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Alkali metal‐ion capacitors integrate two electrodes from both batteries and supercapacitors (SCs), combining the advantages of large capacity, high‐rate performance, and long cycle life. Potassium (K) has similar properties to sodium (Na) and lithium (Li), however, the abundance of K in the crust is the same with Na, and much higher than Li. Due to the fast kinetics and low self‐discharge of Potassium‐ion capacitors (PICs), PICs attract more interest from researchers in the field of electrochemical energy storage. The current dilemma is that the research on PICs is more inherited from sodium‐ion capacitors (SICs) and lithium‐ion capacitors (LICs). Despite advancements in electrode materials, there is still a lack of profound understanding of the intrinsic issues and key challenges of PICs. In order to provide a detailed and systematic analysis of the development of PICs, in this review, special attention is given on the following Accordingly, full eight key sections: i) development history, ii) defining equations, iii) energy storage mechanism, iv) device configuration, v) electrode materials, vi) electrolyte design, vii) key technologies, and viii) future perspectives. This review provides an intensive theoretical foundation for the development of PICs and is able to pave the path for the practical application of PICs. [ABSTRACT FROM AUTHOR]

TiS2 has received significant attention as a promising anode for "Rocking‐Chair"‐type aqueous Zn‐ion batteries due to the large interlayer spacing and low discharge plateau. However, the structural distortion caused by the embedding of divalent Zn2+ as well as the undesirable hydrogen evolution reaction (HER) severely affects their cycling stability. Herein, a facet‐dependent mechanism is first deeply investigated to understand charge storage behaviors of TiS2 via differential electrochemical mass spectrometry, in situ electrochemical quartz crystal microbalance, and in situ X‐ray diffraction characterizations. By regulating the exposed crystal facets of TiS2 from (001) (TS (001)) to (011) (TS(011)), HER can be effectively inhibited, and the charge storage mechanism is transformed from Zn2+ insertion/extraction dominating to H+ insertion/extraction dominating, resulting in faster charge transfer kinetics and strong structure stability during long‐term cycling. Hence, TS(011) delivers a higher reversible capacity of 212.9 mAh g−1 at 0.1 A g−1 and a strong cycling stability of 74% capacity retention over 1000 cycles, much better than that of TS (001) with a reversible capacity of 164.7 mAh g−1 at 0.1 A g−1, a capacity retention of 17% after 1000 cycles. These new findings can provide deep insight into the rational design of high‐performance intercalation‐type electrode materials for energy storage applications. [ABSTRACT FROM AUTHOR]

The aggravation of energy problems and the scarcity of lithium resources have forced us to look for new energy storage systems. Aluminum ion batteries, as a promising energy storage system, have the advantages of environmental friendliness and abundant aluminum resources, and have the potential for application in large‐scale energy storage and personal portable electronic devices. To solve the stability problem of aluminum ion batteries during cycling for large‐scale energy storage needs, we report a polythiophene‐based conductive polymer, poly(3,4‐dimethylthiophene) (PDMT), as a high performance cathode material for aluminum ion batteries. By introducing two methyl groups on the thiophene ring, we successfully adjust the local charge density of the heterocyclic thiophene, thus changing the electron delocalization characteristics, and improving the electrochemical reaction activity of the polythiophene (PTH) material as a redox electrode material. This also maintains the symmetry and regularity of the polymer structure, giving the material better cycling stability. The discharge specific capacity reaches 110 mAh g−1 at a current density of 200 mA g−1, far exceeding conventional PTH cathodes (~70 mAh g−1), and the capacity retention rate is 92.7 % after 1000 cycles. It also shows excellent rate performance due to the flexible structure of the conductive polymer. [ABSTRACT FROM AUTHOR]

Although Prussian blue analogues are the promising candidate cathode materials for the Na‐ion batteries for the grid storage due to 3D open‐framework structure and large interstitial "A" sites, high content of defects in the crystals obtained in the conventional strategy severely impede Na+ migration, leading to an unsatisfactory power density. Here a novel epitaxial nucleation‐assisted controlled crystallization approach to eliminate the structural defects of NaFeHCF crystals is reported. Due to their limited lattice misfit of only 4.87% (< 5%) between the graphene and NaFeHCF as well as the electronegativity of the functional groups (─COOH, ─OH, ─CH(O)CH─), GO can act as the nucleation and subsequent epitaxial growth platform of NaFeHCF, which results in a unique one‐corner‐cut cubic nano‐crystals morphologies with much decreased contents of defects (0.08 per formula unit). This enhanced lattice regularity significantly enhanced the speedy diffusion of Na cations (by 5 times) in the nanocrystals, resulting in the unprecedented rate capability of 96.8 mAh g−1 at an ultra‐high rate of 9 A g−1 (39 s, 23228 W kg−1), which is far exceeding that of any previously reported PBA‐based cathodes to the knowledge, authenticating its superiority as a candidate for high‐power sodium‐ion batteries for the reliable grid energy storage. [ABSTRACT FROM AUTHOR]

Designing flexible free‐standing air‐electrode with efficient OER/ORR performance is of vital importance for the application of Zinc‐air batteries in flexible electronics. Herein, a flexible free‐standing electrode (Ni/Fe‐NC/NCF/CC) is synthesized by in‐situ coupling of binary Ni/Fe‐NC nanocubes and N‐doped carbon nanofibers (NCF) rooted on carbon cloth. The highly dispersed binary Ni/Fe‐NC sites ensure excellent ORR activity and create efficient OER active sites relative to Ni‐NC and Fe‐NC. The in‐situ coupling of Ni/Fe‐NC and NCF constructs a 3D interconnected network structure that not only provides abundant and stabilized reactive sites but also guarantees fast electron transfer and gas transportation, thus achieving efficient and fast operation of ORR/OER. Therefore, Ni/Fe‐NC/NCF/CC displays a much positive potential (0.952 V) at 4.0 mA cm−2 for ORR and a low OER overpotential (310 mV) at 50 mA cm−2. The Zinc‐air battery with Ni/Fe‐NC/NCF/CC air‐electrode exhibits excellent battery performance with outstanding discharge/charge durability for 2150 cycles. The flexible Zn‐air batteries with foldable mechanical properties display a high power density of 105.0 mW cm−2. This work widened the way to prepare flexible bifunctional air‐electrode by designing composition/structure and in‐situ coupling. [ABSTRACT FROM AUTHOR]

