC cannot be used as single solvent for LIBs because it usually co-intercalates into graphite layer and cause graphite exfoliation. In order to prevent co-intercalation of PC, a stable SEI needs to be formed. We developed several new electrolytes using different salts, solvents and additives, which have higher reduction potential than PC intercalation voltage and enable stable SEI formation, making PC-based low temperature electrolyte application possible. In addition, advanced characterization techniques were used to characterize the interphase properties to reveal underlying mechanism of improved electrochemical performances by modifying electrolyte composition. These results will be presented at meeting. Reference C.-Y. Wang, Nature, 2016, 529, 515. G. Zhu, Journal of Power Sources, 2015, 300, 29-40. Q. Li, Applied Materials & Interfaces, 2017, 9, 42761-42768. Acknowledgement The work carried out at Brookhaven National Laboratory was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Vehicle Technology Office of the US Department of Energy through the Applied Battery Research for Transportation (ABRT) program.

Poly (ethylene oxide) (PEO) polymer electrolytes are promising candidates for next-generation rechargeable lithium batteries. However, the poor interfacial stability between 4 V cathodes and PEO electrolytes impedes their applications in 4 V lithium batteries with high energy density. Here, we demonstrate a facile and effective strategy to enhance the interfacial stability by the synergy of Li1.5Al0.5Ge1.5(PO4)3 (LAGP) coating on the cathode surface, and salt combination in the electrolyte, even with a cut-off voltage of 4.25–4.4 V vs. Li+/Li. Nano-LAGP coated Li|PEO|LiCoO2 cell delivers stable cycling with a capacity retention of 81.9%/400 cycles and 84.7%/200 cycles at 60 °C when charged to 4.25 and 4.3 V in pure polyether electrolyte, respectively. Steady cycling is also demonstrated at room temperature and with LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode. This work offers a viable and scalable approach to improve the stability between PEO electrolytes and 4 V cathodes and open up new possibilities for practical application of 4 V lithium metal batteries.

The demand for high energy Na-ion batteries has promoted intensive research on high energy oxygen redox chemistry in layered transition metal oxide cathodes. However, most layered cathodes with oxygen redox might suffer from irreversible electrochemical reaction, fast capacity decay and underlying O2 release. Herein, we report that copper element with a strong electronegativaty can stablize Na-deficient P2-Na2/3Mn0.72Cu0.22Mg0.06O2 phase to achieve both cationic and anionic redox chemistry. Hard and soft X-ray absorption spectra demonstrate that all Mn3+/Mn4+, Cu2+/Cu3+ and O2−/(O2)n− participate in the redox reaction upon Na+ ions extraction and insertion. Density functional theory (DFT) calculations confirm that the strong covalency between copper and oxygen ensures the cationic and anionic redox activity in P2-Na2/3Mn0.72Cu0.22Mg0.06O2 phase. The P2-Na2/3Mn0.72Cu0.22Mg0.06O2 cathode could deliver stable cycling life with 87.9% capacity retention at 1C during 100 cycles, as well as high rate performance (70.3 mA h g−1 cycled at 10C). Our findings not only provide a promising guidelines to enhance the electrochemical performance of layered oxides based on anionic redox activity, but also explore the potential science behind oxygen redox process.

The endocapillary proliferative (EP) lesion is not included in the International Study of Kidney Disease in Children (ISKDC) pathological classification of Henoch-Schonlein purpura nephritis (HSPN). The main objective of the study was to determine the pathological importance of EP in the development of proteinuria in children with Henoch-Schonlein purpura nephritis (HSPN). The pathological features of 148 HSPN children with nephrotic-range proteinuria were investigated retrospectively. Urinary IgG, transferrin, and albumin levels were measured by immunonephelometry. The correlations between EP lesion and 24-h proteinuria, urinary IgG, urinary transferrin, and urinary albumin were analyzed. Renal biopsy specimens were immunohistochemically stained for nephrin and podocalyxin. Of the total 581 cases of children with HSPN who underwent renal biopsy, 148 cases (25.5%) presented with nephrotic-range proteinuria. The pathological types of HSPN with nephrotic-range proteinuria were categorized as IIb, IIIa, IIIb, IIIb with diffuse EP, IVb, pure focal EP type, and pure diffuse EP type. Among these types, pure diffuse EP type accounted for 7.4%. The levels of 24-h proteinuria and urinary albumin were the highest in pure diffuse EP type among all pathological types, and the percentage of EP correlated with 24-h proteinuria and urinary albumin levels. 24-h proteinuria was significantly higher in pure diffuse EP type relative to HSPN IIb type, and significantly higher in IIIb with EP, compared with HSPN IIIb. Nephrin, but not podocalyxin, was downregulated in EP segment. EP is an independent pathogenic factor in HSPN with nephrotic-range proteinuria. Downregulation of nephrin in EP segment is a potential molecular mechanism of nephrotic-range proteinuria. Albumin is the major urinary protein component in HSPN with EP.

