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1.
Nat Commun ; 15(1): 3778, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38710689

ABSTRACT

Lithium-ion batteries with fast-charging/discharging properties are urgently needed for the mass adoption of electric vehicles. Here, we show that fast charging/discharging, long-term stable and high energy charge-storage properties can be realized in an artificial electrode made from a mixed electronic/ionic conductor material (Fe/LixM, where M = O, F, S, N) enabled by a space charge principle. Particularly, the Fe/Li2O electrode is able to be charged/discharged to 126 mAh g-1 in 6 s at a high current density of up to 50 A g-1, and it also shows stable cycling performance for 30,000 cycles at a current density of 10 A g-1, with a mass-loading of ~2.5 mg cm-2 of the electrode materials. This study demonstrates the critical role of the space charge storage mechanism in advancing electrochemical energy storage and provides an unconventional perspective for designing high-performance anode materials for lithium-ion batteries.

2.
Chem Commun (Camb) ; 60(41): 5459-5462, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38689549

ABSTRACT

The lack of suitable cathode materials has hampered the further development of calcium-ion batteries (CIBs). A novel composite cathode material, namely BaV6O16·3H2O@GO, was fabricated, which delivers a high specific capacity of 285.72 mA h g-1 at 50 mA g-1 after 50 cycles and a long cycle life, benefiting from a large layer spacing and robust structure. This study provides guidance for the development of vanadium-based cathode materials for CIBs.

3.
Adv Mater ; : e2401048, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38760981

ABSTRACT

The emergence of layered sodium transition metal oxides featuring a multiphase structure presents a promising approach for cathode materials in sodium-ion batteries, showcasing notably improved energy storage capacity. However, the advancement of cathodes with multiphase structures faces obstacles due to the limited understanding of the integrated structural effects. Herein, the integrated structural effects by an in-depth structure-chemistry analysis in the developed layered cathode system NaxCu0.1Co0.1Ni0.25Mn0.4Ti0.15O2 with purposely designed P2/O3 phase integration, are comprehended. The results affirm that integrated phase ratio plays a pivotal role in electrochemical/structural stability, particularly at high voltage and with the incorporation of anionic redox. In contrast to previous reports advocating solely for the enhanced electrochemical performance in biphasic structures, it is demonstrated that an inappropriate composite structure is more destructive than a single-phase design. The in situ X-ray diffraction results, coupled with density functional theory computations further confirm that the biphasic structure with P2:O3 = 4:6 shows suppressed irreversible phase transition at high desodiated states and thus exhibits optimized electrochemical performance. These fundamental discoveries provide clues to the design of high-performance layered oxide cathodes for next-generation SIBs.

4.
J Agric Food Chem ; 72(20): 11716-11723, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38728745

ABSTRACT

A total of 32 novel sulfoximines bearing cyanoguanidine and nitroguanidine moieties were designed and synthesized by a rational molecule design strategy. The bioactivities of the title compounds were evaluated and the results revealed that some of the target compounds possessed excellent antifungal activities against six agricultural fungi, including Sclerotinia sclerotiorum, Fusarium graminearum, Phytophthora capsici, Botrytis cinerea, Rhizoctonia solani, and Pyricularia grisea. Among them, compounds 8e1 and 8e4 exhibited significant efficacy against P. grisea with EC50 values of 2.72 and 2.98 µg/mL, respectively, which were much higher than that of commercial fungicides boscalid (47.95 µg/mL). Interestingly, in vivo assays determined compound 8e1 possessed outstanding activity against S. sclerotiorum with protective and curative effectiveness of 98 and 95.6% at 50 µg/mL, which were comparable to those of boscalid (93.2, 91.9%). The further preliminary mechanism investigation disclosed that compound 8e1 could damage the structure of the cell membrane of S. sclerotiorum, increase its permeability, and suppress its growth. Overall, the findings enhanced that these novel sulfoximine derivatives could be potential lead compounds for the development of new fungicides.


