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There is no definitive approach for assessing mesenteric ischemia and determining the optimal timing for endovascular intervention in the management of spontaneous isolated dissection of the superior mesenteric artery (SISMAD). A 56-year-old male with acute abdominal pain was diagnosed with SISMAD. After evaluating mesenteric ischemia through mesenteric fractional flow reserve (FFR), FFR was 0.72, and the patient was recommended conservative treatment for SISMAD, which involves fasting, total parenteral nutrition, and anticoagulation. The patient's syndrome was relieved after conservative treatment for 14 days without stent implantation. Over the next 5 years, no recurrence of abdominal pain or worsening of SISMAD was observed in the patient. Assessing the severity of mesenteric ischemia can be done through mesenteric FFR. Upon confirmation of the exclusion of risks related to dilatation or rupture of SISMAD aneurysm, an approach in favor of conservative management for SISMAD may indeed be considered pragmatic when the FFR exceeds 0.72.
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Hydrogen-bonded organic frameworks (HOFs) are outstanding candidates for photocatalytic hydrogen evolution. However, most of reported HOFs suffer from poor stability and photocatalytic activity in the absence of Pt cocatalyst. Herein, a series of metal HOFs (Co2-HOF-X, X=COOMe, Br, tBu and OMe) have been rationally constructed based on dinuclear cobalt complexes, which exhibit exceptional stability in the presence of strong acid (12â M HCl) and strong base (5â M NaOH) for at least 10â days. More impressively, by varying the -X groups of the dinuclear cobalt complexes, the microenvironment of Co2-HOF-X can be modulated, giving rise to obviously different photocatalytic H2 production rates, following the -X group sequence of -COOMe>-Br>-tBu>-OMe. The optimized Co2-HOF-COOMe shows H2 generation rate up to 12.8â mmol g-1 h-1 in the absence of any additional noble-metal photosensitizers and cocatalysts, which is superior to most reported Pt-assisted photocatalytic systems. Experiments and theoretical calculations reveal that the -X groups grafted on Co2-HOF-X possess different electron-withdrawing ability, thus regulating the electronic structures of Co catalytic centres and proton activation barrier for H2 production, and leading to the distinctly different photocatalytic activity.
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The development of low-cost and efficient photocatalysts to achieve water splitting to hydrogen (H2) is highly desirable but remains challenging. Herein, we design and synthesize two porous polymers (Co-Salen-P and Fe-Salen-P) by covalent bonding of salen metal complexes and pyrene chromophores for photocatalytic H2 evolution. The catalytic results demonstrate that the two polymers exhibit excellent catalytic performance for H2 generation in the absence of additional noble-metal photosensitizers and cocatalysts. Particularly, the H2 generation rate of Co-Salen-P reaches as high as 542.5 µmol g-1 h-1, which is not only 6 times higher than that of Fe-Salen-P but also higher than a large amount of reported Pt-assisted photocatalytic systems. Systematic studies show that Co-Salen-P displays faster charge separation and transfer efficiencies, thereby accounting for the significantly improved photocatalytic activity. This study provides a facile and efficient way to fabricate high-performance photocatalysts for H2 production.
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In order to simultaneously accelerate ion and electron transfer in sodium-ion battery (SIB) cathodes, a topotactic superlattice was utilized, in which the atomically intrinsic lattice-matching effect from inner to external surface can boost the charge transfer due to the disappearance of the heterojunction interface. Herein, a topotactic syntopogenous Na3VF6/NaVF3 superlattice formulated as Na2.9V1.1F6 (NVF) was synthesized by a facile one-step low-temperature hydrothermal reaction. NVF nanoparticles show an excellent Na+ storage capacity (â¼205 mAh g-1) in a high voltage window up to 4.2 V with ultralong cycling stability. That is associated with the mixed occupancy of V and Na in NVF. The multivalent V centers serve as electron reservoirs to inhibit phase transformation, and the Na-enriched Na3VF6 with better electron conductivity acts as a Na+ reservoir for effective electron transfer. Highly reversible (de)intercalation of Na+ is achieved in the channel of perovskite-type NaVF3 with structural integrity.
