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1.
Angew Chem Int Ed Engl ; : e202411123, 2024 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-39370396

RESUMEN

Advancing the design of cathode catalysts to significantly maximize platinum utilization and augment the longevity has emerged as a formidable challenge in the field of fuel cells. Herein, we rationally design a high entropy intermetallic compound (HEIC, Pt(FeCoNiCu)3) for catalyzing oxygen reduction reaction (ORR) by an efficient machine learning stategy, where crystal graph convolutional neural networks are employed to expedite the multicomponent design. Based on a dataset generated from first-principles calculations, the model can achieve a high prediction accuracy with mean absolute errors of 0.003 for surface strain and 0.011 eV atom-1 for formation energy. In addition, we identify two chemical features (atomic size difference and mixing enthalpy) as new descriptors to explore advanced ORR catalysts. The carbon supported Pt(FeCoNiCu)3 catalyst with small particle size is successfully synthesized by a freeze-drying-annealing technology, and exhibits ultrahigh mass activity (4.09 A mgPt-1) and specific activity (7.92 mA cm-2). Meanwhile, The catalyst also shows significantly enhanced electrochemical stability which can be ascribed to the sluggish difussion effect in the HEIC structure. Beyond offering a promising low-Pt electrocatalysts for fuel cell cathode, this work offers a new paradigm to rationally design advanced catalysts for energy storage and conversion devices.

2.
Healthcare (Basel) ; 12(18)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39337231

RESUMEN

Objectives: This study aims to examine the geographical variation in physical fitness levels among Chinese children and adolescents in Shaanxi province. Methods: A total of 19,175 children from Shaanxi province with physical fitness data in 2019, participated in the study. Physical fitness was assessed using body mass index, force vital capacity, 50 m sprint, sit and reach, 1 min rope skipping, sit-ups, 50 m × 8 round-trip running, standing long jump, pull-ups, 800 m, and 1000 m running, and their standardized scores were aggregated to form a summary score. The total score is used to classify the physical fitness levels into four grades (excellence to failure). Results: The Guanzhong (GZ) region scored the highest, while Northern Shaanxi (NS) scored the lowest. The excellence rate for physical fitness was highest in GZ and lowest in NS, while the failure rate was highest in NS and lowest in GZ. Notably, children and adolescents in NS demonstrated the best endurance levels despite their overall lower fitness scores. The comprehensive physical fitness among Chinese children and adolescents in Shaanxi province showed significant regional disparities. GZ region exhibited the highest physical fitness levels, while Northern Shaanxi had the lowest. Conclusions: Region-specific interventions and targeted health policies are essential to address these disparities and improve the overall physical health status of children and adolescents in Shaanxi province.

3.
Angew Chem Int Ed Engl ; 63(42): e202410494, 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39007424

RESUMEN

Anion-reinforced solvation structure favors the formation of inorganic-rich robust electrode-electrolyte interface, which endows fast ion transport and high strength modulus to enable improved electrochemical performance. However, such a unique solvation structure inevitably injures the ionic conductivity of electrolytes and limits the fast-charging performance. Herein, a trade-off in tuning anion-reinforced solvation structure and high ionic conductivity is realized by the entropy-assisted hybrid ester-ether electrolyte. Anion-reinforced solvation sheath with more anions occupying the inner Na+ shell is constructed by introducing the weakly coordinated ether tetrahydrofuran into the commonly used ester-based electrolyte, which merits the accelerated desolvation energy and gradient inorganic-rich electrode-electrolyte interface. The improved ionic conductivity is attributed to the weakly diverse solvation structures induced by entropy effect. These enable the enhanced rate performance and cycling stability of Prussian blue||hard carbon full cells with high electrode mass loading. More importantly, the practical application of the designed electrolyte was further demonstrated by industry-level 18650 cylindrical cells.