Iron fluoride, an intercalation-conversion cathode for lithium ion batteries, promises a high theoretical energy density of 1922 Wh kg–1. However, poor electrochemical reversibility due to repeated breaking/reformation of metal fluoride bonds poses a grand challenge for its practical application. Here we report that both a high reversibility over 1000 cycles and a high capacity of 420 mAh g−1 can be realized by concerted doping of cobalt and oxygen into iron fluoride. In the doped nanorods, an energy density of ~1000 Wh kg−1 with a decay rate of 0.03% per cycle is achieved. The anion’s and cation’s co-substitutions thermodynamically reduce conversion reaction potential and shift the reaction from less-reversible intercalation-conversion reaction in iron fluoride to a highly reversible intercalation-extrusion reaction in doped material. The co-substitution strategy to tune the thermodynamic features of the reactions could be extended to other high energy conversion materials for improved performance., Poor electrochemical reversibility of the conversion-type cathode materials remains an important challenge for their practical applications. Here, the authors report a highly reversible fluoride cathode material with low hysteresis through concerted doping of cobalt and oxygen into iron fluoride.

A series of novel symmetric or unsymmetric silicon (IV) phthalocyanines axially substituted with cyclic Arg-Gly-Asp (cRGD) ligands through different ethylene glycol chains have been synthesized by a facile and mild “click” reaction. All the compounds show efficient photosensitizing activities in N,N-dimethylformamide, and are essentially non-aggregated in RPMI 1640 medium with 0.05% Cremophor EL. Owing to the presence of two cRGD ligands, the conjugate 6b exhibits highest selectivity toward αvβ3+ HT-29 cells in photocytotoxicities. It shows higher cellular uptake and ROS generation efficiency toward the αvβ3+ HT-29 cells compared with that of αvβ3- MCF-7 cells. The competitive cellular uptake and subcellular localization indicate that 6b is internalized mainly through integrin-mediated endocytosis. In addition, the in vivo studies showed that 6b can mainly accumulate in tumor sites and show a significant PDT effect resulting in 75% tumor growth inhibition. The results indicate that 6b is a highly promising photosensitizer for targeted photodynamic therapy.

Nicotinamide phosphoribosyltransferase (NAMPT) possesses various functions in human cells, and altered NAMPT expression is associated with human carcinogenesis. The present study detected the expression of NAMPT in normal and cancerous breast tissues from 83 patients using immunohistochemistry, and analyzed its association with the clinicopathological and survival data of the patients. NAMPT was significantly overexpressed in the breast invasive ductal carcinoma tissues compared with adjacent normal mammary gland tissues. Upregulated NAMPT expression was associated with a larger tumor size, lymph node metastasis, advanced clinical tumor-node-metastasis stages, and estrogen receptor and progesterone receptor expression. Furthermore, NAMPT expression was associated with poor overall and disease-free survival in patients with breast cancer. In conclusion, NAMPT increased protein expression in tumor cells may contribute to the development and progression of breast invasive ductal carcinoma. Thus, detection of NAMPT expression might be useful as a biomarker for the early detection and prognosis prediction of breast cancer.

With the correlation between Li+ solvation and interphasial chemistry on anodes firmly established in Li-ion batteries, the effect of cation–solvent interaction has gone beyond bulk thermodynamic and transport properties and become an essential element that determines the reversibility of electrochemistry and kinetics of Li-ion intercalation chemistries. As of now, most studies are dedicated to the solvation of Li+, and the solvation of anions in carbonate-based electrolytes and its possible effect on the electrochemical stability of such electrolytes remains little understood. As a mirror effort to prior Li+ solvation studies, this work focuses on the interactions between carbonate-based solvents and two anions (hexafluorophosphate, PF6–, and tetrafluoroborate, BF4–) that are most frequently used in Li-ion batteries. The possible correlation between such interaction and the interphasial chemistry on cathode surface is also explored.

