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1.
Rev Cardiovasc Med ; 25(7): 257, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39139434

ABSTRACT

Atrial fibrillation (AF) is the most prevalent arrhythmia worldwide. Although the guidelines for AF have been updated in recent years, its gradual onset and associated risk of stroke pose challenges for both patients and cardiologists in real-world practice. Artificial intelligence (AI) is a powerful tool in image analysis, data processing, and for establishing models. It has been widely applied in various medical fields, including AF. In this review, we focus on the progress and knowledge gap regarding the use of AI in AF patients and highlight its potential throughout the entire cycle of AF management, from detection to drug treatment. More evidence is needed to demonstrate its ability to improve prognosis through high-quality randomized controlled trials.

2.
Chem Sci ; 15(32): 12879-12888, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39148782

ABSTRACT

Antifluorite-type Li5FeO4 (LFO) belongs to a class of promising prelithiation materials for next-generation high-energy lithium-ion batteries. Unfortunately, the incomplete de-lithiation performance and inferior air stability hinder its application. In this work, ultra-high capacity is achieved by selective doping of Zr into the Fe sites (LFO-Zr) of LFO to form a large number of defects. The underlying defect formation mechanism is comprehensively investigated using density functional theory, revealing that such selective site doping not only enlarges the unit cell volume but also induces Li vacancies into the structure, both of which facilitate lithium-ion migration at a high-rate and promote the redox of oxygen anions. As a result, under 0.05 and 1C rates, the capacity of LFO-Zr reaches 805.7 and 624.5 mA h g-1, which are 69.0 and 262.0 mA h g-1 higher than those of LFO, translating to an increase of 9.4% and 73.3%, respectively. In addition, LFO-Zr exhibits excellent electrochemical performance in a humidity of 20%, with a high capacity of 577.6 mA h g-1 maintained. With the LFO-Zr additive, the full cell delivered 193.6 mA h g-1 for the initial cycle at 0.1C. The defect engineering strategy presented in this work delivers insights to promote ultra-high capacity and high-rate performance of air-stable LFO.

3.
Heliyon ; 10(15): e35218, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39157410

ABSTRACT

Background: Restoring and maintaining sinus rhythm in patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI) has been studied in clinical trials to reduce symptoms and improve quality of life. Limited data exist on the effectiveness of rate or rhythm control therapy in these patients. Methods: Consecutive patients with AF and ACS or referred for PCI were prospectively recruited in Fuwai Hospital during 2017-2020. The primary endpoints were all-cause death and major adverse cardiovascular and cerebrovascular events (MACCEs), including cardiovascular mortality, myocardial infarction, ischemic stroke, non-central nervous system embolism and ischemia-driven revascularization. Kaplan-Meier curves and Cox regressions were performed to evaluate the association between rhythm/rate control and subsequent outcomes. For the primary endpoints, we used the Benjamini-Hochberg correction for multiple comparisons. Results: A total of 1499 patients with AF and ACS or undergoing PCI were included, with a median follow-up of 34.7 months. Compared to non-rate control, rate control strategy reduced the risk of subsequent MACCEs (adjusted HR, 0.320; 95 % CI 0.220-0.466; p <0.001; *p <0.002) and all-cause death (adjusted HR, 0.148; 95 % CI 0.093-0.236; p <0.001; *p <0.002). Similar trends were observed across all predefined subgroups (p <0.001). In the final multivariate model, rhythm control was not associated with a lower subsequent MACCEs but significantly improved all-cause mortality compared to non-rhythm control (adjusted HR, 0.546; 95 % CI 0.313-0.951; p =0.033; *p =0.044). Conclusions: In this real-world study, rate control strategy was associated with lower risk of MACCEs and all-cause death in AF and ACS or undergoing PCI. Besides, management with rhythm control strategy may improve all-cause mortality.