Subject(s)
Drug Design , Fungicides, Industrial , Fusarium , Guanidines , Plant Diseases , Rhizoctonia , Fungicides, Industrial/pharmacology , Fungicides, Industrial/chemistry , Fungicides, Industrial/chemical synthesis , Guanidines/chemistry , Guanidines/pharmacology , Guanidines/chemical synthesis , Structure-Activity Relationship , Rhizoctonia/drug effects , Rhizoctonia/growth & development , Fusarium/drug effects , Fusarium/growth & development , Plant Diseases/microbiology , Phytophthora/drug effects , Phytophthora/growth & development , Ascomycota/drug effects , Ascomycota/growth & development , Botrytis/drug effects , Botrytis/growth & development , Molecular Structure
5.
Proc Natl Acad Sci U S A ; 121(7): e2320030121, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38315861

ABSTRACT

Transition metals and related compounds are known to exhibit high catalytic activities in various electrochemical reactions thanks to their intriguing electronic structures. What is lesser known is their unique role in storing and transferring electrons in battery electrodes which undergo additional solid-state conversion reactions and exhibit substantially large extra capacities. Here, a full dynamic picture depicting the generation and evolution of electrochemical interfaces in the presence of metallic nanoparticles is revealed in a model CoCO3/Li battery via an in situ magnetometry technique. Beyond the conventional reduction to a Li2CO3/Co mixture under battery operation, further decomposition of Li2CO3 is realized by releasing interfacially stored electrons from its adjacent Co nanoparticles, whose subtle variation in the electronic structure during this charge transfer process has been monitored in real time. The findings in this work may not only inspire future development of advanced electrode materials for next-generation energy storage devices but also open up opportunities in achieving in situ monitoring of important electrocatalytic processes in many energy conversion and storage systems.

6.
NPJ Vaccines ; 9(1): 50, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38424078

ABSTRACT

Trivalent oral poliovirus vaccine (tOPV) has been withdrawn and instead an inactivated poliovirus vaccine (IPV) and bivalent type 1 and type 3 OPV (bOPV) sequential immunization schedule has been implemented since 2016, but no immune persistence data are available for this polio vaccination strategy. This study aimed to assess immune persistence following different polio sequential immunization schedules. Venous blood was collected at 24, 36, and 48 months of age from participants who had completed sequential schedules of combined IPV and OPV in phase III clinical trials. The serum neutralizing antibody titers against poliovirus were determined, and the poliovirus-specific antibody-positive rates were evaluated. A total of 1104 participants were enrolled in this study. The positive rates of poliovirus type 1- and type 3-specific antibodies among the sequential immunization groups showed no significant difference at 24, 36, or 48 months of age. The positive rates of poliovirus type 2-specific antibody in the IPV-IPV-tOPV group at all time points were nearly 100%, which was significantly higher than the corresponding rates in other immunization groups (IPV-bOPV-bOPV and IPV-IPV-bOPV). Immunization schedules involving one or two doses of IPV followed by bOPV failed to maintain a high positive rate for poliovirus type 2-specific antibody.

7.
Front Bioeng Biotechnol ; 12: 1361966, 2024.
Article in English | MEDLINE | ID: mdl-38410166

ABSTRACT

The mitochondria act as the main producers of reactive oxygen species (ROS) within cells. Elevated levels of ROS can activate the mitochondrial apoptotic pathway, leading to cell apoptosis. In this study, we devised a molecular prodrug named CTT2P, demonstrating notable efficacy in facilitating mitochondrial apoptosis. To develop nanomedicine, we enveloped CTT2P within bovine serum albumin (BSA), resulting in the formulation known as CTT2P@B. The molecular prodrug CTT2P is achieved by covalently conjugating mitochondrial targeting triphenylphosphine (PPh3), photosensitizer TPPOH2, ROS-sensitive thioketal (TK), and chemotherapeutic drug camptothecin (CPT). The prodrug, which is chemically bonded, prevents the escape of drugs while they circulate throughout the body, guaranteeing the coordinated dispersion of both medications inside the organism. Additionally, the concurrent integration of targeted photodynamic therapy and cascade chemotherapy synergistically enhances the therapeutic efficacy of pharmaceutical agents. Experimental results indicated that the covalently attached prodrug significantly mitigated CPT cytotoxicity under dark conditions. In contrast, TPPOH2, CTT2, CTT2P, and CTT2P@B nanoparticles exhibited increasing tumor cell-killing effects and suppressed tumor growth when exposed to light at 660 nm with an intensity of 280 mW cm-2. Consequently, this laser-triggered, mitochondria-targeted, combined photodynamic therapy and chemotherapy nano drug delivery system, adept at efficiently promoting mitochondrial apoptosis, presents a promising and innovative approach to cancer treatment.