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Dinuclear metal synergistic catalysis (DMSC) has been proved an effective approach to enhance catalytic efficiency in photocatalytic CO2 reduction reaction, while it remains challenge to design dinuclear metal complexes that can show DMSC effect. The main reason is that the influence of the microenvironment around dinuclear metal centres on catalytic activity has not been well recognized and revealed. Herein, we report a dinuclear cobalt complex featuring a planar structure, which displays outstanding catalytic efficiency for photochemical CO2-to-CO conversion. The turnover number (TON) and turnover frequency (TOF) values reach as high as 14457 and 0.40 s-1 respectively, 8.6 times higher than those of the corresponding mononuclear cobalt complex. Control experiments and DFT calculations revealed that the enhanced catalytic efficiency of the dinuclear cobalt complex is due to the indirect DMSC effect between two CoII ions, energetically feasible one step two-electron transfer process by Co2I,I intermediate to afford Co2II,II(CO22-) intermediate and fast mass transfer closely related with the planar structure.
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Aging significantly elevates the risk for Alzheimer's disease (AD), contributing to the accumulation of AD pathologies, such as amyloid-ß (Aß), inflammation, and oxidative stress. The human prefrontal cortex (PFC) is highly vulnerable to the impacts of both aging and AD. Unveiling and understanding the molecular alterations in PFC associated with normal aging (NA) and AD is essential for elucidating the mechanisms of AD progression and developing novel therapeutics for this devastating disease. In this study, for the first time, we employed a cutting-edge spatial transcriptome platform, STOmics® SpaTial Enhanced Resolution Omics-sequencing (Stereo-seq), to generate the first comprehensive, subcellular resolution spatial transcriptome atlas of the human PFC from six AD cases at various neuropathological stages and six age, sex, and ethnicity matched controls. Our analyses revealed distinct transcriptional alterations across six neocortex layers, highlighted the AD-associated disruptions in laminar architecture, and identified changes in layer-to-layer interactions as AD progresses. Further, throughout the progression from NA to various stages of AD, we discovered specific genes that were significantly upregulated in neurons experiencing high stress and in nearby non-neuronal cells, compared to cells distant from the source of stress. Notably, the cell-cell interactions between the neurons under the high stress and adjacent glial cells that promote Aß clearance and neuroprotection were diminished in AD in response to stressors compared to NA. Through cell-type specific gene co-expression analysis, we identified three modules in excitatory and inhibitory neurons associated with neuronal protection, protein dephosphorylation, and negative regulation of Aß plaque formation. These modules negatively correlated with AD progression, indicating a reduced capacity for toxic substance clearance in AD subject samples. Moreover, we have discovered a novel transcription factor, ZNF460, that regulates all three modules, establishing it as a potential new therapeutic target for AD. Overall, utilizing the latest spatial transcriptome platform, our study developed the first transcriptome-wide atlas with subcellular resolution for assessing the molecular alterations in the human PFC due to AD. This atlas sheds light on the potential mechanisms underlying the progression from NA to AD.
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INTRODUCTION: Traditionally associated with undernutrition, increasing evidence suggests micronutrient deficiencies can coexist with overnutrition. Therefore, this work aimed to systematically review the associations between iron, zinc and vitamin A (VA) status and weight status (both underweight and overweight) in children and young people. METHODS: Ovid Medline, Ovid Embase, Scopus and Cochrane databases were systematically searched for observational studies assessing micronutrient status (blood, serum or plasma levels of iron, zinc or VA biomarkers) and weight status (body mass index or other anthropometric measurement) in humans under 25 years of any ethnicity and gender. Risk of bias assessment was conducted using the American Dietetic Association Quality Criteria Checklist. Where possible, random effects restricted maximum likelihood meta-analyses were performed. RESULTS: After screening, 83 observational studies involving 190 443 participants from 44 countries were identified, with many studies having reported on more than one micronutrient and/or weight status indicator. Iron was the most investigated micronutrient, with 46, 28 and 27 studies reporting data for iron, zinc and VA status, respectively. Synthesising 16 records of OR from seven eligible studies, overnutrition (overweight and obesity) increased odds of iron deficiency (ID) (OR (95% CI): 1.51 (1.20 to 1.82), p<0.0001, I2=40.7%). Odds appeared to be higher for children living with obesity (1.88 (1.33 to 2.43), p<0.0001, I2=20.6%) in comparison to those with overweight (1.31 (0.98 to 1.64), p<0.0001, I2=40.5%), although between group differences were not significant (p=0.08). CONCLUSIONS: Overnutrition is associated with increased risk of ID, but not zinc or VA deficiencies, with an inverted U-shaped relationship observed between iron status and bodyweight. Our results highlight significant heterogeneity in the reporting of micronutrient biomarkers and how deficiencies were defined. Inflammation status was rarely adequately accounted for, and the burden of ID may well be under-recognised, particularly in children and young people living with overnutrition. PROSPERO REGISTRATION NUMBER: CRD42020221523.