4.
Theranostics ; 14(9): 3565-3582, 2024.
Article in English | MEDLINE | ID: mdl-38948069

ABSTRACT

Cancer therapy has moved from single agents to more mechanism-based targeted approaches. In recent years, the combination of HDAC inhibitors and other anticancer chemicals has produced exciting progress in cancer treatment. Herein, we developed a novel prodrug via the ligation of dichloroacetate to selenium-containing potent HDAC inhibitors. The effect and mechanism of this compound in the treatment of prostate cancer were also studied. Methods: The concerned prodrug SeSA-DCA was designed and synthesized under mild conditions. This compound's preclinical studies, including the pharmacokinetics, cell toxicity, and anti-tumor effect on prostate cancer cell lines, were thoroughly investigated, and its possible synergistic mechanism was also explored and discussed. Results: SeSA-DCA showed good stability in physiological conditions and could be rapidly decomposed into DCA and selenium analog of SAHA (SeSAHA) in the tumor microenvironment. CCK-8 experiments identified that SeSA-DCA could effectively inhibit the proliferation of a variety of tumor cell lines, especially in prostate cancer. In further studies, we found that SeSA-DCA could also inhibit the metastasis of prostate cancer cell lines and promote cell apoptosis. At the animal level, oral administration of SeSA-DCA led to significant tumor regression without obvious toxicity. Moreover, as a bimolecular coupling compound, SeSA-DCA exhibited vastly superior efficacy than the mixture with equimolar SeSAHA and DCA both in vitro and in vivo. Our findings provide an important theoretical basis for clinical prostate cancer treatment. Conclusions: Our in vivo and in vitro results showed that SeSA-DCA is a highly effective anti-tumor compound for PCa. It can effectively induce cell cycle arrest and growth suppression and inhibit the migration and metastasis of PCa cell lines compared with monotherapy. SeSA-DCA's ability to decrease the growth of xenografts is a little better than that of docetaxel without any apparent signs of toxicity. Our findings provide an important theoretical basis for clinical prostate cancer treatment.


Subject(s)
Apoptosis , Cell Cycle Checkpoints , Histone Deacetylase Inhibitors , Prostatic Neoplasms , cdc25 Phosphatases , Male , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Humans , Animals , Apoptosis/drug effects , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylase Inhibitors/therapeutic use , Histone Deacetylase Inhibitors/chemistry , Cell Line, Tumor , Cell Cycle Checkpoints/drug effects , cdc25 Phosphatases/metabolism , Mice , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Mice, Nude , Selenium/pharmacology , Selenium/chemistry , Selenium/therapeutic use , Xenograft Model Antitumor Assays , Prodrugs/pharmacology , Prodrugs/chemistry , Mice, Inbred BALB C
5.
Angew Chem Int Ed Engl ; : e202409719, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39052469

ABSTRACT

Stable solid-electrolyte interphase (SEI) is crucial for cycling reversibility of Na-ion batteries by mitigating continuous side reactions. So far, the severe SEI dissolution leads to low Coulombic efficiency (CE) and short cycle life. Meanwhile, the quantified relationship between SEI components and their solubility remains unclear. In this work, we establish the direct correlation between SEI components and SEI solubility, and quantify that the solubility of organic-rich SEI is 3.26 times of inorganic-rich SEI. We further propose a feasible strategy to preform inorganic-rich insoluble SEI and demonstrate a practical hard carbon (HC)||NaMn0.33Fe0.33Ni0.33O2 full cell in commercial electrolyte of 1 M NaPF6 in propylene carbonate (PC) with 80.0% capacity retention for 900 cycles, and achieve a record-high average CE of 99.95% for a practical Na-ion full cell. This study provides an effective strategy of preforming insoluble SEI to suppress its dissolution towards highly reversible Na-ion batteries.