8.
RSC Adv ; 14(5): 3122-3134, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38249670

ABSTRACT

Bacterial infections from chronic wounds affect about 175 million people each year and are a significant clinical problem. Through the integration of photodynamic therapy (PDT) and chemotherapy, a new photosensitizer consisting of ammonium salt N,N-bis-(2-hydroxyethyl)-N-(6-(4-(10,15,20-trimesitylporphyrin-5-yl) phenoxy) hexane)-N-methanaminium bromide, TMP(+) was successfully synthesized with a total reaction yield of 10%. The novel photosensitizer consists of two parts, a porphyrin photosensitizer part and a quaternary ammonium salt part, to achieve the synergistic effect of photodynamic and chemical antibacterial activity. With the increase of TMP(+) concentration, the diameter of the PCT fiber membranes (POL/COL/TMP(+); POL, polycaprolactone; COL, collagen) gradually increased, which was caused by the charge of the quaternary ammonium salt. At the same time, the antibacterial properties were gradually improved. We finally selected the PCT 0.5% group for the antibacterial experiment, with excellent performance in fiber uniformity, hydrophobicity and biosafety. The antibacterial experiment showed that the modified porphyrin TMP(+) had a better antibacterial effect than others. In vivo chronic wound healing experiments proved that the antibacterial and anti-inflammatory effect of the PCTL group was the best, further confirmed by H&E histological analysis, immunofluorescence and immunohistochemistry mechanism experiments. This research lays the foundation for the manufacture of novel molecules that combine chemical and photodynamic strategies.

9.
Chinese Journal of Biologicals ; (12): 361-369, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1013402

ABSTRACT

@#Pertussis is an ancient disease,and early vaccination has greatly reduced the incidence and mortality of pertussis.However,the pertussis resurgence has been reported worldwide in recent years.Further understanding of the epidemiological characteristics of pertussis is essential for the development of more effective pertussis vaccines and for better prevention and control and early elimination of pertussis.This paper mainly reviews the basic epidemiological characteristics,seroepidemiological characteristics,molecular epidemiological characteristics and prevention and control progress of pertussis at home and abroad.

10.
Angew Chem Int Ed Engl ; 63(6): e202318444, 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38116912

ABSTRACT

Zn-MnO2 batteries have attracted extensive attention for grid-scale energy storage applications, however, the energy storage chemistry of MnO2 in mild acidic aqueous electrolytes remains elusive and controversial. Using α-MnO2 as a case study, we developed a methodology by coupling conventional coin batteries with customized beaker batteries to pinpoint the operating mechanism of Zn-MnO2 batteries. This approach visually simulates the operating state of batteries in different scenarios and allows for a comprehensive study of the operating mechanism of aqueous Zn-MnO2 batteries under mild acidic conditions. It is validated that the electrochemical performance can be modulated by controlling the addition of Mn2+ to the electrolyte. The method is utilized to systematically eliminate the possibility of Zn2+ and/or H+ intercalation/de-intercalation reactions, thereby confirming the dominance of the MnO2 /Mn2+ dissolution-deposition mechanism. By combining a series of phase and spectroscopic characterizations, the compositional, morphological and structural evolution of electrodes and electrolytes during battery cycling is probed, elucidating the intrinsic battery chemistry of MnO2 in mild acid electrolytes. Such a methodology developed can be extended to other energy storage systems, providing a universal approach to accurately identify the reaction mechanism of aqueous aluminum-ion batteries as well.