Recent advances in single-cell technologies have led to the discovery of thousands of brain cell types; however, our understanding of the gene regulatory programs in these cell types is far from complete1–4. Here we report a comprehensive atlas of candidate cis-regulatory DNA elements (cCREs) in the adult mouse brain, generated by analysing chromatin accessibility in 2.3 million individual brain cells from 117 anatomical dissections. The atlas includes approximately 1 million cCREs and their chromatin accessibility across 1,482 distinct brain cell populations, adding over 446,000 cCREs to the most recent such annotation in the mouse genome. The mouse brain cCREs are moderately conserved in the human brain. The mouse-specific cCREs—specifically, those identified from a subset of cortical excitatory neurons—are strongly enriched for transposable elements, suggesting a potential role for transposable elements in the emergence of new regulatory programs and neuronal diversity. Finally, we infer the gene regulatory networks in over 260 subclasses of mouse brain cells and develop deep-learning models to predict the activities of gene regulatory elements in different brain cell types from the DNA sequence alone. Our results provide a resource for the analysis of cell-type-specific gene regulation programs in both mouse and human brains.An atlas of candidate cis-regulatory DNA elements (cCREs) in the adult mouse brain unravels the transcriptional regulatory programs that drive the heterogeneity and complexity of brain structure and function. [ABSTRACT FROM AUTHOR]

Vanadium redox flow batteries (VRFBs) have become increasingly popular for energy storage, owing to their exceptional safety and scalability. However, the electrode material drawbacks still restrict the efficiency of the VRFBs. In this study, we employed atmospheric dielectric barrier discharge (DBD) to modify the commercial carbon felt (CF) electrodes for VRFB efficiency improvement. The treatment conditions were optimized by changing the gas composition and the treatment time. We found that the DBD modification could effectively enhance the coulombic efficiency (CE), voltage efficiency (VE), and energy efficiency (EE) of VRFB, and the improvements increased with the increase in N2:O2 ratio and the treatment time. The most significant EE improvement was ~ 13.2% after 10 min DBD treatment. The electrolyte contact angle decreased with the treatment time and closely related to the battery efficiency. The X-ray photoelectron spectroscopy (XPS) results demonstrated that plasma treatment formed abundant hydrophilic functional groups, while the scanning electron microscope (SEM) results shown increased roughness on the CF surface. All the results indicated the DBD modification introduces hydrophilic groups onto the CF surface and increases the roughness, which could increase the reaction area and provide more active sites for the vanadium redox reaction hence enhance the VRFB efficiency. [ABSTRACT FROM AUTHOR]

In this article, a systematic examination of the electronic and optical properties of partially fluorinated graphene is presented. In order to capture a large variety of fluorination degrees and configurations, different sizes of the supercell combining with various degrees of fluorination are considered. On top of periodic density functional theory, the G0W0 method and the G0W0Γ method within many-body Green's function framework are employed. Including the description of electron–hole interactions, the optical spectra based on the Bethe–Salpeter equation are calculated. Two-sided fluorination with compact fluorination arrangements is energetically most favorable. The fluorination degree has a determined impact on the bandgap value in the system, while the fluorination pattern strongly influences the characteristics of the bands in the electronic structures. Depending on the polarization of the applied electromagnetic field, the optical absorption spectra of the same structure could vary significantly. These interesting results suggest the potential applications of partially fluorinated graphene as optoelectronic materials. [ABSTRACT FROM AUTHOR]

Dysfunction of glucagon-secreting α-cells participates in the progression of diabetes, and glucagon receptor (GCGR) antagonism is regarded as a novel strategy for diabetes therapy. GCGR antagonism upregulates glucagon and glucagon-like peptide 1 (GLP-1) secretion and, notably, promotes β-cell regeneration in diabetic mice. Here, we aimed to clarify the role of GLP-1 receptor (GLP-1R) activated by glucagon and/or GLP-1 in the GCGR antagonism–induced β-cell regeneration. We showed that in db/db mice and type 1 diabetic wild-type or Flox/cre mice, GCGR monoclonal antibody (mAb) improved glucose control, upregulated plasma insulin level, and increased β-cell area. Notably, blockage of systemic or pancreatic GLP-1R signaling by exendin 9-39 (Ex9) or Glp1r knockout diminished the above effects of GCGR mAb. Furthermore, glucagon-neutralizing antibody (nAb), which prevents activation of GLP-1R by glucagon, also attenuated the GCGR mAb–induced insulinotropic effect and β-cell regeneration. In cultured primary mouse islets isolated from normal mice and db/db mice, GCGR mAb action to increase insulin release and to upregulate β-cell–specific marker expression was reduced by a glucagon nAb, by the GLP-1R antagonist Ex9, or by a pancreas-specific Glp1r knockout. These findings suggest that activation of GLP-1R by glucagon participates in β-cell regeneration induced by GCGR antagonism in diabetic mice. Article Highlights: Glucagon receptor (GCGR) antagonism promotes β-cell regeneration in type 1 and type 2 diabetic mice and in euglycemic nonhuman primates. Glucagon and glucagon-like peptide 1 (GLP-1) can activate the GLP-1 receptor (GLP-1R), and their levels are upregulated following GCGR antagonism. We investigated whether GLP-1R activated by glucagon and/or GLP-1 contributed to β-cell regeneration induced by GCGR antagonism. We found that blockage of glucagon–GLP-1R signaling attenuated the GCGR monoclonal antibody–induced insulinotropic effect and β-cell regeneration in diabetic mice. Our study reveals a novel mechanism of β-cell regeneration and uncovers the communication between α-cells and β-cells in regulating β-cell mass. [ABSTRACT FROM AUTHOR]

Lithium metal is recognized as a promising anode material for next-generation high-energy-density batteries, but uncontrollable lithium dendrites inhibit their further applications. In this paper, fluorine-containing functional groups were grafted on a commercial polypropylene (PP) separator by a simple and efficient plasma functionalization technique. The grafted polar groups enhance the affinity of the PP separator for Li-ions, thus resulting in improved wettability and ion conductivity as well as an enhanced lithium-ion transference number of the separator. Moreover, the introduced fluorine-containing functional groups participate in the formation of a LiF-rich solid electrolyte interface (SEI) film, which regulates the uniform deposition of lithium ions and inhibits lithium dendrite growth. As a result, Li‖Li symmetric batteries equipped with fluorinated PP separators exhibit a long lifespan of nearly 7000 h (1 mA cm−2, 1 mA h cm−2) with a low overpotential of 48 mV. This work introduces a simple method to induce the formation of a LiF-rich SEI film, which can be extended to a variety of energy storage systems and provides new routes for the construction of high-performance energy storage technologies. [ABSTRACT FROM AUTHOR]