4.
ACS Appl Mater Interfaces ; 16(27): 35033-35042, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38938082

RESUMEN

Organic material holds immense potential for Li-ion batteries (LIBs) due to their eco-friendly nature, high structural designability, abundant sources, and high theoretical capacity. However, the limited redox-active sites, low electronic conductivity, sluggish ionic diffusion, and high solubility hinder their practical application. Here, we reported the use of a linear polymer called poly(naphthalenetetracarboxylic dianhydride-pyrene-4,5,9,10-tetraone)-coated graphene nanosheets (NPT/rGO) as a cathode material for LIBs. The NPT polymer has a rotation angle of approximately 63° between each plane, which helps in exposing the active sites and preventing structural pulverization during cycling. The highly conjugated skeleton of the polymer, along with graphene, forms a synergistic effect through a π-π interaction. This combination enhances the conductivity and restricts solubility. Additionally, the linear structure of NPT and the two-dimensional rGO substrates work together to enhance charge transfer and ion diffusion rates, resulting in faster reaction kinetics. Consequently, NPT/rGO exhibits excellent electrochemical performance in terms of high capacity, superior cyclic stability, and good rate capability for LIBs. Moreover, through the combination of experimental investigations and theoretical simulations, a multiple electron reaction mechanism, an efficient Li-ion storage behavior, and a reversible dynamic evolution have been revealed. This study introduces a rational molecular design approach to enhance the electrochemical performance of polyimide derivatives, thereby contributing to the advancement of cutting-edge organic electrode materials for LIBs.

5.
J Am Chem Soc ; 146(22): 15219-15229, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38775440

RESUMEN

Unraveling the catalyst surface structure and behavior during reactions is essential for both mechanistic understanding and performance optimization. Here we report a phenomenon of facet-dependent surface restructuring intrinsic to ß-Ni(OH)2 catalysts during oxygen evolution reaction (OER), discovered by the correlative ex situ and operando characterization. The ex situ study after OER reveals ß-Ni(OH)2 restructuring at the edge facets to form nanoporous Ni1-xO, which is Ni deficient containing Ni3+ species. Operando liquid transmission electron microscopy (TEM) and Raman spectroscopy further identify the active role of the intermediate ß-NiOOH phase in both the OER catalysis and Ni1-xO formation, pinpointing the complete surface restructuring pathway. Such surface restructuring is shown to effectively increase the exposed active sites, accelerate Ni oxidation kinetics, and optimize *OH intermediate bonding energy toward fast OER kinetics, which leads to an extraordinary activity enhancement of ∼16-fold. Facilitated by such a self-activation process, the specially prepared ß-Ni(OH)2 with larger edge facets exhibits a 470-fold current enhancement than that of the benchmark IrO2, demonstrating a promising way to optimize metal-(oxy)hydroxide-based catalysts.

6.
ACS Nano ; 18(20): 12981-12993, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38717035

RESUMEN

Aqueous aluminum-ion batteries (AAIBs) are considered as a promising alternative to lithium-ion batteries due to their large theoretical capacity, high safety, and low cost. However, the uneven deposition, hydrogen evolution reaction (HER), and corrosion during cycling impede the development of AAIBs, especially under a harsh environment. Here, a hydrated eutectic electrolyte (AATH40) composed of Al(OTf)3, acetonitrile (AN), triethyl phosphate (TEP), and H2O was designed to improve the electrochemical performance of AAIBs in a wide temperature range. The combination of molecular dynamics simulations and spectroscopy analysis reveals that AATH40 has a less-water-solvated structure [Al(AN)2(TEP)(OTf)2(H2O)]3+, which effectively inhibits side reactions, decreases the freezing point, and extends the electrochemical window of the electrolyte. Furthermore, the formation of a solid electrolyte interface, which effectively inhibits HER and corrosion, has been demonstrated by X-ray photoelectron spectroscopy, X-ray diffraction tests, and in situ differential electrochemical mass spectrometry. Additionally, operando synchrotron Fourier transform infrared spectroscopy and electrochemical quartz crystal microbalance with dissipation monitoring reveal a three-electron storage mechanism for the Al//polyaniline full cells. Consequently, AAIBs with this electrolyte exhibit improved cycling stability within the temperature range of -10-50 °C. This present study introduces a promising methodology for designing electrolytes suitable for low-cost, safe, and stable AAIBs over a wide temperature range.

7.
Small ; 20(31): e2400381, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38639308

RESUMEN

Pt-based intermetallic compounds (IMCs) are considered as a class of promising fuel cell electrocatalysts, owing to their outstanding intrinsic activity and durability. However, the synthesis of uniformly dispersed IMCs with small sizes presents a formidable challenge during the essential high-temperature annealing process. Herein, a facile and generally applicable VOx matrix confinement strategy is demonstrated for the controllable synthesis of ordered L10-PtM (M = Fe, Co, and Mn) nanoparticles, which not only enhances the dispersion of intermetallic nanocrystals, even at high loading (40 wt%), but also simplifies the oxide removal and acid-washing procedures. Taking intermetallic PtCo as an example, the as-prepared catalyst displays a high-performance oxygen reduction activity (mass activity of 1.52 A mgPt -1) and excellent stability in the membrane electrode assemblies (MEAs) (the ECSA has just 7% decay after durability test). This strategy provides an economical and scalable route for the controlled synthesis of Pt-based intermetallic catalysts, which can pave a way for the commercialization of fuel cell technologies.