The two-steps method was carried out to synthesise Ag modified the hybrids of Mg-doped ZnO and reduced graphene oxide (MgZnO/RGO-Ag). The average particles size of MgZnO was determined to be 15–20 nm. The reduced graphene oxide and Ag metal was confirmed to be deposited on the surface of MgZnO. It is obvious that MgZnO/RGO nanoparticles with 2 wt-% Ag-modified exhibit much higher and quicker photocatalytic activities compared to MgZnO/RGO nanocomposites, about 30% higher rate than that of MgZnO/RGO for the degradation of methylene blue under ultraviolet light irradiation for 5 minutes. With the irradiation time increasing to 15 minutes, MgZnO/RGO-Ag nanocomposites could completely degrade the methylene blue solution. Band gap widening by Mg-doping and efficient electron–hole separation induced by reduced graphene oxide and Ag metal were identified as the main factors responsible for the enhanced sunlight-driven photocatalytic activities of MgZnO/RGO-Ag.

Polystyrene-derived carbon with hierarchical macro–meso–microporous structure was prepared via a simple template-free method. As anode materials for lithium-ion batteries, the as-prepared hierarchical porous carbon (HPC) exhibited good electrochemical performance, attaining a stable capacity of 410 mAh g−1 for over 100 cycles. It was also highlighted that, HPC showed an excellent high-rate performance in contrast to other amorphous carbon materials. These good lithium storage performances could be attributed to the developed nanostructures of HPC: (1) The continuous macro-/meso-pores were believed to facilitate rapid ion transport by serving as ion-buffering reservoirs/ion-transport pathways, especially at high current densities; (2) The small-sized nanopores including small mesopores and micropores in carbon nanoparticles provided many active sites for Li+ storage reaction; and (3) The as-constructed continuous carbon nanonetwork also represented an excellent conductive skeleton throughout the material. We hope that this class of HPC provides new opportunities for anode materials of LIBs.

This paper mainly investigates the creep property of polyurethane composites. The polyurethane composites with different structures are first prepared and experiments are subsequently carried out to study their creep property in terms of molecular weight of soft segments, isocyanate structure and cross-linking degree. The results show that the creep property gradually gets poorer with the increase of molecular weight of soft-segment polyols. The isocyanate molecule features a well-defined structure, and better anti-creep property of polyurethane materials can be observed in better orderly arranged molecular chains. Besides, higher cross-linking degree would lead to better anti-creep property of the polyurethane materials. As a result, the experimental result suggests a reasonable formula when designing to improve the anti-creep property of polyurethane materials.

The pyrene-appended dipicolylamine ligand (L) and its Cu(II) and Pt(II) compounds have been synthesized and characterized by elemental analysis, 1H- and 13C-NMR, HRMS, FT–IR and UV–Vis analyses. Furthermore, the crystal structures of H2L·2ClO4, [(CuLClO4CH3CN)ClO4] and [(PtLCl)DMSO] (DMSO = dimethyl sulfoxide) have been determined by single-crystal X-ray diffraction. The antimicrobial activities of these compounds were determined towards Gram-positive (Staphylococcus aureus ATCC-25923) and Gram-negative (Escherichia coli ATTC-25922) strains of bacteria, as well as the fungal strain Candida albicans ATCC-10213, and the results were compared with those of L alone. The results of these experiments showed that the Cu(II) and Pt(II) compounds of L exhibited stronger antibacterial and antifungal activities than the ligand.

Superoxide reacts with carbonate solvents in Li–air batteries. Tris(pentafluorophenyl)borane is found to catalyze a more rapid superoxide (O2−) disproportionation reaction than the reaction between superoxide and propylene carbonate (PC). With this catalysis, the negative impact of the reaction between the electrolyte and O2− produced by the O2 reduction can be minimized. A simple kinetic study using ESR spectroscopy was reported to determine reaction orders and rate constants for the reaction between PC and superoxide, and the disproportionation of superoxide catalyzed by Tris(pentafluorophenyl)borane and Li ions. The reactions are found to be first order and the rate constants are 0.033 s−1 M−1, 0.020 s−1 M−1 and 0.67 s−1 M−1 for reactions with PC, Li ion and Tris(pentafluorophenyl)borane, respectively.