11.
Proc Natl Acad Sci U S A ; 120(48): e2314362120, 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-37983507

ABSTRACT

Interfacial catalysis occurs ubiquitously in electrochemical systems, such as batteries, fuel cells, and photocatalytic devices. Frequently, in such a system, the electrode material evolves dynamically at different operating voltages, and this electrochemically driven transformation usually dictates the catalytic reactivity of the material and ultimately the electrochemical performance of the device. Despite the importance of the process, comprehension of the underlying structural and compositional evolutions of the electrode material with direct visualization and quantification is still a significant challenge. In this work, we demonstrate a protocol for studying the dynamic evolution of the electrode material under electrochemical processes by integrating microscopic and spectroscopic analyses, operando magnetometry techniques, and density functional theory calculations. The presented methodology provides a real-time picture of the chemical, physical, and electronic structures of the material and its link to the electrochemical performance. Using Co(OH)2 as a prototype battery electrode and by monitoring the Co metal center under different applied voltages, we show that before a well-known catalytic reaction proceeds, an interfacial storage process occurs at the metallic Co nanoparticles/LiOH interface due to injection of spin-polarized electrons. Subsequently, the metallic Co nanoparticles act as catalytic activation centers and promote LiOH decomposition by transferring these interfacially residing electrons. Most intriguingly, at the LiOH decomposition potential, electronic structure of the metallic Co nanoparticles involving spin-polarized electrons transfer has been shown to exhibit a dynamic variation. This work illustrates a viable approach to access key information inside interfacial catalytic processes and provides useful insights in controlling complex interfaces for wide-ranging electrochemical systems.

12.
Chem Sci ; 14(43): 12219-12230, 2023 Nov 08.
Article in English | MEDLINE | ID: mdl-37969610

ABSTRACT

The solid-electrolyte-interphase (SEI) plays a critical role in lithium-ion batteries (LIBs) because of its important influence on electrochemical performance, such as cycle stability, coulombic efficiency, etc. Although LiOH has been recognized as a key component of the SEI, its influence on the SEI and electrochemical performance has not been well clarified due to the difficulty in precisely controlling the LiOH content and characterize the detailed interface reactions. Here, a gradual change of LiOH content is realized by different reduction schemes among Co(OH)2, CoOOH and CoO. With reduced Co nanoparticles as magnetic "probes", SEI characterization is achieved by operando magnetometry. By combining comprehensive characterization and theoretical calculations, it is verified that LiOH leads to a composition transformation from lithium ethylene di-carbonate (LEDC) to lithium ethylene mono-carbonate (LEMC) in the SEI and ultimately results in capacity decay. This work unfolds the detailed SEI reaction scenario involving LiOH, provides new insights into the influence of SEI composition, and has value for the co-development between the electrode materials and electrolyte.

13.
Pest Manag Sci ; 79(4): 1273-1283, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36308727

ABSTRACT

BACKGROUND: Fungicides play a significant role in the integrated management of plant pathogens. However, the irrational application of fungicides with similar structures has led to development of cross-resistance, therefore there is a need to seek novel fungicides with new structures. RESULTS: Twenty-eight novel sulfoximine derivatives incorporating nitroguanidine moieties were designed, synthesized, and evaluated as antifungal agents. The bioassay results indicated that most of the synthesized compounds displayed excellent fungicidal activities against Sclerotinia sclerotiorum, Rhizoctonia solani, Fusarium graminearum, and Pyricularia grisea. Among these, compounds 6c4 , 6c5 , and 6c6 exhibited remarkable fungicidal activities against P. grisea, with EC50 values of 1.28, 1.17, and 1.68 µg mL-1 , respectively. In addition, compound 6c2 displayed the most potent activity against S. sclerotiorum (EC50  = 3.64 µg mL-1 ). Further in vivo fungicidal activity screening against S. sclerotiorum demonstrated that the protective and curative effects of compound 6c2 were 98.1% and 91.3% at 25 µg mL-1 , respectively, comparable to that of boscalid (94.4%, 89.6%). The preliminary mechanism study found that the hyphae of S. sclerotiorum treated with compound 6c2 was abnormal with mycelial collapse and membrane permeability increase. The present findings can help to develop new fungicides for crop protection. CONCLUSION: Novel sulfoximine derivatives containing nitroguanidine possess potential antifungal activity, and the unique structure may offer an alternative option for fungicide development in the future. © 2022 Society of Chemical Industry.