8.
Chem Sci ; 15(12): 4341-4348, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38516068

RESUMEN

Organic electrode materials have shown significant potential for aqueous Zn ion batteries (AZIBs) due to their flexible structure designability and cost advantage. However, sluggish ionic diffusion, high solubility, and low capacities limit their practical application. Here, we designed a covalent organic framework (TA-PTO-COF) generated by covalently bonding tris(4-formylbiphenyl)amine (TA) and 2,7-diaminopyrene-4,5,9,10-tetraone (PTO-NH2). The highly conjugated skeleton inside enhances its electron delocalization and intermolecular interaction, leading to high electronic conductivity and limited solubility. The open channel within the TA-PTO-COF provides ionic diffusion pathways for fast reaction kinetics. In addition, the abundant active sites (C[double bond, length as m-dash]N and C[double bond, length as m-dash]O) endow the TA-PTO-COF with a large reversible capacity. As a result, the well-designed TA-PTO-COF cathode delivers exceptional capacity (255 mA h g-1 at 0.1 A g-1), excellent cycling stability, and a superior rate capacity of 186 mA h g-1 at 10 A g-1. Additionally, the co-insertion mechanism of Zn2+/H+ within the TA-PTO-COF cathode is revealed in depth by ex situ spectroscopy. This study presents an effective strategy for developing high-performance organic cathodes for advanced AZIBs.

9.
Adv Mater ; 36(24): e2400642, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38428042

RESUMEN

Achieving reversible insertion/extraction in most cathodes for aqueous aluminum ion batteries (AAIBs) is a significant challenge due to the high charge density of Al3+ and strong electrostatic interactions. Organic materials facilitate the hosting of multivalent carriers and rapid ions diffusion through the rearrangement of chemical bonds. Here, a bipolar conjugated poly(2,3-diaminophenazine) (PDAP) on carbon substrates prepared via a straightforward electropolymerization method is introduced as cathode for AAIBs. The integration of n-type and p-type active units endow PDAP with an increased number of sites for ions interaction. The long-range conjugated skeleton enhances electron delocalization and collaborates with carbon to ensure high conductivity. Moreover, the strong intermolecular interactions including π-π interaction and hydrogen bonding significantly enhance its stability. Consequently, the Al//PDAP battery exhibits a large capacity of 338 mAh g-1 with long lifespan and high-rate capability. It consistently demonstrates exceptional electrochemical performances even under extreme conditions with capacities of 155 and 348 mAh g-1 at -20 and 45 °C, respectively. In/ex situ spectroscopy comprehensively elucidates its cation/anion (Al3+/H3O+ and ClO4 -) storage with 3-electron transfer in dual electroactive centers (C═N and -NH-). This study presents a promising strategy for constructing high-performance organic cathode for AAIBs over a wide temperature range.

10.
Adv Mater ; 36(23): e2313835, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38427844

RESUMEN

Multinary metal chalcogenides hold considerable promise for high-energy potassium storage due to their numerous redox reactions. However, challenges arise from issues such as volume expansion and sluggish kinetics. Here, a design featuring a layered ternary Bi0.4Sb1.6Te3 anchored on graphene layers as a composite anode, where Bi atoms act as a lattice softening agent on Sb, is presented. Benefiting from the lattice arrangement in Bi0.4Sb1.6Te3 and structure, Bi0.4Sb1.6Te3/graphene exhibits a mitigated expansion of 28% during the potassiation/depotassiation process and demonstrates facile K+ ion transfer kinetics, enabling long-term durability of 500 cycles at various high rates. Operando synchrotron diffraction patterns and spectroscopies including in situ Raman, ex situ adsorption, and X-ray photoelectron reveal multiple conversion and alloying/dealloying reactions for potassium storage at the atomic level. In addition, both theoretical calculations and electrochemical examinations elucidate the K+ migration pathways and indicate a reduction in energy barriers within Bi0.4Sb1.6Te3/graphene, thereby suggesting enhanced diffusion kinetics for K+. These findings provide insight in the design of durable high-energy multinary tellurides for potassium storage.

