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1.
Nat Commun ; 15(1): 3325, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637537

RESUMEN

The effective flow of electrons through bulk electrodes is crucial for achieving high-performance batteries, although the poor conductivity of homocyclic sulfur molecules results in high barriers against the passage of electrons through electrode structures. This phenomenon causes incomplete reactions and the formation of metastable products. To enhance the performance of the electrode, it is important to place substitutable electrification units to accelerate the cleavage of sulfur molecules and increase the selectivity of stable products during charging and discharging. Herein, we develop a single-atom-charging strategy to address the electron transport issues in bulk sulfur electrodes. The establishment of the synergistic interaction between the adsorption model and electronic transfer helps us achieve a high level of selectivity towards the desirable short-chain sodium polysulfides during the practical battery test. These finding indicates that the atomic manganese sites have an enhanced ability to capture and donate electrons. Additionally, the charge transfer process facilitates the rearrangement of sodium ions, thereby accelerating the kinetics of the sodium ions through the electrostatic force. These combined effects improve pathway selectivity and conversion to stable products during the redox process, leading to superior electrochemical performance for room temperature sodium-sulfur batteries.

2.
Angew Chem Int Ed Engl ; : e202405750, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38660918

RESUMEN

The high energy density and cost-effectiveness of chloride-ion batteries (CIBs) make them promising alternatives to lithium-ion batteries. However, the development of CIBs is greatly restricted by the lack of compatible electrolytes to support cost-effective anodes. Herein, we present a rationally designed solid polycationic electrolyte (SPE) to enable room-temperature chloride-ion batteries utilizing aluminum (Al) metal as an anode. This SPE endows the CIB configuration with improved air stability and safety (i.e. free of flammability and liquid leakage). A high ionic conductivity (1.3×10-2 S cm-1 at 25 °C) has been achieved by the well-tailored solvation structure of the SPE. Meanwhile, the solid polycationic electrolyte ensures stable electrodes|electrolyte interfaces, which effectively inhibit the growth of dendrites on the Al anodes and degradation of the FeOCl cathodes. The Al|SPE|FeOCl chloride-ion batteries showcased a high discharge capacity around 250 mAh g-1 (based on the cathodes) and extended lifespan. Our electrolyte design opens a new avenue for developing low-cost chloride-ion batteries.

3.
Small ; : e2401957, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682730

RESUMEN

Prussian blue analogues (PBAs) have emerged as highly promising cathode materials for sodium-ion batteries (SIBs) due to their affordability, facile synthesis, porous framework, and high theoretical capacity. Despite their considerable potential, practical applications of PBAs face significant challenges that limit their performance. This review offers a comprehensive retrospective analysis of PBAs' development history as cathode materials, delving into their reaction mechanisms, including charge compensation and ion diffusion mechanisms. Furthermore, to overcome these challenges, a range of improvement strategies are proposed, encompassing modifications in synthesis techniques and enhancements in structural stability. Finally, the commercial viability of PBAs is examined, alongside discussions on advanced synthesis methods and existing concerns regarding cost and safety, aiming to foster ongoing advancements of PBAs for practical SIBs.

4.
Chem Rev ; 124(6): 3494-3589, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38478597

RESUMEN

The renewable energy industry demands rechargeable batteries that can be manufactured at low cost using abundant resources while offering high energy density, good safety, wide operating temperature windows, and long lifespans. Utilizing fluorine chemistry to redesign battery configurations/components is considered a critical strategy to fulfill these requirements due to the natural abundance, robust bond strength, and extraordinary electronegativity of fluorine and the high free energy of fluoride formation, which enables the fluorinated components with cost effectiveness, nonflammability, and intrinsic stability. In particular, fluorinated materials and electrode|electrolyte interphases have been demonstrated to significantly affect reaction reversibility/kinetics, safety, and temperature tolerance of rechargeable batteries. However, the underlining principles governing material design and the mechanistic insights of interphases at the atomic level have been largely overlooked. This review covers a wide range of topics from the exploration of fluorine-containing electrodes, fluorinated electrolyte constituents, and other fluorinated battery components for metal-ion shuttle batteries to constructing fluoride-ion batteries, dual-ion batteries, and other new chemistries. In doing so, this review aims to provide a comprehensive understanding of the structure-property interactions, the features of fluorinated interphases, and cutting-edge techniques for elucidating the role of fluorine chemistry in rechargeable batteries. Further, we present current challenges and promising strategies for employing fluorine chemistry, aiming to advance the electrochemical performance, wide temperature operation, and safety attributes of rechargeable batteries.