High rate capability and long cycle life are challenging goals for the development of room temperature sodium-ion batteries. Here we report a new single phase quaternary O3-type layer-structured transition metal oxide Na(NiCoFeTi)1/4O2 synthesized by a simple solid-state reaction as a new cathode material for sodium-ion batteries. It can deliver a reversible capacity of 90.6 mA h g−1 at a rate as high as 20C. At 5C, 75.0% of the initial specific capacity can be retained after 400 cycles with a capacity-decay rate of 0.07% per cycle, demonstrating a superior long-term cyclability at high current density. X-ray diffraction and absorption characterization revealed reversible phase transformations and electronic structural changes during the Na+ deintercalation/intercalation process. Ni, Co and Fe ions contribute to charge compensation during charge and discharge. Although Ti ions do not contribute to the charge transfer, they play a very important role in stabilizing the structure during charge and discharge by suppressing the Fe migration. In addition, Ti substitution can also smooth the charge–discharge plateaus effectively, which provides a potential advantage for the commercialization of this material for room temperature sodium-ion batteries.

2D vanadium carbide MXene containing surface functional groups (denoted as V2CTx, where Tx are surface functional groups) is synthesized and studied as anode material for Na-ion batteries. V2CTx anode exhibits reversible charge storage with good cycling stability and high rate capability through electrochemical test. The charge storage mechanism of V2CTx material during Na+ intercalation/deintercalation and the redox reaction of vanadium are studied using a combination of synchrotron based X-ray diffraction, hard X-ray absorption near edge spectroscopy (XANES), and soft X-ray absorption spectroscopy (sXAS). Experimental evidence of a major contribution of redox reaction of vanadium to the charge storage and the reversible capacity of V2CTx during sodiation/desodiation process are provided through V K-edge XANES and V L2,3-edge sXAS results. A correlation between the CO32− content and the Na+ intercalation/deintercalation states in the V2CTx electrode observed from C and O K-edge in sXAS results implies that some additional charge storage reactions may take place between the Na+-intercalated V2CTx and the carbonate-based nonaqueous electrolyte. The results of this study provide valuable information for the further studies on V2CTx as anode material for Na-ion batteries and capacitors.

Lithium-rich layer-structured oxides xLi(2)MnO(3)center dot(1-x)LiMO2 (0 < x < 1, M=Mn, Ni, Co, etc.) are interesting and potential cathode materials for high energy-density lithium ion batteries. However, the characteristic charge compensation contributed by O2- in Li2MnO3 leads to the evolution of oxygen during the initial Li+ ion extraction at high voltage and voltage fading in subsequent cycling, resulting in a safety hazard and poor cycling performance of the battery. Molybdenum substitution was performed in this work to provide another electron donor and to enhance the electrochemical activity of Li2MnO3-based cathode materials. X-ray diffraction and adsorption studies indicated that Mo5+ substitution expands the unit cell in the crystal lattice and weakens the Li-O and Mn-O bonds, as well as enhancing the activity of Li2MnO3 by lowering its delithiation potential and suppressing the release of oxygen. In addition, the chemical environment of O2- ions in molybdenum-substituted Li2MnO3 is more reversible than in the unsubstituted sample during cycling. Therefore molybdenum substitution is expected to improve the performances of the Li2MnO3-based lithium-rich cathode materials.

Electric-powered transportation requires an efficient, low-cost, and safe energy storage system with high energy density and power capability. Despite its high specific capacity, the current commercially available cathode material for today's state-of-art Li-ion batteries, lithium nickel–manganese–cobalt oxide Li[Ni 1/3 Mn 1/3 Co 1/3 ]O 2 (NMC), suffers from poor cycle life for high temperature operation and marginal rate capability resulting from irreversible degradation of the cathode material upon cycling. Using an atomic-scale surface engineering, the performance of Li[Ni 1/3 Mn 1/3 Co 1/3 ]O 2 in terms of rate capability and high temperature cycle-life is significantly improved. The Al 2 O 3 coating deposited by atomic layer deposition (ALD) dramatically reduces the degradation in cell conductivity and reaction kinetics. This durable ultra-thin Al 2 O 3 -ALD coating layer also improves stability for the NMC at an elevated temperature (55 °C). The experimental results suggest that a highly durable and safe cathode material enabled by atomic-scale surface modification could meet the demanding performance and safety requirements of next-generation electric vehicles.