Aims: Sodium‐glucose co‐transporter 2 inhibitors, including dapagliflozin, improve ß cell function in type 2 diabetic individuals. Whether dapagliflozin can protect islet microvascular endothelial cells (IMECs) and thus contribute to the improvement of ß cell function remains unknown. Materials and Methods: The db/db mice were treated with dapagliflozin or vehicle for 6 weeks. ß cell function, islet capillaries and the levels of inflammatory chemokines in IMECs were detected. The mouse IMEC cell line MS‐1 cells were incubated with palmitate and/or dapagliflozin for 24 h. Angiogenesis and inflammatory chemokine levels were evaluated, and the involved signalling pathways were analysed. The mouse ß cell line MIN6 cells, in the presence or absence of co‐culture with MS‐1 cells, were treated with palmitate and/or dapagliflozin for 24 h. The expression of ß cell specific markers and insulin secretion in MIN6 cells were determined. Results: Dapagliflozin significantly improved ß cell function, increased islet capillaries and decreased the levels of inflammatory chemokines of IMECs in db/db mice. In the palmitate‐treated MS‐1 cells, angiogenesis was enhanced and the levels of inflammatory chemokines were downregulated by dapagliflozin. Either a PI3K inhibitor or mTOR inhibitor eliminated the dapagliflozin‐mediated effects. Importantly, dapagliflozin attenuated the palmitate‐induced downregulation of ß cell function‐related gene expression and insulin secretion in MIN6 cells co‐cultured with MS‐1 cells but not in those on mono‐culture. Conclusions: Dapagliflozin restores islet vascularisation and attenuates the inflammation of IMECs in type 2 diabetic mice. The dapagliflozin‐induced improvement of ß cell function is at least partially accounted for by its beneficial effects on IMECs in a PI3K/Akt‐mTOR‐dependent manner. [ABSTRACT FROM AUTHOR]

The structure and electronic properties of the molybdenum disulfide (MoS2) monolayer upon water cluster adsorption are studied using density functional theory and the optical properties are further analyzed with the Bethe–Salpeter equation (BSE). Our results reveal that the water clusters are electron acceptors, and the acceptor tendency tends to increase with the size of the water cluster. The electronic band gap of both pristine and defective MoS2 is rather insensitive to water cluster adsorbates, as all the clusters are weakly bound to the MoS2 surface. However, our calculations on the BSE level show that the adsorption of the water cluster can dramatically redshift the optical absorption for both pristine and defective MoS2 monolayers. The binding energy of the excitons of MoS2 is greatly enhanced with the increasing size of the water cluster and finally converges to a value of approximately 1.16 eV and 1.09 eV for the pristine and defective MoS2 monolayers, respectively. This illustrates that the presence of the water cluster could localize the excitons of MoS2, thereby greatly enhance the excitonic binding energy. [ABSTRACT FROM AUTHOR]

Previously, we have proposed a method, FPA-M, for focal-point analysis of magnetic parameter calculations [Sun et al., J. Chem. Phys. 138, 124113 (2013)], where the shielding constants at equilibrium geometries σe are calculated with the second order Møller-Plesset perturbation (MP2) approach, which are extrapolated to the complete basis set (CBS) limit and then augmented by the [σe(CCSD(T)) − σe(MP2)] difference at a valence triple-ζ (VTZ) basis set, where CCSD(T) stands for the coupled cluster singles and doubles model with a perturbative correction for triple excitations. This FPA-M(MP2) method provides satisfactory results to approach to the corresponding CCSD(T)/CBS values for elements of the first two rows in the periodic tables. A series of extensions have been explored here, which replace the MP2/CBS with the Hartree-Fock (HF)/CBS for efficiency. In particular, the [σe(CCSD(T)) − σe(MP2)] VTZ difference is replaced by a step-wise correction from the [σe(CCSD(T)) − σe(MP2)] difference at a valence double-ζ basis set plus the [σe(MP2) − σe(HF)] VTZ difference, leading to a new scheme, denoted here as FPA-M(HF′). A systematical comparison has demonstrated that the FPA-M(HF′) method provides an excellent balance between accuracy and efficiency, which makes routinely accurate calculations of the shielding constants for medium-sized organic molecules and biomolecules feasible. [ABSTRACT FROM AUTHOR]

It is instructive to explain the mechanism of action of additives as much as possible for the development of electrolytes. Recently, lithium disfluorobis(oxalato)phosphate (LiDFBOP) has been reported to show significant improvements in the solid electrolyte interphase (SEI) and battery performance in Li–S battery. In this work, the action mechanism of LiDFBOP in ether electrolyte was investigated in detail by a first-principles study. It was found that LiDFBOP preferentially decomposes on the anode, and the local environment after decomposition has a significant influence on the subsequent reaction. In addition, the participation of DFBOP− significantly affected the solvated structure and the trend in molecular decomposition. The addition of appropriate LiDFBOP weakened the strong binding between Li ion and the FSI− anion, and increased the content of 1,3-dioxolane in the solvated structure, thus improving the formation of the organic SEI. On the other hand, the LUMO redistribution induced by LiDFBOP is beneficial for protection of solvents. The possible characteristics of the new additive and the importance of dosage are also summarized in terms of the mechanism of action. [ABSTRACT FROM AUTHOR]

The practical application of infancy‐stage rocking‐chair Zn‐ion batteries is predominately retarded by the strong electrostatic interaction between traditional anode materials with bivalent Zn2+, resulting in irreversible serious structural damage, unsatisfactory cycling stabilities, and poor rate performances. Herein, an advanced dual electric field in situ induced intercalation/conversion dual‐mechanism Na1.6TiS2/CuSe2 heterointerface anode towards ultrastable aqueous rocking‐chair zinc‐ion batteries is successfully constructed. The rational constructions of huge heterointerfaces between different phases generate built‐in electric fields, reducing the energy barrier for ion migration, facilitating electron/ion diffusion, decreasing charge transfer resistances, and establishing an excellent conducting network. The enhanced interactions of different atoms at the phase interface alleviate the tensile strain and stabilize the lattice, achieving superior Zn2+ diffusion kinetics. The dual‐mechanism Na1.6TiS2/CuSe2 heterostructures can reach a discharge capacity of 142 mAh g−1 at 0.2 A g−1. It still reaches a discharge capacity of 133 mAh g−1 when the current density recovers to 0.2 A g−1 after a high current evaluation of 10 A g−1 with remarkable capacity retention (83.8% at 5A g−1 after 12 000 cycles). This breakthrough opens a new avenue for the targeted design of rocking‐chair zinc‐ion batteries and provides insights into the evolution of heterointerfaces. [ABSTRACT FROM AUTHOR]

DNA methylation (DNAm) that occurs on promoter regions is primarily considered to repress gene expression. Previous studies indicated that DNAm could also show positive correlations with gene expression. Both DNAm and gene expression profiles are known to be tissue- and development-specific. This study aims to investigate how DNAm and gene expression are coordinated across different human tissues and developmental stages, as well as the biological significance of such correlations. By analyzing 2,239 samples with both DNAm and gene expression data in the same human subjects obtained from six published datasets, we evaluated the correlations between gene and CpG pairs (GCPs) at cis-regions and compared significantly correlated GCPs (cGCPs) across different tissues and brains at different age groups. A total of 37,363 cGCPs was identified in the six datasets; approximately 38% of the cGCPs were positively correlated. The majority (>90%) of cGCPs was tissue- or development-specific. We also observed that the correlation direction can be opposite in different tissues and ages. Further analysis highlights the importance of cGCPs for their cellular functions and potential roles in complex traits and human diseases. For instance, the early developmental brain possessed a highly unique set of cGCPs that were associated with neurogenesis and psychiatric disorders. By assessing the epigenetic factors involved in cGCPs, we discovered novel regulatory mechanisms of positive cGCPs distinct from negative cGCPs, which were related to multiple factors, such as H3K27me3, CTCF, and JARD2. The catalogue of cGCPs compiled can be used to guide functional interpretation of genetic and epigenetic studies. [ABSTRACT FROM AUTHOR]