Subject(s)
Overnutrition , Vitamin A Deficiency , Zinc , Humans , Zinc/deficiency , Zinc/blood , Child , Vitamin A Deficiency/blood , Risk Factors , Adolescent , Iron Deficiencies , Child, Preschool , Young Adult , Male , Female , Nutritional Status , Vitamin A/blood , Iron/bloodABSTRACT
BACKGROUND: Pathogenesis and diagnostic biomarkers of aortic dissection (AD) can be categorized through the analysis of differential metabolites in serum. Analysis of differential metabolites in serum provides new methods for exploring the early diagnosis and treatment of aortic dissection. OBJECTIVES: This study examined affected metabolic pathways to assess the diagnostic value of metabolomics biomarkers in clients with AD. METHOD: The serum from 30 patients with AD and 30 healthy people was collected. The most diagnostic metabolite markers were determined using metabolomic analysis and related metabolic pathways were explored. RESULTS: In total, 71 differential metabolites were identified. The altered metabolic pathways included reduced phospholipid catabolism and four different metabolites considered of most diagnostic value including N2-gamma-glutamylglutamine, PC(phocholines) (20:4(5Z,8Z,11Z,14Z)/15:0), propionyl carnitine, and taurine. These four predictive metabolic biomarkers accurately classified AD patient and healthy control (HC) samples with an area under the curve (AUC) of 0.9875. Based on the value of the four different metabolites, a formula was created to calculate the risk of aortic dissection. Risk score = (N2-gamma-glutamylglutamine × -0.684) + (PC (20:4(5Z,8Z,11Z,14Z)/15:0) × 0.427) + (propionyl carnitine × 0.523) + (taurine × -1.242). An additional metabolic pathways model related to aortic dissection was explored. CONCLUSION: Metabolomics can assist in investigating the metabolic disorders associated with AD and facilitate a more in-depth search for potential metabolic biomarkers.