6.
Chem Sci ; 15(29): 11188-11228, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39055002

ABSTRACT

The oxygen reduction reaction (ORR) is a key component for many clean energy technologies and other industrial processes. However, the low selectivity and the sluggish reaction kinetics of ORR catalysts have hampered the energy conversion efficiency and real application of these new technologies mentioned before. Recently, tremendous efforts have been made in mechanism understanding, electrocatalyst development and system design. Here, a comprehensive and critical review is provided to present the recent advances in the field of the electrocatalytic ORR. The two-electron and four-electron transfer catalytic mechanisms and key evaluation parameters of the ORR are discussed first. Then, the up-to-date synthetic strategies and in situ characterization techniques for ORR electrocatalysts are systematically summarized. Lastly, a brief overview of various renewable energy conversion devices and systems involving the ORR, including fuel cells, metal-air batteries, production of hydrogen peroxide and other chemical synthesis processes, along with some challenges and opportunities, is presented.

7.
Adv Mater ; 36(27): e2403073, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38553938

ABSTRACT

Na-ion batteries (NIBs) are sustainable alternatives to Li-ion technologies due to the abundant and widely-distributed resources. However, the most promising cathode materials of NIBs so far, O3 layered oxides, suffer from serious air instability issues, which significantly increases the manufactural cost and carbon footprint because of the long-term use of dry rooms. While some feasible strategies are proposed via case studies, universal design strategies for air-stable cathodes are yet to be established. Herein, the air degradation mechanisms of O3 cathodes are investigated via combined first-principles and experimental approaches, with bond dissociation energy proposed as an effective descriptor for predicting air stability. Experimental validations in various unary, binary, and ternary O3 cathodes confirm that the air stability can indeed be effectively improved via simple compositional design. Guided by the predictive model, the designed material can sustain 30-day air-storage without structural or electrochemical degradation. It is calculated that such air-stable cathodes can significantly reduce both energy consumption (≈4 100 000 kWh) and carbon footprint (≈2200-ton CO2) annually for a 2 GWh NIBs manufactory. Therefore, the fundamental understandings and universal design strategy presented open an avenue for rational materials design of NIBs toward both elemental and manufactural sustainability.

8.
Biomed Pharmacother ; 173: 116406, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38460366

ABSTRACT

Sanguinarine is a quaternary ammonium benzophenanthine alkaloid found in traditional herbs such as Chelidonium, Corydalis, Sanguinarum, and Borovula. It has been proven to possess broad-spectrum biological activities, such as antitumor, anti-inflammatory, antiosteoporosis, neuroprotective, and antipathogenic microorganism activities. In this paper, recent progress on the biological activity and mechanism of action of sanguinarine and its derivatives over the past ten years is reviewed. The results showed that the biological activities of hematarginine and its derivatives are related mainly to the JAK/STAT, PI3K/Akt/mTOR, NF-κB, TGF-ß, MAPK and Wnt/ß-catenin signaling pathways. The limitations of using sanguinarine in clinical application are also discussed, and the research prospects of this subject are outlined. In general, sanguinarine, a natural medicine, has many pharmacological effects, but its toxicity and safety in clinical application still need to be further studied. This review provides useful information for the development of sanguinarine-based bioactive agents.


Subject(s)
Alkaloids , Phosphatidylinositol 3-Kinases , Phosphatidylinositol 3-Kinases/metabolism , Benzophenanthridines/pharmacology , Alkaloids/metabolism , Isoquinolines/pharmacology
9.
Biosci Trends ; 18(1): 94-104, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38325821

ABSTRACT

This study aimed to investigate the causal role of diabetes mellitus (DM), glycemic traits, and sodium-glucose cotransporter 2 (SGLT2) inhibition in pulmonary arterial hypertension (PAH). Utilizing a two-sample two-step Mendelian randomization (MR) approach, we determined the causal influence of DM and glycemic traits (including insulin resistance, glycated hemoglobin, and fasting insulin and glucose) on the risk of PAH. Moreover, we examined the causal effects of SGLT2 inhibition on the risk of PAH. Genetic proxies for SGLT2 inhibition were identified as variants in the SLC5A2 gene that were associated with both levels of gene expression and hemoglobin A1c. Results showed that genetically inferred DM demonstrated a causal correlation with an increased risk of PAH, exhibiting an odds ratio (OR) of 1.432, with a 95% confidence interval (CI) of 1.040-1.973, and a p-value of 0.028. The multivariate MR analysis revealed comparable outcomes after potential confounders (OR = 1.469, 95%CI = 1.021-2.115, p = 0.038). Moreover, genetically predicted SGLT2 inhibition was causally linked to a reduced risk of PAH (OR = 1.681*10-7, 95%CI = 7.059*10-12-0.004, p = 0.002). Therefore, our study identified the suggestively causal effect of DM on the risk of PAH, and SGLT2 inhibition may be a potential therapeutic target in patients with PAH.