Background and Hypothesis Although large-scale neuroimaging studies have demonstrated similar patterns of structural brain abnormalities across major psychiatric disorders, the underlying genetic etiology behind these similar cross-disorder patterns is not well understood. Study Design We quantified the extent of shared genetic components between cortical structures and major psychiatric disorders (CS-MPD) by using genome-wide association study (GWAS) summary statistics of 70 cortical structures (surface area and thickness of the whole cortex and 34 cortical regions) and five major psychiatric disorders, consisting of attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), bipolar disorder (BD), major depressive disorder (MDD), and schizophrenia (SCZ). Cross-disorder analyses were then conducted to estimate the degree of similarity in CS-MPD shared genetic components among these disorders. Study Results The CS-MPD shared genetic components have medium-to-strong positive correlations in ADHD, BD, MDD, and SCZ (r  = 0.415 to r  = 0.806) while ASD was significantly correlated with ADHD, BD, and SCZ (r  = 0.388 to r  = 0.403). These pairwise correlations of CS-MPD shared genetic components among disorders were significantly associated with corresponding cross-disorder similarities in cortical structural abnormalities (r  = 0.668), accounting for 44% variance. In addition, one latent shared factor consisted primarily of BD, MDD, and SCZ, explaining 62.47% of the total variance in CS-MPD shared genetic components of all disorders. Conclusions The current results bridge the gap between shared cross-disorder heritability and shared structural brain abnormalities in major psychiatric disorders, providing important implications for a shared genetic basis of cortical structures in these disorders. [ABSTRACT FROM AUTHOR]

Lithium metal anodes have long been considered as "holy grail" in the field of energy storage batteries, but dendrite growth and large volume changes hinder their practical applications. Herein, a facile and eco‐friendly CF4 plasma treatment is employed for the surface modification of Li anodes, and an artificial layer consisting of LiF and Li2C2 is fabricated for the first time. Experimental results and theoretical calculations reveal that the high adsorption energy of LiF and low Li+ diffusion barriers in Li2C2 induce uniform nucleation and planar growth of Li, guaranteeing a stable and dendrite‐free Li structure during the repeated plating/stripping process of cycling. Symmetric cells using CF4 plasma‐treated Li operate stably for more than 6500 h (at 2 mA cm−2 and 1 mAh cm−2) or 950 h (at 1 mA cm−2 and 10 mAh cm−2). When paired with a LiFePO4 cathode, full batteries deliver a high reversible capacity of 136 mAh g−1 (at 1 C) with considerable cycling stability (97.2% capacity retention over 200 cycles) and rate performance (116 mAh g−1 up to 5 C). This powerful application of plasma technology toward novel LiF‐Li2C2 artificial layers provide new routes for constructing environment‐friendly and high‐performance energy storage devices. [ABSTRACT FROM AUTHOR]

By employing first-principles simulations, we present theoretical predictions regarding the modification of structural, electronic and optical properties of 2H- and 1T′-MoS2 monolayers by covalent mono- and bisfunctionalization. Specifically, non-aromatic groups (–F, –NH2, –CH3, –CH2CH2 CN and –CH2CH2 OH) and aromatic (–Ph, –PhNO2 and PhOH) groups are utilized for monofunctionalization, and –F/–NH2, –NH2/–CH3 and –CH3/–Ph for bisfunctionalization. The stability of functionalized 2H- and 1T′-MoS2 monolayers mainly depends on the bonded groups and their surface coverage. In particular, the mixed bisfunctionalization with –F/–CH3 and –NH2/–CH3 groups enhances the stability of 2H-MoS2 through the formation of intermolecular hydrogen bonds. Both 2H- and 1T′-MoS2 can serve not only as electron donors, but also as electron acceptors, subject to the charge transfer behavior of the attached groups. Furthermore, mono- and bisfunctionalization are predicted to be efficient approaches to control the electronic band gaps in 2H- and 1T′-MoS2, where the corresponding values can be tuned by varying the coverage of the absorbed groups. At the same time, the choice of the chemical groups and their coverage also effectively determines the optical adsorption range and intensity. Therefore, our work shows that chemical functionalization of 2D materials with varying coverage can be an important approach to extend the scope of 2D materials in specific electronic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Constructing flexible free‐standing electrodes with efficient bifunctional performance is significant for improving the performance of flexible Zinc–air batteries. Herein, a flexible free‐standing bifunctional electrode (N2‐NiFe‐PBA/NCF/CC‐60) is constructed by the 3D spatial combination of CN vacancy‐mediated NiFe Prussian Blue Analogue (NiFe‐PBA) and N‐doped carbon nanofibers (NCF) rooted on carbon cloth (CC). The in situ formed CN vacancies by N2‐plasma activation tune the local coordination environment and electronic structure of Ni‐Fe active sites in NiFe‐PBA, thus improving the oxygen evolution reaction (OER) catalytic intrinsic activity, and restraining the loss of Fe element during OER process. The combination of NiFe‐PBA and NCF presents a 3D interworking network structure, which exhibits a large specific surface and excellent electrical conductivity, thus guaranteeing sufficient, stable, and efficient oxygen reduction reaction (ORR)/OER active sites. Therefore, the N2‐NiFe‐PBA/NCF/CC‐60 electrode delivers high‐efficiency OER activity with a low overpotential (270 mV at 50 mA cm−2) and excellent ORR performance with a positive potential of 0.89 V at 5 mA cm−2. The N2‐NiFe‐PBA/NCF/CC‐60 based Zn–air batteries display outstanding discharge/charge stability for 2000 cycles. Meanwhile, the corresponding flexible Zn–air batteries with satisfactory mechanical properties exhibit a low voltage gap of 0.52 V at 1.0 mA cm−2. [ABSTRACT FROM AUTHOR]