11.
Chem Sci ; 15(3): 1051-1060, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38239688

RESUMEN

Organic small-molecule compounds have become promising cathode materials for high-performance lithium-ion batteries (LIBs) due to their high theoretical capacity, efficient utilization of active sites, low cost, and sustainability. However, severe dissolution and poor electronic conductivity limit their further practical applications. Herein, we have synthesized an insoluble organic small molecule, ferrocenyl-3-(λ1-azazyl) pyrazinyl [2,3-f] [1,10] phenanthrolino-2-amine (FCPD), by grafting ferrocene onto pyrazino[2,3-f] [1,10] phenanthroline-2,3-diamine (PPD). The combination of ferrocene (p-type Fe2+ moiety) and PPD (n-type C[double bond, length as m-dash]N groups) in a bipolar manner endows the target FCPD cathode with an increased theoretical capacity and a wide voltage window. The highly conjugated π-π aromatic skeleton inside enhances FCPD's electron delocalization and promotes strong interaction between FCPD units. Additionally, the mesoporous structure within the FCPD can provide numerous electroactive sites, contact area, and ion diffusion channels. Benefiting from the bipolar feature, aromatic, and mesoporous structure, the FCPD cathode demonstrates a large capacity of 250 mA h g-1 at 0.1 A g-1, a long lifespan of 1000 cycles and a high-rate capability of 151 mA h g-1 at 5 A g-1 along with a wide voltage window (1.2-3.8 V). Additionally, in situ synchrotron FT-IR and ex situ XPS reveal its dual ion storage mechanism in depth. Our findings provide essential insights into exploring the molecular design of advanced organic small molecules.

12.
Small ; 20(15): e2308053, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38009478

RESUMEN

The urgent development of effective electrocatalysts for hydrogen evolution and hydrogen oxidation reaction (HER/HOR) is needed due to the sluggish alkaline hydrogen electrocatalysis. Here, an unusual face-centered cubic (fcc) Ru nanocrystal with favorable HER/HOR performance is offered. Guided by the lower calculated surface energy of fcc Ru than that of hcp Ru in NH3, the carbon-supported fcc Ru electrocatalyst is facilely synthesized in the NH3 reducing atmosphere. The specific HOR kinetic current density of fcc Ru can reach 23.4 mA cmPGM -2, which is around 20 and 21 times greater than that of hexagonal close-packed (hcp) Ru and Pt/C, respectively. Additionally, the HER specific activity is enhanced more than six times in fcc Ru electrocatalyst when compared to Pt/C. Experimental and theoretical analysis indicate that the phase transition from hcp Ru to fcc Ru can negatively shift the d band center, weaken the interaction between catalysts and key intermediates and therefore enhances the HER/HOR kinetics.

13.
Adv Mater ; 36(11): e2310623, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38088907

RESUMEN

The practical implementation of aqueous zinc-ion batteries (AZIBs) encounters challenges such as dendrite growth, parasitic reactions, and severe decay in battery performance under harsh environments. Here, a novel hydrated eutectic electrolyte (HEE) composed of Zn(ClO4 )2 ·6H2 O, ethylene glycol (EG), and InCl3 solution is introduced to effectively extend the lifespan of AZIBs over a wide temperature range from -50 to 50 °C. Molecular dynamics simulations and spectroscopy analysis demonstrate that the H2 O molecules are confined within the liquid eutectic network through dual-interaction, involving coordination with Zn2+ and hydrogen bonding with EG, thus weakening the activity of free water and extending the electrochemical window. Importantly, cryo-transmission electron microscopy and spectroscopy techniques reveal that HEE in situ forms a zincophobic/zincophilic bilayer interphase by the dissociation-reduction of eutectic molecules. Specifically, the zincophilic interphase reduces the energy barrier for Zn nucleation, promoting uniform Zn deposition, while the zincophobic interphase prevents active water from contacting the Zn surface, thus inhibiting the side reactions. Furthermore, the relationships between the structural evolution of the liquid eutectic network and interfacial chemistry at electrode/electrolyte interphase are further discussed in this work. The scalability of this design strategy can bring benefits to AZIBs operating over a wide temperature range.