5.
Chem Soc Rev ; 53(8): 3829-3895, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38436202

RESUMEN

Subnanometer pores/channels (SNPCs) play crucial roles in regulating electrochemical redox reactions for rechargeable batteries. The delicately designed and tailored porous structure of SNPCs not only provides ample space for ion storage but also facilitates efficient ion diffusion within the electrodes in batteries, which can greatly improve the electrochemical performance. However, due to current technological limitations, it is challenging to synthesize and control the quality, storage, and transport of nanopores at the subnanometer scale, as well as to understand the relationship between SNPCs and performances. In this review, we systematically classify and summarize materials with SNPCs from a structural perspective, dividing them into one-dimensional (1D) SNPCs, two-dimensional (2D) SNPCs, and three-dimensional (3D) SNPCs. We also unveil the unique physicochemical properties of SNPCs and analyse electrochemical couplings in SNPCs for rechargeable batteries, including cathodes, anodes, electrolytes, and functional materials. Finally, we discuss the challenges that SNPCs may face in electrochemical reactions in batteries and propose future research directions.

6.
Talanta ; 270: 125617, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38176250

RESUMEN

As a novel class of stationary phase materials, covalent organic frameworks (COFs) have shown great promise in open-tubular capillary electrochromatography. However, the current preparation of COFs coating capillaries heavily relies on tedious and time-consuming covalent bond methods. In this work, a novel, simple and rapid adsorption method was developed for fabrication of TPB-DMTP COF (fabricated from 1,3,5-tris(4-aminophenyl)benzene (TPB) and 2,5-dimethoxyterephthalaldehyde (DMTP)) coated capillary. Due to the crystallization process of the COF is greatly shortened because pre-modification capillary does not require silane coupling agent, this method enables the rapid preparation of COFs-coated capillaries. The organic molecular building units only need 25 min to form a stable COFs coating on the inner wall of a capillary by this method. To our knowledge, this is the shortest method for preparing COFs coated capillary up to now. The performance of the TPB-DMTP COF coated capillary was evaluated by using phthalate esters as model analytes. The results demonstrated that the TPB-DMTP COF coated capillary has excellent repeatability and stability. The relative standard deviations (RSDs) of the analyte's retention time of intra-day, inter-day and column-to-column were in the range of 0.05 %-0.27 %, 0.31 %-0.63 % and 0.31 %-0.88 %, respectively. And, no significant changes were observed in separation efficiency and retention time after over 200 runs. Finally, the TPB-DMTP COF coated capillary was applied for the determination of phthalates in marketed plastic bag and the recovery ranged from 88.0 % to 114.0 %.

7.
Gene ; 900: 148137, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38184018

RESUMEN

Phosphodiesterase 9A (PDE9A) plays a crucial role in activating the cGMP-dependent signaling pathway and may have important effects on the growth and development of the gastrointestinal tract in Hu sheep. In this study, we analyzed the single nucleotide polymorphisms of PDE9A in 988 Hu sheep and their correlation with growth performance, feed efficiency, and gastrointestinal development. Additionally, we examined the expression level of different PDE9A genotypes in the gastrointestinal tract of Hu sheep by using fluorescence quantitative PCR. The results revealed a moderate level of polymorphism (0.25 < PIC < 0.50) at the g.286248617 T > C mutation site located in the first intron of PDE9A in Hu sheep, with three genotypes: CC, CT, and TT. The weights of the omasum, colon, and cecum were significantly greater in the CC genotype than in the TT genotype (P < 0.05), and the expression level of PDE9A in the tissues of the rumen, ileum, cecum, and colon was notably lower in the CC genotype individuals (P < 0.05). These findings suggest that the polymorphism of PDE9A affects the weight of the stomach, colon, and cecum in Hu sheep through expression regulation. Overall, the results of this study suggest that the g.286248617 T > C mutation site in the first intron of PDE9A can serve as a potential molecular marker for breeding practices related to the gastrointestinal weight of Hu sheep.


Asunto(s)
Cruzamiento , Polimorfismo de Nucleótido Simple , Animales , 3',5'-AMP Cíclico Fosfodiesterasas/genética , Tracto Gastrointestinal , Genotipo , Ovinos/genética
8.
Angew Chem Int Ed Engl ; 63(4): e202315947, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38059770

RESUMEN

Osmotic power, a clean energy source, can be harvested from the salinity difference between seawater and river water. However, the output power densities are hampered by the trade-off between ion selectivity and ion permeability. Here we propose an effective strategy of double angstrom-scale confinement (DAC) to design ion-permselective channels with enhanced ion selectivity and permeability simultaneously. The fabricated DAC-Ti0.87 O2 membranes possess both Ti atomic vacancies and an interlayer free spacing of ≈2.2 Å, which not only generates a profitable confinement effect for Na+ ions to enable high ion selectivity but also induces a strong interaction with Na+ ions to benefit high ion permeability. Consequently, when applied to osmotic power generation, the DAC-Ti0.87 O2 membranes achieved an ultrahigh power density of 17.8 W m-2 by mixing 0.5/0.01 M NaCl solution and up to 114.2 W m-2 with a 500-fold salinity gradient, far exceeding all the reported macroscopic-scale membranes. This work highlights the potential of the construction of DAC ion-permselective channels for two-dimensional materials in high-performance nanofluidic energy systems.