In this study, the metatranscriptome technology was used to study the differences in the composition and genes functions of the physiologically active bacterial and fungal communities in the strong-flavor Baijiu fermented grains (FGs) at different spatial locations of pit. The results showed that 87 phyla, 78 classes, 165 orders, 396 families, 1612 genera and 7234 species were detected in the bacterial community, and 8 phyla, 26 classes, 58 orders, 127 families, 223 genera and 394 species were detected in the fungal community. However, there was little difference in the number of active microorganisms among the top, middle and bottom layers of FGs. There was no significant difference in the bacterial and fungal community composition in each layer of FGs, with Firmicutes and Ascomycota as the main dominant bacterial and fungal phylum, respectively. Bacillus and Saccharomyces were the main dominant bacterial and fungal class, respectively. Lactobacillus was the main dominant bacterial genera, Saccharomyces (top and bottom) or Scheffersomyces (middle) was the main dominant fungal genera. Furthermore, the number of differentially-expressed genes between the bottom and middle layer, and between the middle and upper layer of FGs was higher and it was 90 and 67 respectively. And the differentially-expressed genes were mainly concentrated in RNA degradation and Glycolysis/Gluconeogenesis pathway, and most of the difference gene function between each layer was metabolism. The active microbial flora in the middle FGs had the lowest effect on RNA degradation, and the active microbial flora in the bottom FGs contributed the most to the metabolic activity. [ABSTRACT FROM AUTHOR]

High myopia is one of the leading causes of visual impairment worldwide with high heritability. We have previously identified the genetic contribution of SLC39A5 to nonsyndromic high myopia and demonstrated that disease‐related mutations of SLC39A5 dysregulate the TGF‐β pathway. In this study, the mechanisms underlying SLC39A5 involvement in the pathogenesis of high myopia are determined. We observed the morphogenesis and migration abnormalities of the SLC39A5 knockout (KO) human embryonic kidney cells (HEK293) and found a significant injury of ECM constituents. RNA‐seq and qRT‐PCR revealed the transcription decrease in COL1A1, COL2A1, COL4A1, FN1 and LAMA1 in the KO cells. Further, we demonstrated that TGF‐β signalling, the regulator of ECM, was inhibited in SLC39A5 depletion situation, wherein the activation of receptor Smads (R‐Smads) via phosphorylation was greatly blocked. SLC39A5 re‐expression reversed the phenotype of TGF‐β signalling and ECM synthesis in the KO cells. The fact that TGF‐β signalling was zinc‐regulated and that SLC39A5 was identified as a zinc transporter urged us to check the involvement of intracellular zinc in TGF‐β signalling impairment. Finally, we determined that insufficient zinc chelation destabilized Smad proteins, which naturally inhibited TGF‐β signalling. Overall, the SLC39A5 depletion–induced zinc deficiency destabilized Smad proteins, which inhibited the TGF‐β signalling and downstream ECM synthesis, thus contributing to the pathogenesis of high myopia. This discovery provides a deep insight into myopic development. [ABSTRACT FROM AUTHOR]

Phosphorus doped carbons are of particular interest as anode materials because of their large interlayer spacing and strong adsorption of Na+ ions. However, it remains challenging to achieve high phosphorus doping due to the limited choices of phosphorus sources and the difficulty in constructing oxygen‐free synthesis system. Herein, a new synthesis strategy is proposed to prepare ultrahigh phosphorus‐doped carbon (UPC) anodes for high performance sodium ion batteries (SIBs). By using two commonly available, miscible, evaporable liquids in PCl3 and C6H12, as phosphorus and carbon sources, an oxygen‐free reaction system is successfully established by N2 bubbling to simultaneously realize carbonization and in situ P doping. The P content can reach 30 wt%, much higher than most reported P‐doping carbon‐based materials. Furthermore, the doped P is dominated by substitutional P(C3) protrusions in the carbon lattice, which can significantly enlarge the interlayer spacing and enhance the adsorption energy of Na+. When serving as the SIBs anode, the UPC delivers an ultrahigh reversible capacity of 510.4 mAh g−1 with a rational operating voltage of 0.54 V, and the best rate capability of 397.1 mAh g−1 at 10 A g−1. This new strategy will effectively promote the practical application of hard carbon. [ABSTRACT FROM AUTHOR]

A series of low-valence titanium oxides (TiO and Ti2O) were fabricated by the electric field control approach and their stoichiometric ratios were precisely regulated by adjusting the electrolytic voltage and time. The Na-storage behaviours of the low-valence titanium oxides were investigated for the first time. Compared to conventional TiO2, low-valence titanium oxides undergo conversion reactions with excellent electrochemical performances. The Ti2O electrode delivers a high reversible capacity of 515 mA h g−1, outstanding rate capability of 173 mA h g−1 at 20 A g−1 and superior long-term cycling stability over 1800 cycles. Ex situ characterization reveals the reversible transformation of Ti2O to Ti and Na2O during repeated cycling. Density functional theory (DFT) calculations confirm that the low Ti–O bond energy is in favor of the fracture and recombination of Ti–O bonds, resulting in high capacity through multi-electron conversion reactions. The high conductivity of low-valence titanium oxides is conducive to the rapid transfer of electrons, achieving high electrochemical utilization. In addition, the porous nanostructure generated in situ by chemical conversion reactions could improve Na+ diffusion kinetics and buffer volume changes during sodiation/desodiation processes, thus realizing superior cycling stability and ultrafast charge/discharge ability. Moreover, a full cell coupled with a carbon-coated Na3V2(PO4)3 (Na3V2(PO4)3/C) cathode was assembled, which exhibited a high reversible capacity of 258.4 mA h g−1 and extraordinary cycling performance of 86.5% capacity retention over 100 cycles, demonstrating the potential of low-valence titanium oxides in sodium ion batteries. [ABSTRACT FROM AUTHOR]

Copper sulfide (CuS) is considered as a promising sodium storage anode with its high theoretical capacity (558 mAh g−1), low cost and environmental friendliness. However, the development of applicable CuS anodes with high rate and long life is still greatly hindered by the sluggish electronic/ionic transport kinetics and huge volume change during repeated charge/discharge processes. In this work, a scalable and binder‐free 3D porous CuS microflower (CuS‐b) electrode was prepared via a simple method with in situ sulfur engraving on commercial copper foil. The as‐prepared CuS‐b delivers a high reversible capacity of 543 mAh g−1, excellent rate capability of 413 mAh g−1 at 60 A g−1 and remarkable long‐term cycling stability of 98.2 % capacity retention over 3600 cycles. The 3D self‐supporting porous structure can increase ionic transfer kinetics and provides enough space to buffer the volume expansion/contraction during repeated cycling, resulting in excellent Na storage performances. More importantly, the synthesis path is simple and efficient, which provides new insights for the design and development of high‐performance redox‐active electrodes for large‐scale energy storage applications. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous zinc ion batteries are enabled by the (de)intercalation chemistry, but bottlenecked by the limited energy density due to the low capacity of cathodes. In this work, carbon nanotubes supported 50 wt% sulfur (denoted as S@CNTs‐50), as a conversional cathode, is employed and a high energy density aqueous zinc–sulfur (Zn–S) battery is constructed. In the electrolyte of 1 m Zn(CH3COO)2 (pH = 6.5) with 0.05 wt% I2 additive where I2 can serve as medium of Zn2+ ions to reduce the voltage hysteresis of S@CNTs‐50 and stabilize Zn stripping/plating, S@CNTs‐50 delivers a high capacity of 1105 mAh g−1 with a flat discharge voltage of 0.5 V, realizing an energy density of 502 Wh kg−1 based on sulfur, which is one of the highest values reported in aqueous Zn‐based batteries that use mild electrolyte. Moreover, the chemical materials cost of this aqueous Zn–S battery can be lowered to be $45 kWh−1 due to the cheap raw materials, reaching to the level of pumped energy storage. Ex situ X‐ray diffraction, Raman spectra, X‐ray photoelectron spectrum, and transmission electron microscopy measurements reveal that sulfur cathode undergoes a conversion reaction between S and ZnS. [ABSTRACT FROM AUTHOR]