14.
Small ; 20(22): e2308419, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38102103

RESUMEN

The unsatisfactory oxygen evolution reaction (OER) activity of IrO2 has intensively raised the cost and energy consumption of hydrogen generation from proton exchange membrane water electrolyzers. Here, the acidic OER activity of the rutile IrO2 is significantly enhanced by the incorporation of trivalent metals (e.g., Gd, Nd, and Pr) to increase the Ir-O covalency, while the high-valence (pentavalent or higher) metal incorporation decreases the Ir-O covalency resulting in worse OER activity. Experimental and theoretical analyses indicate that enhanced Ir-O covalency activates lattice oxygen and triggers lattice oxygen-mediated mechanism to enhance OER kinetics, which is verified by the finding of a linear relationship between the natural logarithm of intrinsic activity and Ir-O covalency described by charge transfer energy. By regulating the Ir-O covalency, the obtained Gd-IrO2-δ merely needs 260 mV of overpotential to reach 10 mA cm-2 and shows impressive stability during a 200-h test in 0.5 м H2SO4. This work provides an effective strategy for significantly enhancing the OER activity of the widely used IrO2 electrocatalysts through the rational regulation of Ir-O covalency.

15.
Artículo en Inglés | MEDLINE | ID: mdl-37874797

RESUMEN

Organic compounds exhibit great potential as sustainable, tailorable, and environmentally friendly electrode materials for rechargeable batteries. However, the intrinsic defects of organic electrodes, including solubility, low ionic conductivity, and restricted electroactivity sites, will inevitably decrease the cycling life and capacity. We herein designed and prepared nanostructured porous polymers (NPP) with a simple one-pot method to overcome the above defects. Theoretical calculations and experimental results demonstrate that the as-synthesized NPP exhibited low volume expansion, molecular-structural distortion, and a gradual function activation process during cycling, thus exhibiting superior, high, and durable lithium storage. The gradual molecular distortion during the lithium storage processes provides more redox-active sites for Li storage, increasing the Li-storage capacity. Ex situ spectrum studies reveal the redox reaction mechanism of Li storage and demonstrate a gradual activation process during the repeated charging/discharging until the full storage of 18 Li ions is achieved. Additionally, a real-time observation on the NPP anode by in situ transmission electron microscope reveals a slight volume expansion during the repeating lithiation and delithiation processes, ensuring its structural integrity during cycling. This quantitative work for high-durability lithium storage could be of immediate benefit for designing organic electrode materials.

16.
Chem Sci ; 14(37): 10147-10154, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37772126

RESUMEN

Batteries that are both high-energy-density and durable at sub-zero temperatures are highly desirable for deep space and subsea exploration and military defense applications. Our design incorporates a casting membrane technology to prepare a gallium indium liquid metal (LM)/fluoropolymer hybrid protective film on a lithium metal anode. The LM not only spontaneously forms a passivation alloy layer with lithium but also reduces the nucleation potential barrier and homogenizes the Li+ flux on the surface of the lithium anode. The fluoropolymer's polar functional groups (-C-F-) effectively induce targeted dispersion of gallium indium seeds, and the unique pit structure on the surface provides oriented sites for lithium plating. By implementing these strategies optimally, the protected lithium metal anode remains in operation at a current density of 20 mA cm-2 with an over-potential of about 50.4 mV after 500 h, and the full cells have a high capacity retention rate of up to 98.5% at a current density of 0.5 C after 100 cycles. Furthermore, the battery shows improved low temperature performance at -30 °C, validating the potential of the protective film to enable battery operation at sub-zero temperatures.

17.
Sports Med Health Sci ; 5(3): 196-204, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37753419

RESUMEN

During the Coronavirus disease (COVID-19), the physical activity of older adults is at a lower level. The study aimed to examine the effectiveness of aerobic dancing on physical fitness and cognitive function in older adults. We conducted a randomized controlled trial with 34 older adults who were assigned into an aerobic dancing group and a control group. Three dance sessions weekly for 60 â€‹min were scheduled for the aerobic dancing group for a total of 12 weeks. Physical fitness, blood pressure, lipids, glucose, cognitive function were assessed before and after the intervention. Baseline adjusted Analysis of Covariance (ANCOVA) was used to determine whether outcome variables varied between groups at pre-test and post-test. Effect size (Cohen's d) was calculated to determine the differences between groups from baseline to post-test. After 12 weeks, we found that the aerobic dancing group showed significant improvement in memory (portrait memory: F â€‹= â€‹10.45, p â€‹= â€‹0.003, d â€‹= â€‹1.18). The Limit of Stability (LOS) parameters in the aerobic dancing group displayed a significant increase after the intervention (right angle: F â€‹= â€‹5.90, p â€‹= â€‹0.022, d â€‹= â€‹0.60; right-anterior angle: F â€‹= â€‹4.23, p â€‹= â€‹0.049, d â€‹= â€‹0.12). Some beneficial effects were found on flexibility, grip strength, balance and subjective well-being (sit and reach: F â€‹= â€‹0.25, p â€‹= â€‹0.62, d â€‹= â€‹-0.40; grip strength: F â€‹= â€‹3.38, p â€‹= â€‹0.08, d â€‹= â€‹0.89; one-legged standing with eyes closed: F â€‹= â€‹1.26, p â€‹= â€‹0.27, d â€‹= â€‹0.50) in the aerobic dancing group. Aerobic dancing training was effective in improving memory and balance ability in older adults during the COVID-19 pandemic in China. In the future, aerobic dancing is a promising tool to encourage physical activity in older adults.