Subject(s)
Aortic Aneurysm , Aortic Dissection , Biomarkers , Metabolomics , Predictive Value of Tests , Humans , Aortic Dissection/blood , Aortic Dissection/diagnosis , Male , Biomarkers/blood , Female , Middle Aged , Case-Control Studies , Aortic Aneurysm/blood , Aortic Aneurysm/diagnosis , Aged , Adult , Metabolome , Risk AssessmentABSTRACT
BACKGROUND: Childhood malnutrition in all forms is a major public health issue worldwide. This review systematically examined the prevalence and determinants and identify the potential interventions and current gap in addressing malnutrition including undernutrition, overnutrition and micronutrient deficiencies (MNDs) in Vietnamese children aged 0-18 years old. METHODS: Embase, Scopus, PubMed, and Web of Science were systematically searched through June 2022 to identify relevant articles published within the past 25 years. Study selection and data extraction were performed by one reviewer and checked for accuracy by the other two reviewers in accordance with PRISMA guideline. Risk of publication bias was assessed using American Dietetic Association Quality Criteria Checklist. RESULTS: Seventy-two studies that met the inclusion criteria were included. Undernutrition has decreased over time but still 22.4%, 5.2% and 12.2% of children under 5 were stunted, wasted and underweight, respectively. Anaemia, iron, zinc, and vitamin D deficiencies were the more common forms of MNDs, the prevalence varied by age, region, and socioeconomic group. Population-based surveys reported that 11% and 48% of children aged 0-11 years old were iron and vitamin D deficient, respectively. Zinc deficiency affected almost one-quarter of the children and adolescents. Retinol deficiency was of less concern (< 20%). However, more evidence on MNDs prevalence is needed. Overweight and obesity is now on the rise, affecting one-third of school-aged children. The key determinants of undernutrition included living in rural areas, children with low birth weight, and poor socio-economic status, whereas living in urban and affluent areas, having an inactive lifestyle and being a boy were associated with increased risk of overweight and obesity. Nutrition specific intervention studies including supplementation and food fortification consistently showed improvements in anthropometric indices and micronutrient biomarkers. National nutrition-sensitive programmes also provided nutritional benefits for children's growth and eating behaviours, but there is a lack of data on childhood obesity. CONCLUSION: This finding highlights the need for effective double duty actions to simultaneously address different forms of childhood malnutrition in Vietnam. However, evidence on the potential intervention strategies, especially on MNDs and overnutrition are still limited to inform policy decision, thus future research is warranted.
Subject(s)
Malnutrition , Overnutrition , Adolescent , Child , Child, Preschool , Humans , Infant , Infant, Newborn , Iron , Malnutrition/epidemiology , Malnutrition/complications , Micronutrients , Nutritional Status , Overnutrition/complications , Overnutrition/epidemiology , Overweight/epidemiology , Pediatric Obesity/epidemiology , Prevalence , Vietnam/epidemiology , ZincABSTRACT
Na metal batteries using inorganic solid-state electrolytes (SSEs) have attracted extensive attention due to their superior safety and high energy density. However, their development is plagued by the unclear structural/volumetric evolution of SSEs and the corresponding Na+ migration mechanisms. In this work, NaSn2F5 (NSF) clusters are composed of nanoparticles (NPs) with matched lattices induced by dislocations, which can mitigate the volume swelling/shrinkage of the NPs. NSF behaves like a single ion conductor with a high Na+ transference number (tNa+) of 0.79. Specially, the ionic conductivity (σ) of NSF is increased from 7.64 × 10-6 to 5.42 × 10-5 S cm-1 after partial irreversible oxidation of Sn2+ (0.118 Å) â Sn4+ (0.069 Å) with the shrunk ionic radius during the charge process, giving more spaces for Na+ migration. Furthermore, a poly(acrylonitrile)-NaSn2F5-NaPF6 composite polymer electrolyte (NSF CPE) was fabricated with a σ of 4.13 × 10-4 S cm-1 and a tNa+ of 0.60. The NSF CPE-based symmetric cell can operate over 3000 h due to the couplings between the different components in NSF CPE, which is beneficial for ion transfer and the construction of stable solid electrolyte interface. And the quasi-solid-state Na|NSF CPE|Na3V2(PO4)3 full cell displays excellent electrochemical performance.
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Fuke Qianjin capsules (FKQJ) exhibit obvious advantages and characteristics in the treatment of pelvic inflammatory disease. At present, information regarding the in vivo process of FKQJ is lacking, which has become a bottleneck in further determining the therapeutic effect of this traditional Chinese medicine. In the present study, a sensitive, simple and reliable method was developed and validated for the simultaneous quantification of 12 main components (4 flavonoids, 4 alkaloids, 2 phthalides and 2 diterpene lactones) in plasma and seven tissues of rats to study the pharmacokinetic and distribution characteristics of these components in vivo by using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the first time. Plasma and tissue were prepared by protein precipitation with acetonitrile and methanol, followed by its separation on a Waters Acquity UPLC BEH C18 column. The quantification was performed via multiple reaction monitoring (MRM) by a triple quadrupole mass spectrometer under positive electrospray ionization (ESI) mode. The method was validated to demonstrate its selectivity, linearity, accuracy, precision, recovery, matrix effect and stability. For 12 analytes, the low limit of quantification (LLOQs) reached 0.005-2.44â¯ng/mL, and all calibration curves showed good linearity (r2 ≥ 0.990) in linear ranges. The intra-day and inter-day precision (relative standard deviation) for all analytes was less than 14.96%, and the accuracies were in the range of 85.29%-114.97%. Extraction recoveries and matrix effects of analytes were acceptable. The pharmacokinetic results showed that the main components could be absorbed quickly, had a short residence time, and were eliminated quickly in vivo. At different time points, the 12 components were widely distributed with uneven characteristics in the body, which tended to be distributed in the liver, kidney and lung and to a lesser extent in the uterus, brain and heart. The pharmacokinetic process and tissue distribution characteristics of FKQJ were expounded in this study, which can provide a scientific theory for in-depth development of FKQJ and guide FKQJ use in the clinic.