Though high capacity and stable cycling of hard carbon anode Na-ion batteries have been achieved, critical safety issues, low discharge potential and unsatisfactory rate performance, present a huge challenge for their practical application. Herein, a slope-dominated mechanism strategy has been designed by preparing hybrid nanostructure carbon materials (HNCs) using a CVD-like method, providing hard carbon with excellent rate performances and high average discharge potential as an anode for Na-ion batteries. The HNCs integrate the advantages of carbon nanotubes and carbon nanosheets, presenting short ion/electron transfer distance and high surface area for abundant active sites. In addition, their microstructural properties including disorder degree and existing state of heteroatom sulfur, can be regulated via different synthetic temperatures providing effective nanovoids and bonding sites. Based on the reaction kinetics analysis, the Na-ion storage mechanism of HNCs can be determined as a capacitive-controlled process, which is essential for improving rate performances. This work demonstrates a novel method to develop a hybrid nanostructure hard carbon, and design of an electrochemical storage mechanism for high-performance and high-safety Na-ion batteries. [ABSTRACT FROM AUTHOR]

Organic carboxylates are well‐accepted as low‐cost anodes for sodium‐ion batteries, owing to their abundant natural resources, structural versatility and suitable potentials. In this work, sodium benzene‐1,2,4‐tricarboxylate (Na‐1,2,4‐BTC), featured as an asymmetric carboxylic‐based coordination salt, is studied as a Na storage anode. The sodium ions exhibit diffusion‐controlled behavior involving the enolization of the C=O groups in Na‐1,2,4‐BTC. Meanwhile, benefiting from its robust organic‐metal coordination framework and fast charge transfer properties, the as‐prepared Na‐1,2,4‐BTC delivers a high initial desodiation capacity of 258 mA h g−1, outstanding rate capability at 2 A g−1 and remarkable cyclability over 500 cycles, demonstrating a great potential as Na‐organic battery anode with high performance and low cost. [ABSTRACT FROM AUTHOR]

This experiment was conducted to evaluate the effects of astragalus polysaccharides (Aps) and ginseng polysaccharide (Gps) on growth performance, liver function, immune function, TLR4 signalling pathways and intestinal barrier in weaned piglets challenged with lipopolysaccharide (LPS). In an experiment spanning 28 days, 180 weaned piglets were randomly divided into three treatment groups: basal diet (Con), basal diet supplemented with 800 mg/kg Gps (Gps) and basal diet supplemented with 800 mg/kg Aps (Aps). At the end of the experiment, 12 piglets of each group were selected; half (n = 6) were intraperitoneally injected with LPS and half with normal saline. Dietary supplementation with Aps and Gps significantly increased (p <.05) the average daily gain and feed conversion rate. Lipopolysaccharide challenge increased (p <.05) expression of serum urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin‐1β (IL‐1β) and tumour inflammatory factor‐α (TNF‐α), but decreased (p <.05) serum superoxide dismutase (SOD) level, total antioxidant capacity (T‐AOC) and immunoglobulin A (IgA) expression. Lipopolysaccharide‐challenged piglets fed with Aps or Gps had lower (p <.05) BUN, ALT, AST, IL‐1β and TNF‐α levels and greater (p <.05) SOD, T‐AOC and IgA levels. Lipopolysaccharide challenge increased (p <.05) the expression of TLR4, MyD88 and NF‐κB, and LPS‐challenged piglets fed diets supplemented with Aps or Gps increased TLR4 and MyD88 and decreased NF‐κB expression. Lipopolysaccharide challenge reduced (p <.05) the jejunal villus height, and piglets fed with Aps or Gps had increased (p <.05) jejunal villus height. Supplementation with Aps or Gps enhanced the expression of occludin and claudin in challenged or unchallenged piglets. In conclusion, dietary supplementation with Aps or Gps enhanced piglet growth performance, alleviated liver dysfunction and reduced immunological stress caused by LPS, as well as increased the intestinal barrier function. [ABSTRACT FROM AUTHOR]

The insulation of S/Li2S and highly soluble nature of polysulfides largely limit the practical use of Li–S batteries. To overcome these issues, tremendous effort has been made for exploring efficient host materials and new battery construction. Herein, we propose to prepare high conductivity Ti2O by a molten salt electrochemical synthesis method; the synthesized Ti2O is developed to serve as an advanced host and used as a functional separator modification material for the first time. XPS analysis and DFT calculations verified that Ti2O can chemically anchor polysulfides through the abundant surface vacancies, and its high electronic conductivity can further enhance the redox kinetics of intermediate polysulfides. The cells based on the Ti2O–Super P/S cathode exhibit a high sulfur utilization and superb rate capability (553 mA h g−1 at 4C). Moreover, the cells assembled with a host-interlayer integrated electrode (2.5 mg cm−2) could achieve a low decay rate of 0.04% over 500 cycles at 0.5C. A high areal capacity of 6.8 mA h cm−2 can be also achieved even under 7.5 mg cm−2 sulfur loading. Overall, the controllable synthesis and application strategies of Ti2O present a way of regulation and optimization of the electrochemical performance of a Ti-based sulfur host through surface vacancy engineering for advanced Li–S batteries. [ABSTRACT FROM AUTHOR]

First-principle calculations within many-body perturbation theory are carried out to investigate the influence of the adsorbed molecules and sulfur (S) defects on the electronic and optical properties of the MoS2 monolayer. The exciton binding energy in the range of 0.05 eV to 1.14 eV is observed as a function of molecular coverage, when NO and 1,3,5-triazin (C3H3N3) are adsorbed on the pristine surface. These results can be explained by the interaction between the exciton and the adsorbed molecule. Furthermore, the combined effect of molecular functionalization and defective doping is studied. Our results show that both the electronic and optical band gaps of the MoS2 monolayer strongly depend on the molecular species and the defective coverage, and can be tuned up to ∼2 eV. This work demonstrates the great potential of controlling the MoS2 monolayer's excitonic properties by molecular functionalization and defective engineering. [ABSTRACT FROM AUTHOR]