Subject(s)
Antifungal Agents , Fungicides, Industrial , Antifungal Agents/pharmacology , Fungicides, Industrial/pharmacology , Structure-Activity Relationship , Guanidines
14.
Adv Mater ; 35(8): e2207353, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36479745

ABSTRACT

Ferromagnetic metals show great prospects in ultralow-power-consumption spintronic devices, due to their high Curie temperature and robust magnetization. However, there is still a lack of reliable solutions for giant and reversible voltage control of magnetism in ferromagnetic metal films. Here, a novel space-charge approach is proposed which allows for achieving a modulation of 30.3 emu/g under 1.3 V in Co/TiO2 multilayer granular films. The robust endurance with more than 5000 cycles is demonstrated. Similar phenomena exist in Ni/TiO2 and Fe/TiO2 multilayer granular films, which shows its universality. The magnetic change of 107% in Ni/TiO2 underlines its potential in a voltage-driven ON-OFF magnetism. Such giant and reversible voltage control of magnetism can be ascribed to space-charge effect at the ferromagnetic metals/TiO2 interfaces, in which spin-polarized electrons are injected into the ferromagnetic metal layer with the adsorption of lithium-ions on the TiO2 surface. These results open the door for a promising method to modulate the magnetization in ferromagnetic metals, paving the way toward the development of ionic-magnetic-electric coupled applications.

15.
Nano Lett ; 22(24): 10102-10110, 2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36475731

ABSTRACT

The electrochemical performance of electrode materials is largely dependent on the structural and chemical evolutions during the charge-discharge processes. Hence, revealing ion storage chemistry could enlighten mechanistic understanding and offer guidance for rational design for energy storage materials. Here, we investigate the mechanisms of potassium (K)-ion storage in the promising bimetal oxide materials by in situ magnetometry. We focus on a single-phased hollow FeTiO3 (SPH-FTO) hexagonal prism synthesized through a complexing-reagent assisted approach and find that the K-ion storage in this compound occurs predominantly with an intercalation mechanism and fractionally a conversion mechanism. We also demonstrate a K-ion hybrid capacitor assembled with the prepared SPH-FTO hexagonal prism anode and activated carbon cathode, delivering a high energy density and high power density as well as extraordinary cycling stability. This new understanding is used to showcase the inherently high K-ion storage properties from the earth-abundant FeTiO3.

16.
Sci Bull (Beijing) ; 67(11): 1145-1153, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-36545981

ABSTRACT

Interfacial space charge storage between ionic and electronic conductor is a promising scheme to further improve energy and power density of alkali metal ion batteries (AMIBs). However, the general behavior of space charge storage in AMIBs has been less investigated experimentally, mostly due to the complicated electrochemical behavior and lack of proper characterization techniques. Here, we use operando magnetometry to verify that in FeSe2 AMIBs, abundant Li+/Na+/K+ (M+) can be stored at M2Se phase while electrons accumulate at Fe nanoparticles, forming interfacial space charge layers. Magnetic and dynamics tests further demonstrate that with increasing ionic radius from Li+, Na+ to K+, the reaction kinetics can be hindered, resulting in limited Fe formation and reduced space charge storage capacity. This work lays solid foundation for studying the complex interfacial effect in electrochemical processes and designing advanced energy storage devices with substantial capacity and considerable power density.