9.
Adv Mater ; 36(7): e2308275, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37852011

RESUMEN

Lithium garnets are considered as promising solid-state electrolytes for next-generation solid-state Li metal batteries (SSLBs). However, the Li intrusion driven by external stack pressure triggers premature of Li metal batteries. Herein, for the first time, an in situ constructed interfacial shield is reported to efficiently inhibit the pressure-induced Li intrusion in SSLBs. Theoretical modeling and experimental investigations reveal that high-hardness metallic Mo nanocrystals inside the shield effectively suppress Li dendrite growth without alloy hardening-derived interfacial contact deterioration. Meanwhile the electrically insulated Li2 S as a shield component considerably promotes interfacial wettability and hinders Li dendrite penetration into the bulk of garnet electrolyte. Interfacial shield-protected Li6.4 La3 Zr1.4 Ta0.6 O12 (LLZTO)-based cells exhibit significantly enhanced cyclability without short circuits under conventional pressures of ≈0.2 MPa and even at high pressure of up to 70 MPa; which is the highest endurable stack pressure reported for SSLBs using garnet electrolytes. These key findings are expected to promote the wide-pressure-range applications of SSLBs.

10.
Adv Mater ; 36(3): e2309726, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37962322

RESUMEN

Aqueous Zn metal batteries are considered as competitive candidates for next-generation energy storage systems due to their excellent safety, low cost, and environmental friendliness. However, the inevitable dendrite growth, severe hydrogen evolution, surface passivation, and sluggish reaction kinetics of Zn metal anodes hinder the practical application of Zn metal batteries. Detailed summaries and prospects have been reported focusing on the research progress and challenges of Zn metal anodes, including electrolyte engineering, electrode structure design, and surface modification. However, the essential electrical mechanisms that significantly influence Zn2+ ions migration and deposition behaviors have not been reviewed yet. Herein, in this review, the regulation mechanisms of electrical-related electrostatic repulsive/attractive interactions on Zn2+ ions migration, desolvation, and deposition behaviors are systematically discussed. Meanwhile, electric field regulation strategies to promote the Zn2+ ions diffusion and uniform Zn deposition are comprehensively reviewed, including enhancing and homogenizing electric field intensity inside the batteries and adding external magnetic/pressure/thermal field to couple with the electric field. Finally, future perspectives on the research directions of the electrical-related strategies for building better Zn metal batteries in practical applications are offered.

11.
Proc Natl Acad Sci U S A ; 120(52): e2307477120, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38134195

RESUMEN

Potassium-ion batteries (PIBs) have attracted ever-increasing interest due to the abundant potassium resources and low cost, which are considered a sustainable energy storage technology. However, the graphite anodes employed in PIBs suffer from low capacity and sluggish reaction kinetics caused by the large radius of potassium ions. Herein, we report nitrogen-doped, defect-rich hollow carbon nanospheres with contact curved interfaces (CCIs) on carbon nanotubes (CNTs), namely CCI-CNS/CNT, to boost both electron transfer and potassium-ion adsorption. Density functional theory calculations validate that engineering CCIs significantly augments the electronic state near the Fermi level, thus promoting electron transfer. In addition, the CCIs exhibit a pronounced affinity for potassium ions, promoting their adsorption and subsequently benefiting potassium storage. As a result, the rationally designed CCI-CNS/CNT anode shows remarkable cyclic stability and rate capability. This work provides a strategy for enhancing the potassium storage performance of carbonaceous materials through CCI engineering, which can be further extended to other battery systems.

12.
Nanomicro Lett ; 16(1): 12, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37947874

RESUMEN

Lithium-sulfur (Li-S) batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost. Nevertheless, the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value. Many methods were proposed for inhibiting the shuttle effect of polysulfide, improving corresponding redox kinetics and enhancing the integral performance of Li-S batteries. Here, we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li-S batteries. First, the electrochemical principles/mechanism and origin of the shuttle effect are described in detail. Moreover, the efficient strategies, including boosting the sulfur conversion rate of sulfur, confining sulfur or lithium polysulfides (LPS) within cathode host, confining LPS in the shield layer, and preventing LPS from contacting the anode, will be discussed to suppress the shuttle effect. Then, recent advances in inhibition of shuttle effect in cathode, electrolyte, separator, and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li-S batteries. Finally, we present prospects for inhibition of the LPS shuttle and potential development directions in Li-S batteries.