18.
Chem Sci ; 14(34): 9033-9040, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37655030

RESUMEN

Organic materials offer great potential as electrodes for batteries due to their high theoretical capacity, flexible structural design, and easily accessible materials. However, one significant drawback of organic electrode materials is their tendency to dissolve in the electrolyte. Resazurin sodium salt (RSS) has demonstrated remarkable charge/discharge performance characterized by a voltage plateau and high capacity when utilized as a cathode in aqueous zinc-ion batteries (AZIBs). Unfortunately, the solubility of RSS as a sodium salt continues to pose challenges in AZIBs. In this study, we introduce an RSS-containing organic compound, triresazurin-triazine (TRT), with a porous structure prepared by a desalinization method from the RSS and 2,4,6-trichloro-1,3,5-triazine (TCT). This process retained active groups (carbonyl and nitroxide radical) while generating a highly conjugated structure, which not only inhibits the dissolution in the electrolyte, but also improves the electrical conductivity, enabling TRT to have excellent electrochemical properties. When evaluated as a cathode for AZIBs, TRT exhibits a high reversible capacity of 180 mA h g-1, exceptional rate performance (78 mA h g-1 under 2 A g-1), and excellent cycling stability with 65 mA h g-1 at 500 mA g-1 after 1000 cycles.

19.
Nano Lett ; 23(11): 5187-5193, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37276263

RESUMEN

Intermetallic compounds, featuring atomically ordered structures, have emerged as a class of promising electrocatalysts for fuel cells. However, it remains a formidable challenge to controllably synthesize Pt-based intermetallics during the essential high-temperature annealing process as well as stabilize the nanoparticles (NPs) during the electrocatalytic process. Herein, we demonstrated a Ketjen black supported intermetallic Pt3Ti nanocatalyst coupled with amorphous TiOx species (Pt3Ti-TiOx/KB). The TiOx can not only confine Pt3Ti NPs during the synthesis and electrocatalytic process by a strong metal-oxide interaction but also promote the water dissociation for generating more OH species, thus facilitating the conversion of COad. The Pt3Ti-TiOx/KB showed a significantly enhanced mass activity (2.15 A mgPt-1) for the methanol oxidation reaction, compared with Pt3Ti/KB and Pt/C, and presented an impressively high mass activity retention (∼71%) after the durability test. This work provides an effective strategy of coupling Pt-based intermetallics with functional oxides for developing highly performed electrocatalysts.

20.
Inflammation ; 46(4): 1133-1143, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37046145

RESUMEN

Circadian disruption is involved in the progress of sepsis-induced cardiomyopathy (SICM), one of the leading causes of death in sepsis. The molecular mechanism remains ambiguous. In this study, LPS was used to build SICM model in H9c2 cell. The results suggested that LPS induced cytotoxicity via increasing ferroptosis over the time of course. After screening the expressions of six circadian genes, the circadian swing of Bmal1 was dramatically restrained by LPS in H9c2 cell of SIMC vitro model. PcDNA and siRNA were used to upregulate and downregulate Bmal1 and confirmed that Bmal1 inhibited LPS-triggered ferroptosis in H9c2 cells. Then, the results suggested that AKT/p53 pathway was restrained by LPS in H9c2 cell. Rescue test indicated that Bmal1 inhibited LPS-triggered ferroptosis via AKT/p53 pathway in H9c2 cells. In summary, our findings demonstrated that LPS induced cytotoxicity via increasing ferroptosis over the time of course in H9c2 cells and Bmal1 inhibited this toxicity of LPS via AKT/p53 pathway. Although further studies are needed, our findings may contribute to a new insight to mechanism of SICM.


Asunto(s)
Ferroptosis , Lesiones Cardíacas , Sepsis , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Lipopolisacáridos/farmacología , Proteína p53 Supresora de Tumor , Ritmo Circadiano/fisiología , Sepsis/complicaciones
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