Subject(s)
Drugs, Chinese Herbal , Female , Rats , Animals , Chromatography, Liquid/methods , Chromatography, High Pressure Liquid/methods , Drugs, Chinese Herbal/analysis , Tandem Mass Spectrometry/methods , Tissue Distribution , Reproducibility of ResultsABSTRACT
Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins widely distributed in maize and maized-based products, often occurring together. The implications of co-exposure to aflatoxin and fumonsin for human health are numerous, but a particular concern is the potential of FB1 to modulate AFB1 hepatotoxicity. This study evaluated the toxicity of these mycotoxins, alone or combined, in a human non-tumorigenic liver cell line, HHL-16 cells, and assessed the effects of AFB1 and FB1 on expression of genes involved in immune and growth factor pathways. The results demonstrated that in HHL-16 cells, both AFB1 and FB1 had dose-dependent and time-dependent toxicity, and the combination of them showed a synergistic toxicity in the cells. Moreover, AFB1 caused upregulation of IL6, CCL20, and BMP2, and downregulation of NDP. In combination of AFB1 with FB1, gene expression levels of IL6 and BMP2 were significantly higher compared to individual FB1 treatment, and had a tendency to be higher than individual AFB1 treatment. This study shows that FB1 may increase the hepatoxicity of AFB1 through increasing the inflammatory response and disrupting cell growth pathways.
Subject(s)
Aflatoxin B1 , Fumonisins , Hepatocytes , Fumonisins/toxicity , Humans , Hepatocytes/drug effects , Hepatocytes/metabolism , Aflatoxin B1/toxicity , Cell Line , Inflammation/genetics , Inflammation/chemically induced , Gene Expression Regulation/drug effects , Intercellular Signaling Peptides and Proteins/genetics , Intercellular Signaling Peptides and Proteins/metabolism , Interleukin-6/genetics , Interleukin-6/metabolism , Bone Morphogenetic Protein 2/genetics , Bone Morphogenetic Protein 2/metabolismABSTRACT
Accurate prognosis for cancer patients can provide critical information for optimizing treatment plans and improving life quality. Combining omics data and demographic/clinical information can offer a more comprehensive view of cancer prognosis than using omics or clinical data alone and can also reveal the underlying disease mechanisms at the molecular level. In this study, we developed and validated a deep learning framework to extract information from high-dimensional gene expression and miRNA expression data and conduct prognosis prediction for breast cancer and ovarian-cancer patients using multiple independent multi-omics datasets. Our model achieved significantly better prognosis prediction than the current machine learning and deep learning approaches in various settings. Moreover, an interpretation method was applied to tackle the "black-box" nature of deep neural networks and we identified features (i.e., genes, miRNA, demographic/clinical variables) that were important to distinguish predicted high- and low-risk patients. The significance of the identified features was partially supported by previous studies.