Subject(s)
Diabetes Mellitus, Type 2 , Pulmonary Arterial Hypertension , Humans , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/complications , Blood Glucose , Pulmonary Arterial Hypertension/complications , Mendelian Randomization Analysis , Sodium-Glucose Transporter 2/genetics , Sodium-Glucose Transporter 2/therapeutic use , Glycated Hemoglobin , Polymorphism, Single Nucleotide
10.
Angew Chem Int Ed Engl ; 63(8): e202317942, 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38179820

ABSTRACT

CO2 electroreduction (CO2 R) operating in acidic media circumvents the problems of carbonate formation and CO2 crossover in neutral/alkaline electrolyzers. Alkali cations have been universally recognized as indispensable components for acidic CO2 R, while they cause the inevitable issue of salt precipitation. It is therefore desirable to realize alkali-cation-free CO2 R in pure acid. However, without alkali cations, stabilizing *CO2 intermediates by catalyst itself at the acidic interface poses as a challenge. Herein, we first demonstrate that a carbon nanotube-supported molecularly dispersed cobalt phthalocyanine (CoPc@CNT) catalyst provides the Co single-atom active site with energetically localized d states to strengthen the adsorbate-surface interactions, which stabilizes *CO2 intermediates at the acidic interface (pH=1). As a result, we realize CO2 conversion to CO in pure acid with a faradaic efficiency of 60 % at pH=2 in flow cell. Furthermore, CO2 is successfully converted in cation exchanged membrane-based electrode assembly with a faradaic efficiency of 73 %. For CoPc@CNT, acidic conditions also promote the intrinsic activity of CO2 R compared to alkaline conditions, since the potential-limiting step, *CO2 to *COOH, is pH-dependent. This work provides a new understanding for the stabilization of reaction intermediates and facilitates the designs of catalysts and devices for acidic CO2 R.

11.
Science ; 383(6679): 212-219, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38207038

ABSTRACT

We expand the concept of epitaxy to a regime of "twisted epitaxy" with the epilayer crystal orientation between two substrates influenced by their relative orientation. We annealed nanometer-thick gold (Au) nanoparticles between two substrates of exfoliated hexagonal molybdenum disulfide (MoS2) with varying orientation of their basal planes with a mutual twist angle ranging from 0° to 60°. Transmission electron microscopy studies show that Au aligns midway between the top and bottom MoS2 when the twist angle of the bilayer is small (<~7°). For larger twist angles, Au has only a small misorientation with the bottom MoS2 that varies approximately sinusoidally with twist angle of the bilayer MoS2. Four-dimensional scanning transmission electron microscopy analysis further reveals a periodic strain variation (<|±0.5%|) in the Au nanodisks associated with the twisted epitaxy, consistent with the Moiré registry of the two MoS2 twisted layers.