17.
Chem Sci ; 13(47): 14191-14197, 2022 Dec 07.
Article in English | MEDLINE | ID: mdl-36540814

ABSTRACT

Rechargeable aluminum-ion batteries have attracted increasing attention owing to the advantageous multivalent ion storage mechanism thus high theoretical capacity as well as inherent safety and low cost of using aluminum. However, their development has been largely impeded by the lack of suitable positive electrodes to provide both sufficient energy density and satisfactory rate capability. Here we report a candidate positive electrode based on ternary metal oxides, Fe2(MoO4)3, which was assembled by cross-stacking of porous nanosheets, featuring superior rate performance and cycle stability, and most importantly a well-defined discharge voltage plateau near 1.9 V. Specifically, the positive electrode is able to deliver reversible capacities of 239.3 mA h g-1 at 0.2 A g-1 and 73.4 mA h g-1 at 8.0 A g-1, and retains 126.5 mA h g-1 at 1.0 A g-1 impressively, after 2000 cycles. Furthermore, the aluminum-storage mechanism operating on Al3+ intercalation in this positive electrode is demonstrated for the first time via combined in situ and ex situ characterization studies and density functional theory calculations. This work not only explores potential positive electrodes for aluminum-based batteries but also sheds light on the fundamental charge storage mechanism within the electrode.

18.
IUCrdata ; 7(Pt 3): x220342, 2022 Mar.
Article in English | MEDLINE | ID: mdl-36339802

ABSTRACT

In the structure of the title compound, C15H14ClN5O2, the terminal phenyl ring and the adjacent furan ring subtend a dihedral angle of 6.77 (17)°. The 4-chloro-5-(di-methyl-amino)-pyridazin-3(2H)-one group is linked to the oxa-diazole ring by a methyl-ene bridge, and the dihedral angle between the pyridazine and oxa-diazole rings is 88.66 (14)°. In the crystal, C-H⋯O and C-H⋯N hydrogen bonds extend the structure into a three-dimensional network.

19.
Adv Sci (Weinh) ; 9(33): e2203895, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36202622

ABSTRACT

The performance of electrode materials depends intensively on the lithium (Li)-ion storage mechanisms correlating ultimately with the Coulombic efficiency, reversible capacity, and morphology variation of electrode material upon cycling. Transition metal nitrides anode materials have exhibited high-energy density and superior rate capability; however, the intrinsic mechanism is largely unexplored and still unclear. Here, a typical 3D porous Fe2 N micro-coral anode is prepared and, an intercalation-conversion-heterogeneity hybrid Li-ion storage mechanism that is beyond the conventional intercalation or conversion reaction is revealed through various characterization techniques and thermodynamic analysis. Interestingly, using advanced in situ magnetometry, the ratio (ca. 24.4%) of the part where conversion reaction occurs to the entire Fe2 N can further be quantified. By rationally constructing a Li-ion capacitor comprising 3D porous Fe2 N micro-corals anode and commercial AC cathode, the hybrid full device delivers a high energy-density (157 Wh kg-1 ) and high power-density (20 000 W kg-1 ), as well as outstanding cycling stability (93.5% capacitance retention after 5000 cycles). This research provides an original and insightful method to confirm the reaction mechanism of material related to transition metals and a fundamental basis for emerging fast charging electrode materials to be efficiently explored for a next-generation battery.

20.
Chem Commun (Camb) ; 58(78): 10981-10984, 2022 Sep 29.
Article in English | MEDLINE | ID: mdl-36093729

ABSTRACT

A nanocomposite consisting of iron telluride wrapped with graphene oxide (GO) was prepared via a hydrothermal method. As the cathode material for aluminum-ion batteries (AIBs), it exhibited a remarkable long-term cycle performance with a reversible capacity of 120.4 mA h g-1 at 1 A g-1 after 10 000 cycles, i.e., a cyclability better than those of all other transition metal chalcogenides in AIBs reported to date. Furthermore, an energy storage mechanism, involving the intercalation and deintercalation of multiple ions (AlCl4-, Cl- and Al3+), was elucidated. This study offers guidance for further development of transition metal tellurides for AIBs.

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