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Background: The global burden of liver cirrhosis is increasing, with 2.1 million incident cases and nearly 1.5 million deaths in 2019. Despite the enormous progress in our understanding of the etiology of liver cirrhosis, significant cases of the disease have been reported in Eastern Ethiopia due to unidentified causes. Hence, this study aimed to identify predictors of liver cirrhosis of unknown etiology in Eastern Ethiopia. Methods: A score of 7 out of 11 possible points on the ultrasound-based cirrhosis scale was used as a diagnostic criterion to include 127 liver cirrhosis patients. The study participants' demographic, dietary, lifestyle, and clinical data were gathered using a structured questionnaire and standardized reporting forms. The associations between the outcome (known and unknown etiology) and independent variables were modeled using binary logistic regression analysis. Results: The etiology of liver cirrhosis was known in only 23% of patients and attributed to hepatitis B virus (21%), hepatitis C virus (0.8%), and alcohol abuse (0.8%). Sorghum consumption as a staple food (adjusted odds ratio (AOR) =3.8; 95% CI: 1.2, 12.5), splenomegaly (AOR = 4.0; 95% CI: 1.1, 14.4), and a family history of liver disease (AOR = 0.24; 95% CI: 0.06, 0.91) were significantly associated with liver cirrhosis of unknown etiology. Conclusion: Sorghum consumption was found to be the determinant factor of liver cirrhosis of unknown etiology, suggesting it as a possible source of exposure to aflatoxin B1.
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Aqueous zinc-ion hybrid supercapacitors (ZHSCs) with the characteristics of low cost, long cycle stability, and good safety have been regarded as potential candidates for wearable energy storage applications. Herein, we reasonably designed a unique binder-free nitrogen-doped (N-doped) porous carbon@TiO2@Ti multilayer core-sheath wire (N-CTNT), which has vertical N-doped carbon nanoholes radially aligned on the wire surface. The unique structure and nitrogen dopants of N-CTNTs have facilitated zinc deposition on N-CTNT to form a hierarchical and robust zinc-carbon composite (Zn@N-CTNTs). A wire-shaped ZHSC was constructed with N-CTNTs and Zn@N-CTNTs as cathode and anode electrodes, respectively. The as-prepared ZHSC has an outstanding specific capacitance of 488 mF cm-2 at 1 mA cm-2. This hybrid supercapacitor also exhibits an excellent energy density of 211 µW h cm-2, good rate performance, and long cycle stability with a capacity retention rate of 90.4% after 16,000 cycles.
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Covalent organic frameworks (COFs) have been widely studied in photocatalytic CO2 reduction reaction (CO2 RR). However, pristine COFs usually exhibit low catalytic efficiency owing to the fast recombination of photogenerated electrons and holes. In this study, we fabricated a stable COF-based composite (GO-COF-366-Co) by covalently anchoring COF-366-Co on the surface of graphene oxide (GO) for the photocatalytic CO2 reduction. Interestingly, in absolute acetonitrile (CH3 CN), GO-COF-366-Co shows a high selectivity of 94.4 % for the photoreduction of CO2 to formate, with a formate yield of 15.8â mmol/g, which is approximately four times higher than that using the pristine COF-366-Co. By contrast, in CH3 CN/H2 O (v : v=4 : 1), the main product for the photocatalytic CO2 reduction over GO-COF-366-Co is CO (96.1 %), with a CO yield as high as 52.2â mmol/g, which is also approximately four times higher than that using the pristine COF-366-Co. Photoelectrochemical experiments demonstrate the covalent bonding of COF-366-Co and GO to form the GO-COF-366-Co composite facilitates charge separation and transfer significantly, thereby accounting for the enhanced catalytic activity. In addition, theoretical calculations and in situ Fourier transform infrared spectroscopy reveal H2 O can stabilize the *COOH intermediate to further form a *CO intermediate via O-H(aq)â â â O(*COOH) hydrogen bonding, thus explaining the regulated photocatalytic performance.
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The adsorption of aflatoxin B1 (AFB1) to natural fiber materials prepared from corn by-products was investigated in this study. The results showed that corn cob powder (CCP) dose, particle size, time (0.25-24 h), temperature (4, 20, 37, 50 and 100 °C) and pH (2-8), had significant effects on adsorption. The maximum adsorption (98%) was with particles 500-355 µm in size at 20 °C for 8 h, at the dose of 50 mg mL-1. The adsorption fitted pseudo-second-order model and Langmuir isotherm well. Besides, CCP had a higher adsorption capacity to AFB1 than any single cell wall components of corn, which indicated that capillary effect happened in cell wall might be the main reason for adsorption. The results also suggested that CCP could reduce AFB1 content from both liquid and solid food matrixes. Briefly, CCP displayed promising properties that could be developed in nature-based practical applications for food aflatoxin decontamination.