12.
Chin Med J (Engl) ; 137(1): 82-86, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-37646132

ABSTRACT

INTRODUCTION: Observational studies have revealed an association between waist circumference (WC) and atrial fibrillation (AF). However, it is difficult to infer a causal relationship from observational studies because the observed associations could be confounded by unknown risk factors. Therefore, the causal role of WC in AF is unclear. This study was designed to investigate the causal association between WC and AF using a two-sample Mendelian randomization (MR) analysis. METHODS: In our two-sample MR analysis, the genetic variation used as an instrumental variable for MR was acquired from a genome-wide association study (GWAS) of WC (42 single nucleotide polymorphisms with a genetic significance of P <5 × 10 -8 ). The data of WC (from the Genetic Investigation of ANthropometric Traits consortium, containing 232,101 participants) and the data of AF (from the European Bioinformatics Institute database, containing 55,114 AF cases and 482,295 controls) were used to assess the causal role of WC on AF. Three different approaches (inverse variance weighted [IVW], MR-Egger, and weighted median regression) were used to ensure that our results more reliable. RESULTS: All three MR analyses provided evidence of a positive causal association between high WC and AF. High WC was suggested to increase the risk of AF based on the IVW method (odds ratio [OR] = 1.43, 95% confidence interval [CI], 1.30-1.58, P = 2.51 × 10 -13 ). The results of MR-Egger and weighted median regression exhibited similar trends (MR-Egger OR = 1.40 [95% CI, 1.08-1.81], P = 1.61 × 10 -2 ; weighted median OR = 1.39 [95% CI, 1.21-1.61], P = 1.62 × 10 -6 ). MR-Egger intercepts and funnel plots showed no directional pleiotropic effects between high WC and AF. CONCLUSIONS: Our findings suggest that greater WC is associated with an increased risk of AF. Taking measures to reduce WC may help prevent the occurrence of AF.


Subject(s)
Atrial Fibrillation , Humans , Atrial Fibrillation/genetics , Genome-Wide Association Study , Waist Circumference/genetics , Computational Biology , Databases, Factual
13.
ACS Nano ; 18(1): 337-346, 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38113246

ABSTRACT

Layered oxides are widely accepted to be promising cathode candidate materials for K-ion batteries (KIBs) in terms of their rich raw materials and low price, while their further applications are restricted by sluggish kinetics and poor structural stability. Here, the high-entropy design concept is introduced into layered KIB cathodes to address the above issues, and an example of high-entropy layered K0.45Mn0.60Ni0.075Fe0.075Co0.075Ti0.10Cu0.05Mg0.025O2 (HE-KMO) is successfully prepared. Benefiting from the high-entropy oxide with multielement doping, the developed HE-KMO exhibits half-metallic oxide features with a narrow bandgap of 0.19 eV. Increased entropy can also reduce the surface energy of the {010} active facets, resulting in about 2.6 times more exposure of the {010} active facets of HE-KMO than the low-entropy K0.45MnO2 (KMO). Both can effectively improve the kinetics in terms of electron conduction and K+ diffusion. Furthermore, high entropy can inhibit space charge ordering during K+ (de)insertion, and the transition metal-oxygen covalent interaction of HE-KMO is also enhanced, leading to suppressed phase transition of HE-KMO in 1.5-4.2 V and better electrochemical stability of HE-KMO (average capacity drop of 0.20%, 200 cycles) than the low-entropy KMO (average capacity drop of 0.41%, 200 cycles) in the wide voltage window.

15.
Ultrason Sonochem ; 101: 106683, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37948893

ABSTRACT

In this study, we aimed to investigate the impact of various ultrasound durations on the structure and bioactivity of sweet corncob polysaccharides treated with ultrasound-assisted degradation using hydrogen peroxide and ascorbic acid (H2O2-Vc). We subjected sweet corncob polysaccharides to ultrasound treatment for 0, 30, 60, and 90 min alongside the H2O2-Vc method. We then analyzed their chemical composition and structure. Additionally, we administered these polysaccharides to mice with type 2 diabetes (T2DM) through gavage at a dosage of 200 mg/kg/day. The results indicated a significant reduction in the molecular weight of the degraded sweet corncob polysaccharides, while their composition remained relatively stable. However, the basic structure of the polysaccharides was retained. In vivo experiments demonstrated that ultrasound-assisted degradation of these polysaccharides had a positive impact on T2DM, particularly the 60-minute ultrasound treatment (UH-DSCBP-60 min), which effectively controlled blood glucose levels by regulating glycolipid metabolism in the livers of mice with T2DM. This approach also reduced inflammation and oxidative stress levels and inhibited disaccharide activity in the small intestine. We demonstrated that ultrasound can positively affect the sweet corncob polysaccharides hypoglycemic activity. The findings of our study provide a theoretical foundation for the valuable utilization of sweet corncob polysaccharides.