The most critical obstacle preventing lithium–sulfur batteries (LSBs) from practical application is the shuttle effect. Herein, we present a zirconium based metal–organic framework (MOF) composite separator which effectively blocks polysulfides from shuttling without hampering the migration of lithium ions owing to the sieving effect of the MOFs. Moreover, owing to the high Brunauer–Emmett–Teller (BET) surface area of 1418 m2 g−1 and chemical interactions with zirconium and oxygen on the MOFs, the polysulfides can also be physically and chemically adsorbed on the surface of the MOFs, which further blocks the polysulfides from shuttling through the intergranular channels of the MOF particles. In addition, the wettability of the composite separator with the electrolyte is enhanced owing to the polar functional groups of –COOH and –OH on the MOFs. The battery with a composite separator delivers an initial discharge capacity of 1239 mA h g−1 at 0.2C and 1147.4 mA h g−1 at 0.5C. The reversible capacity is maintained at 964.1 mA h g−1 with an average fading of only 0.08% per cycle at 0.5C. The capacity at the 2C rate with the composite separator is 955.8 mA h g−1, which is far more than that of the pristine separator, which is 289.2 mA h g−1. [ABSTRACT FROM AUTHOR]

2D carbon nanosheets are considered to be promising candidates for use as sodium ion battery (SIB) anodes due to their large specific surface area and excellent electronic conductivity. However, their applications are hampered by inferior cycling performance, insufficient storage capacity, and high cost. N, B co‐doping carbon nanosheets (NBTs) are synthesized using biomass‐based gelatin as carbon precursor and boric acid as template, and demonstrate their great potential as high‐performance SIB anodes in practical applications. The synergistic effect of heteroatom doping and ultrathin 2D structure provides the NBTs with abundant defects, active sites, and short ion/electron transfer distance, which favors and improves the storage capabilities and rate performances. The optimized NBTs present a remarkable cyclability and superb rate capability (309 mAh g−1 at 0.2 A g−1 for 200 cycles; 225 mAh g−1 at 1 A g−1 for 2000 cycles). Meanwhile, the Na storage mechanism is proved to be a pseudocapacitive‐controlled process, which accounts for the fast charge/discharge behaviors. This work demonstrates an effective template method to produce 2D heteroatoms co‐doping carbon nanosheets to achieve excellent Na storage performances. [ABSTRACT FROM AUTHOR]

A simple method was applied to control the morphology of LiMn2O4 and Li1.05Mn1.97Nb0.03O4 in the sintering process by premixing a suitable proportion of acetylene black in the raw material. Both specific discharge capacity and cycling stability of the samples were improved. The results demonstrated that the doped samples showed excellent electrochemical performance at both 25 °C and 55 °C. [ABSTRACT FROM AUTHOR]

Sodium manganese hexacyanoferrate (NaxMnFe(CN)6) is one of the most promising cathode materials for sodium‐ion batteries (SIBs) due to the high voltage and low cost. However, its cycling performance is limited by the multiple phase transitions during Na+ insertion/extraction. In this work, a facile strategy is developed to synthesize cubic and monoclinic structured NaxMnFe(CN)6, and their structure evolutions are investigated through in situ X‐ray diffraction (XRD), ex situ Raman, and X‐ray photoelectron spectroscopy (XPS) characterizations. It is revealed that the monoclinic phase undergoes undesirable multiple two‐phase reactions (monoclinic ↔ cubic ↔ tetragonal) due to the large lattice distortions caused by the Jahn–Teller effects of Mn3+, resulting in poor cycling performances with 38% capacity retention. The cubic NaxMnFe(CN)6 with high structural symmetry maintains the structural stability during the repeated Na+ insertion/extraction process, demonstrating impressive electrochemical performances with specific capacity of ≈120 mAh g−1 at 3.5 V (vs Na/Na+), capacity retention of ≈70% over 500 cycles at 200 mA g−1. In addition, the TiO2//C‐MnHCF full battery is fabricated with an energy density of 111 Wh kg−1, suggesting the great potential of cubic NaxMnFe(CN)6 for practical energy storage applications. [ABSTRACT FROM AUTHOR]

Herein, a high energy efficiency and long life aqueous Zn–I2 battery based on an activated carbon encapsulated I2 (I2@C-50) cathode is reported. It is found that an optimized electrolyte of Zn(CF3SO3)2 can significantly boost the initial coulombic efficiency from 61.1% to 91.3% due to the coordination effect, which accounts for the high energy efficiency of the battery. Moreover, the in situ formed solid electrolyte interphase (SEI) film on the Zn surface can effectively stabilize Zn stripping/plating and ensure the long-term cycling stability of the aqueous Zn–I2 battery. Besides, an activated carbon host with a large surface area, strong adsorption and spatial confinement suppresses the loss of active materials. As a result, the I2@C-50 cathode realizes a capacity of 210 mA h g−1 and a high energy efficiency of 96.7% at 0.1 A g−1, and exhibits a capacity retention of 66% after 10 000 cycles at 5 A g−1. In addition, pouch batteries with different sizes also demonstrate feasibility in practical applications. The results presented in this work provide insights on electrode, electrolyte and interface engineering to design high performance aqueous batteries. [ABSTRACT FROM AUTHOR]

Enhanced phosphorus (7.2 wt%) and sulfur (15.7 wt%) co-doped carbon (PSC) is synthesized via a one-step sintering of carbon disulfide and red phosphorus in a vacuum. It is found that S atoms can act as immobilization sites for phosphorus by covalently bonding with P atoms in the form of C–S–P, and thus high-level doping of phosphorus can be realized. Owing to the high-level doping, this co-doped carbon shows enlarged interlayer spacing, improved charge transfer capability and strong adsorption of Na+ ions. When tested as an anode for sodium ion batteries, this PSC delivers a high reversible capacity of 513.8 mA h g−1 at 100 mA g−1, excellent rate capability of 181.8 mA h g−1 at 10 A g−1 and superior cycling stability with a capacity of 290.1 mA h g−1 after 1000 cycles at 1 A g−1. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effects of Clostridium butyricum and Enterococcus faecalis on growth performance, immune function, inflammation-related pathways, and microflora community in weaned piglets challenged with lipopolysaccharide (LPS). One hundred and eighty 28-d-old weaned piglets were randomly divided into 3 treatments groups: piglets fed with a basal diet (Con), piglets fed with a basal diet containing 6 × 109 CFU C. butyricum·kg−1 (CB), and piglets fed with a basal diet containing 2 × 1010 CFU E. faecali·kg−1 (EF). At the end of trial, 1 pig was randomly selected from for each pen (6 pigs per treatment group) and these 18 piglets were orally challenged with LPS 25 μg·kg−1 body weight. The result showed that piglets fed C. butyricum and E. faecalis had greater final BW compared with the control piglets (P < 0.05). The C. butyricum and E. faecalis fed piglets had lower levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), IL-1β, tumor inflammatory factor-α (TNF-α), and had greater level of serum interferon-γ (IFN-γ) than control piglets at 1.5 and 3 h after injection with LPS (P < 0.05). Furthermore, piglets in the C. butyricum or E. faecalis treatment groups had a greater ratio of jejunal villus height to crypt depth (V/C) compared with control piglets after challenge with LPS for 3 h (P < 0.05). Compared with the control treatment, the CB and EF treatments significantly decreased the expression of inflammation-related pathway factors (TLR4, MyD88, and NF-κB) after challenge with LPS for 3 h (P < 0.05). High-throughput sequencing revealed that C. butyricum and E. faecalis modulated bacterial diversity in the colon. The species richness and alpha diversity (Shannon) of bacterial samples in CB or EF piglets challenged with LPS were higher than those in LPS-challenged control piglets. Furthermore, the relative abundance of Bacteroidales-Rikenellanceae in the CB group was higher than that in the control group (P < 0.05), whereas EF piglets had a higher relative abundance of Lactobacillus amylovorus and Lactobacillus gasseri (P < 0.05). In conclusion, dietary supplementation with C. butyricum or E. faecalis promoted growth performance, improved immunity, relieved intestinal villus damage and inflammation, and optimized the intestinal flora in LPS-challenged weaned piglets. [ABSTRACT FROM AUTHOR]