Subject(s)
Aflatoxin B1 , Aflatoxins , Aflatoxin B1/analysis , Zea mays , Adsorption , Aflatoxins/analysis , TemperatureABSTRACT
Na metal batteries using solid-state electrolytes (SSEs) have attracted intensive attention due to their superior safety and high energy density. However, the interfacial issue is one of the biggest challenges to their working normally for the achievement of high performance. To address the high SSE/Na interfacial resistance and facilitate Na+ migration, an efficient approach based on a lattice-matching effect is proposed. In this work, we synthesized a sheet-like layered sodium titanate with rich oxygen vacancies formulated as Na0.98Ti1.3O3 (NTO). The NTO sheet behaves like a single ion conductor with a low ion migration activation energy of â¼0.159 eV and a high ion transference number (tNa+) of 0.91, which is due to the weak interactions between the lamellar Na+ ions and unmoved anionic Ti-O-Ti layers in NTO. An NTO composite polymer electrolyte (CPE) was fabricated by combination with poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) and NaPF6, and it exhibited a high ion conductivity (σ) of 1.16 × 10-4 S cm-1 with a tNa+ of 0.73. The Na|NTO|Na symmetric cell can work normally in the initial discharge/charge cycles and the Na|NTO CPE|Na cell can endure long-term Na stripping/plating, which is associated with the matched lattice of the Na (110) and NTO (001) facets, d(110) (Na) = d(001) (NTO). Moreover, the Na|NTO CPE|Na3V2(PO4)3 (NVP) full cell presents a high discharge capacity with a good cycling performance. This is probably associated with the intrinsic oxygen vacancies in NTO, which can capture the PF6- anions and accelerate the dissociation of Na+-PF6- pairs in the CPE. And the decreased crystallinity of each component in NTO CPE can promote the migration of Na+ in NTO and along the amorphous PVDF-HFP polymer chain.
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Sodium-ion battery (SIB) is a reasonable alternative to lithium-ion battery (LIB) in the field of grid-scale energy storage systems. Unfortunately, the development of appropriate cathode material is a bottleneck in the field of SIB. In the present work, (p-TQ)-VO, formulated as (p-TQ)0.2V2O5·0.38H2O, was synthesized based on a facile hydrothermal reaction of V2O5 and methylhydroquinone (p-HTQ). And when V2O5 was replaced by VN, (p-TQ)-VN, formulated as (p-TQ)0.22V2(O/N)5, was prepared instead. The (p-TQ)-VO sample displays good electrochemical performance as the SIB cathode. And (p-TQ)-VN shows a much higher capacity at a small current density, and it can maintain structural integrity with partial topotactic phase transformation into NaxV2O5 during the discharge/charge process. A series of characterizations of (p-TQ)-VO and (p-TQ)-VN reveals the successful intercalation of p-TQ into the layered V2O5 with a (001) lattice spacing of 13.7 and 10.7 Å, respectively. In (p-TQ)-VN, partial terminal oxygen (Ot) atoms from the V-O-V layer have been substituted by N atoms, which can boost the orbital hybridization of V 3d and Ot 2p, shorten the V-Ot bonds in the c-axial direction, and elongate the V-O bonds in the ab plane with compressed {VO4N2} octahedra, giving rise to mixed-anion coordination effect. As a result, the enhanced electron densities around the Ot atoms of the V-O-V layer can facilitate the affinity toward the inserted Na+ ions, leading to partial phase conversion into NaNO2/NaNO3. Moreover, density functional density (DFT) calculations reveal that the N-incorporation can improve electron conductivity with richer molecular orbital energy levels, resulting in multistep redox reactions and enhanced capacity.