Subject(s)
Ascorbic Acid , Diabetes Mellitus, Type 2 , Animals , Mice , Ascorbic Acid/chemistry , Diabetes Mellitus, Type 2/drug therapy , Hydrogen Peroxide/chemistry , Zea mays/chemistry , Polysaccharides/chemistry
16.
Nat Commun ; 14(1): 5210, 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37626068

ABSTRACT

Na Super Ionic Conductor (NASICON) materials are an important class of solid-state electrolytes owing to their high ionic conductivity and superior chemical and electrochemical stability. In this paper, we combine first-principles calculations, experimental synthesis and testing, and natural language-driven text-mined historical data on NASICON ionic conductivity to achieve clear insights into how chemical composition influences the Na-ion conductivity. These insights, together with a high-throughput first-principles analysis of the compositional space over which NASICONs are expected to be stable, lead to the successful synthesis and electrochemical investigation of several new NASICONs solid-state conductors. Among these, a high ionic conductivity of 1.2 mS cm-1 could be achieved at 25 °C. We find that the ionic conductivity increases with average metal size up to a certain value and that the substitution of PO4 polyanions by SiO4 also enhances the ionic conductivity. While optimal ionic conductivity is found near a Na content of 3 per formula unit, the exact optimum depends on other compositional variables. Surprisingly, the Na content enhances the ionic conductivity mostly through its effect on the activation barrier, rather than through the carrier concentration. These deconvoluted design criteria may provide guidelines for the design of optimized NASICON conductors.

17.
Thromb Res ; 229: 243-251, 2023 09.
Article in English | MEDLINE | ID: mdl-37591154

ABSTRACT

INTRODUCTION: The association between bleeding and subsequent major adverse cardiac and cerebrovascular events (MACCE) remains poorly characterized. We aimed to evaluate the impact of hemorrhagic events in patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI). MATERIALS AND METHODS: A total of 1877 consecutive patients with AF and ACS or undergoing PCI were prospectively recruited. The primary endpoint was MACCE, including all-cause death, myocardial infarction, ischemic stroke, systemic embolism or ischemia-driven revascularization during follow-up. Post-discharge bleeding was graded according to TIMI criteria. Associations between bleeding and subsequent MACCE were examined using time-dependent multivariate Cox regression after adjusting for baseline covariates and the time from bleeding. RESULTS: During a median follow-up of 34.2 months, 341 (18.2 %) had TIMI major or minor bleeding events, of whom 86 (25.2 %) also experienced MACCE. The risk of MACCE was significantly higher in patients with bleeding than those without (8.85 % versus 6.99 % per patient-year; HR, 1.568, 95 % CI, 1.232-1.994). In patients who had both bleeding and MACCE, 65.1 % (56 of 86) bleeding events occurred first. Temporal gradients in MACCE risk after major bleeding was highest within 30 days (HRadj, 23.877; 95 % CI, 12.810-44.506) and remained significant beyond 1 year (HRadj, 3.640; 95 % CI, 1.278-10.366). Minor bleeding was associated with increased risk of MACCE within 1 year. CONCLUSIONS: In patients with AF and ACS or PCI, major and minor bleeding were associated with subsequent MACCE with time-dependency. Our findings may aid in better defining net clinical benefit of optimal antithrombotic therapy.