The diversity and structure of fungal and bacterial communities in Qupi and Quxin of medium temperature Daqu from one wine corporation located in He'nan were analyzed based on the high-throughput sequencing technology. The results showed that; 1) The diversity and abundance of fungal community in Qupi were higher than those in Quxin samples,and Ascomycetes was the only dominant fungi detected both in Qupi and Quxin. A total of 15 species of fungi was detected in Daqu, of which Saccharomycoosis fibuligera, Eurotium niveoglaucum, Pichia spl were the dominant fungi in Qupi and Quxin samples. Among them, the content of Saccharomvcopsg fibuligera in Qupi was similar to that in Quxin, however, the contents of Eurotium niveoglau cum and Pichia sp1 in Qupi and Quxin samples were quite different. 2) The diversity of bacterial community in Quxin of medium temperature Daqu was higher than that of Qupi, but its abundance was lower than that of Qupi. A total of 28 genera was detected in the Qupi and Quxin samples, of which Enterobacter, Lactobacillus, Lactococcus, Brucella, Enterococcus and Erwinia were dominant bacteria of Daqu samples. Expect for Brucella, the content of other dominant bacteria had a large difference in Qupi and Quxin. [ABSTRACT FROM AUTHOR]

Polydiaminoanthraquinones, featured as redox-active quinone segments linked by polyaniline, were investigated as novel organic cathodes for K-ion batteries. With electron-withdrawing groups (CN) substituted, elevations of the redox potential and capacity utilization were achieved. [ABSTRACT FROM AUTHOR]

Hard carbon is one of the most promising anode materials for sodium ion batteries (SIBs) due to its low cost, high conductivity and suitable potential; however, its application is hindered by its relatively low capacity, and unsatisfactory rate capability and cyclability. Herein, we have reported a high performance SIB anode of S-doped interconnected carbon nanofibers (denoted as S-CNFs) that was directly derived from the industrial waste product bacterial cellulose, demonstrating great potential for practical application and sustainable development. The S-CNFs present high reversible capacities of 460 mA h g−1 at 0.05 A g−1 and 255 mA h g−1 at 10 A g−1, and preserved a capacity of 310 mA h g−1 at 1 A g−1 after 1100 cycles. Structural and electrochemical analyses revealed that multiple factors including the expanded (002) interlayer spacing, the electrochemically active –C–S–C– covalent bonds, the capacitive process induced by a large surface area and considerable defects as well as the stable structure associated with the cross-linked network contributed to their excellent performance. Furthermore, the first principles evaluations confirmed the sodium-storage mechanism of sulfur doping, which not only improved the interlayer distance for the mobility of Na+ but also promoted the electronegativity as well as the electrochemical activity and increased the adsorption of Na+. [ABSTRACT FROM AUTHOR]

Due to their high theoretical energy density, lithium sulfur (Li−S) batteries are promising candidates for next generation energy storage systems. Unfortunately, polysulfide dissolution in ether‐based electrolytes is still a major problem of Li−S batteries. Sulfurized polyacrylonitrile (SPAN) can be used as electrode material in carbonate‐based electrolytes to avoid large‐scale dissolution of polysulfides. But SPAN composites usually suffer from low sulfur content (<50 wt %) and low capacity, limiting their practical application. Here, we synthesize a novel Se doped SPAN (SeSPAN) composite by one‐step thermal treatment. Se atoms are uniformly distributed in the SeSPAN composite and serve as binding sites for S species, increasing the sulfur content up to about 60 wt %, higher than previously reported results. In addition, the Se doping itself is contributing to an increased capacity. The discharge/charge mechanism of the SeSPAN composite is investigate by Raman and X‐ray photoelectron spectroscopy, indicating the existence of Se−S bonds and good electrochemical reversibility. Thus, the SeSPAN cathode delivers an excellent initial specific capacity of 1044 mA h g−1 (calculated for the mass of the whole composite) and a high coulombic efficiency of almost 100 %. Compared with conventional SPAN composites, our SeSPAN material shows a great improvement on the capacity and cycle life and provides a new way to build high capacity SPAN composites. Se is introduced into sulfurized polyacrylonitrile to form a SeSPAN composite as cathode material for lithium‐sulfur batteries. Se serves as binding site to restrain more sulfur species via Se−S bonds, increasing the sulfur content of SeSPAN to 60 wt %. Attributed to the uniformly distributed Se atoms, the novel SeSPAN composite reveals a high capacity of 838 mA h g−1 and stable cycle life over 250 cycles. [ABSTRACT FROM AUTHOR]

Pyrite (FeS2) is considered an attractive Na-storage anode owing to its abundance, environment friendliness and high theoretical capacity (894 mA h g−1). However, it still remains great challenges to realize an applicable FeS2 electrode with both high reversible capacity and long cycle life. In this study, micron-sized FeS2@C composed of FeS2 nanoparticles uniformly embedded in carbon matrix was investigated as a conversion-type anode for sodium ion batteries by coupling with various electrolytes. It is demonstrated that the electrolyte formulations, i.e., both solvents and Na salts, play vital roles in the Na storage performance of FeS2. The combination of NaPF6 and DME was highly advantageous for constructing robust SEI films with high Na+ conductivity, guaranteeing fast and reversible conversion reactions in the wide electrochemical window of 0.005–3 V (vs. Na/Na+). Owing to the fast charge transfer kinetics and high chemical compatibility between the electrolyte and electrode, the as-prepared FeS2@C could deliver a high reversible capacity of 853 mA h g−1 at 0.2 A g−1 and 459 mA h g−1 at 40 A g−1, a remarkable initial coulombic efficiency of 84.7% and excellent cycling stability with capacity retention of 83.2% over 1000 cycles. These parameters prove the great potential of FeS2@C in fulfiling commercial demands for wide range of energy storage applications. [ABSTRACT FROM AUTHOR]