We explore structural changes of the carbon in MnO2/reduced graphene oxide (RGO) hybrid materials prepared by the direct redox reaction between carbon and permanganate ions (MnO4–) to reach better understanding for the effects of carbon corrosion on carbon loss and its bonding nature during the hybrid material synthesis. In particular, we carried out near-edge X-ray absorption fine structure spectroscopy at the C K-edge (284.2 eV) to show the changes in the electronic structure of RGO. Significantly, the redox reaction between carbon and MnO4– causes both quantitative carbon loss and electronic structural changes upon MnO2 deposition. Such disruptions of carbon bonding have a detrimental effect on the initial electrical properties of the RGO and thus lead to a significant decrease in electrical conductivity. Electrochemical measurements of the MnO2/reduced graphene oxide hybrid materials using a cavity microelectrode revealed unfavorable electrochemical properties that were mainly due to the poor electric...

The effects on electrochemical performance of C14H8O2 organic cathode materials with and without SO3Na– functional groups for lithium ion batteries were investigated. The Na2C14H6O8S2 with two SO3Na– shows the best cycle performance and highest lithium storage voltage, while an outstanding rate performance is also achieved after combination with graphene paper.

An efficient method for the synthesis of asymmetric tripodal ligands from aryl aldehydes and (2-hydro-xybenzyl-2-pyri-dylmethyl)amine was developed. It has the advantages of short reaction times, high yields and a simple methodology. The title ligands were characterized using a combination of 1H NMR, 13C NMR, FT-IR and H RMS spectroscopies. The structures of some of the ligand were confirmed by single-crystal X-ray diffraction.

For the first time, electrochemically generated superoxide ions on a porous carbon electrode are investigated by means of in situ electrochemical ESR technique at ambient conditions. Superoxide ions ( O 2 · − ) are detected as the product of the electrochemical O2 reduction reaction. The redox couple (O2/ O 2 · − ) is reversible in DMSO electrolyte. The superoxide ions are believed to be absorbed and de-mobilized on the carbon surface. Overlapping a symmetric carbon ESR signal, the anisotropic signal of the superoxide is observed. The g-factor of the carbon ESR spectra is found to be 2.0025, which is almost identical to that of a free electron; Anisotropic g-factors for the O 2 · − are g⊥ = 2.0031, g// = 2.0750.

We first report the ultra-fast charge–discharge capability of organic–inorganic (Li(Mn 1/3 Ni 1/3 Fe 1/3 )O 2 –Polyaniline (PANI)) nanocomposites prepared by mixed hydroxide route and followed by polymerization of aniline monomers with different concentrations (0.1 and 0.2 mol concentration of PANI). Li-insertion properties are evaluated in half-cell configuration, test cell (Li/Li(Mn 1/3 Ni 1/3 Fe 1/3 )O 2 –PANI) comprising 0.2 mol. PANI delivered the reversible capacity of ∼127, ∼114 and ∼110 mAh g −1 at ultra-high current rate of 5, 30 and 40 C, respectively with exceptional cycleability between 2 and 4.5 V vs. Li. Such an exceptional performance is mainly due to the conducting pathways promoted by PANI network and it is revealed by impedance measurements. This result certainly provides the possibility of using such layered type Fe based cathode materials in high power Li-ion batteries to drive zero emission vehicles such as hybrid electric vehicles or electric vehicles applications in near future.

Tris(pentafluorophenyl)borane (TPFPB) was found to be an efficient catalyst for rapid superoxide (O2(-)) disproportionation. The kinetics for the catalytic disproportionation reaction is much faster than the reaction between O2(-) and propylene carbonate. Therefore, the negative impact of the reaction between the electrolyte and O2(-) produced by the O2 reduction is minimized. The cathodic current for O2 reduction can be doubled in the presence of TPFPB. The high reduction current resulted from the pseudo two-electron O2-reduction reaction due to the replenishment of O2 at the electrode surface. This discovery could lead to a new avenue for the development of high-capacity, high-rate, rechargeable Li-air batteries.