Subject(s)
Acute Coronary Syndrome , Atrial Fibrillation , Percutaneous Coronary Intervention , Humans , Atrial Fibrillation/complications , Acute Coronary Syndrome/complications , Aftercare , Percutaneous Coronary Intervention/adverse effects , Patient Discharge , Hemorrhage/etiology
18.
Proc Natl Acad Sci U S A ; 120(31): e2301260120, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37487097

ABSTRACT

Lithium-sulfur (Li-S) batteries with high energy density and low cost are promising for next-generation energy storage. However, their cycling stability is plagued by the high solubility of lithium polysulfide (LiPS) intermediates, causing fast capacity decay and severe self-discharge. Exploring electrolytes with low LiPS solubility has shown promising results toward addressing these challenges. However, here, we report that electrolytes with moderate LiPS solubility are more effective for simultaneously limiting the shuttling effect and achieving good Li-S reaction kinetics. We explored a range of solubility from 37 to 1,100 mM (based on S atom, [S]) and found that a moderate solubility from 50 to 200 mM [S] performed the best. Using a series of electrolyte solvents with various degrees of fluorination, we formulated the Single-Solvent, Single-Salt, Standard Salt concentration with Moderate LiPSs solubility Electrolytes (termed S6MILE) for Li-S batteries. Among the designed electrolytes, Li-S cells using fluorinated-1,2-diethoxyethane S6MILE (F4DEE-S6MILE) showed the highest capacity of 1,160 mAh g-1 at 0.05 C at room temperature. At 60 °C, fluorinated-1,4-dimethoxybutane S6MILE (F4DMB-S6MILE) gave the highest capacity of 1,526 mAh g-1 at 0.05 C and an average CE of 99.89% for 150 cycles at 0.2 C under lean electrolyte conditions. This is a fivefold increase in cycle life compared with other conventional ether-based electrolytes. Moreover, we observed a long calendar aging life, with a capacity increase/recovery of 4.3% after resting for 30 d using F4DMB-S6MILE. Furthermore, the correlation between LiPS solubility, degree of fluorination of the electrolyte solvent, and battery performance was systematically investigated.

19.
Nano Lett ; 23(13): 5967-5974, 2023 Jul 12.
Article in English | MEDLINE | ID: mdl-37350461

ABSTRACT

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage systems due to their high theoretical energy density and the low cost of sulfur. However, slow conversion kinetics between the insulating S and lithium sulfide (Li2S) remains as a technical challenge. In this work, we report a catalyst featuring nickel (Ni) single atoms and clusters anchored to a porous hydrogen-substituted graphdiyne support (termed Ni@HGDY), which is incorporated in Li2S cathodes. The rapidly synthesized catalyst was found to enhance ionic and electronic conductivity, decrease the reaction overpotential, and promote more complete conversion between Li2S and sulfur. The addition of Ni@HGDY to commercial Li2S powder enabled a capacity of over 516 mAh gLi2S-1 at 1 C for over 125 cycles, whereas the control Li2S cathode managed to maintain just over 200 mAh gLi2S-1. These findings highlight the efficacy of Ni as a metal catalyst and demonstrate the promise of HGDY in energy storage devices.

20.
Nat Commun ; 14(1): 1275, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36882392

ABSTRACT

A key strategy to design environmental barrier coatings focuses on doping multiple rare-earth principal components into ß-type rare-earth disilicates (RE2Si2O7) to achieve versatile property optimization. However, controlling the phase formation capability of (nRExi)2Si2O7 remains a crucial challenge, due to the complex polymorphic phase competitions and evolutions led by different RE3+ combination. Herein, by fabricating twenty-one model (REI0.25REII0.25REIII0.25REIV0.25)2Si2O7 compounds, we find that their formation capability can be evaluated by the ability to accommodate configurational randomness of multiple RE3+ cations in ß-type lattice while preventing the ß-to-γ polymorphic transformation. The phase formation and stabilization are controlled by the average RE3+ radius and the deviations of different RE3+ combinations. Subsequently, based on high-throughput density-functional-theory calculations, we propose that the configurational entropy of mixing is a reliable descriptor to predict the phase formation of ß-type (nRExi)2Si2O7. The results may accelerate the design of (nRExi)2Si2O7 materials with tailored compositions and controlled polymorphic phases.

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