13.
Animals (Basel) ; 13(11)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37889672

RESUMEN

Although early feeding strategies influence intestinal development, the effects of milk replacer (MR) feeding level on intestinal structure and functional development and underlying regulatory mechanisms remain unclear. In this study, 14 male Hu lambs were fed MR at 2% or 4% of their average body weight and weaned at 35 days of age. The MR was produced by the Institute of Feed Research of the Chinese Academy of Agricultural Sciences, and it contains 96.91% dry matter, 23.22% protein, and 13.20% fat. Jejunal tissues were assessed by RNA-seq for differences in the gene expression of lambs at 49 days of age; regulatory pathways and mechanisms of the effects of early nutrition on intestinal function and development were analyzed, along with growth performance, feed intake, jejunal histomorphology, and digestive enzyme activities. Increasing MR- feeding levels increased dry matter intake and daily gain before weaning, as well as lactase, amylase, lipase, trypsin, and chymotrypsin activities and intestinal villus length and muscular thickness. Overall, 1179 differentially expressed genes were identified, which were enriched in nutrient metabolism, coagulation cascades, and other pathways. Further, intensive MR feeding affected insulin sensitivity to reduce excessive glucose interception by intestinal tissues to ensure adequate absorbed glucose release into the portal circulation and promoted lipid and protein degradation in intestinal tissues to meet the energy demand of intestinal cells by regulating AHSG, IGFBP1, MGAT2, ITIH, and CYP2E1 expression.

14.
Se Pu ; 41(10): 835-842, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37875406

RESUMEN

Capillary electrochromatography (CEC) has received increased attention from the academic community because it combines the excellent selectivity of high performance liquid chromatography (HPLC) and the high efficiency of capillary electrophoresis (CE). Selecting the most appropriate stationary phase material is crucial to achieve better separation effects in CEC. In recent years, a considerable number of materials, such as graphene oxide, proteins, metal organic frameworks, and covalent organic frameworks (COFs), have been widely used as stationary phases in CEC to further improve its separation performance and extend its scope of potential applications. Among these materials, COFs have shown great application prospects in CEC owing to their unique properties, which include high porosity, large surface area, excellent stability, tunable pore size, and high designability of the framework structure. This review systematically summarizes published papers on the development and application of COFs in CEC from 2016 to 2023. First, two COF-based capillary columns (i. e., open-tube CEC columns and monolithic CEC columns) and their preparation methods are introduced. Second, the applications of CEC based on COF stationary phases in the separation of environmental endocrine disruptors, pesticides, aromatic compounds, amino acids, and drugs, particularly chiral drugs, are systematically summarized. The separation mechanism of CEC based on COF stationary phases is also introduced. At present, the good separation ability of COF-based CEC is mainly attributed to two factors: 1) The size exclusion effect of the pores of the COF stationary phase. Because of differences in the sizes of their organic molecular building units and side chains, COFs have varying pore sizes and topological structures. Thus, target analytes smaller than the pores of the COFs can enter the frameworks and interact with them during separation. On the other hand, target analytes larger than the pores of the COFs cannot enter the frameworks and interact with them during separation; thus, they can be separated. 2) The interactions between the target analytes and side chains (e. g., hydrophobic interactions, hydrogen bonding, π-π interactions, etc.) of the COFs. Since COFs usually contain alkyl side chains, aromatic structures, and oxygen and/or nitrogen atoms with high electronegativity, various interactions could occur between the COFs and target analytes. Finally, directions for the future development and strategic application of CEC based on COF stationary phases are proposed. We believe that future research in CEC based on COF stationary phases should focus on the following aspects: 1) The use of cheminformatics to design and construct COFs to improve the efficiency of COF capillary column preparation; 2) the development of milder methods to synthesize COFs that can meet the requirements of high performance COF capillary columns; and 3) in-depth research to explore the separation mechanism of CEC based on COF stationary phases to provide theoretical guidance for developing CEC methods suitable for the separation and analysis of complex samples.

15.
Angew Chem Int Ed Engl ; 62(50): e202306904, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37650332

RESUMEN

The exploration of cathode and anode materials that enable reversible storage of mono and multivalent cations has driven extensive research on organic compounds. In this regard, polyimide (PI)-based electrodes have emerged as a promising avenue for the development of post-lithium energy storage systems. This review article provides a comprehensive summary of the syntheses, characterizations, and applications of PI compounds as electrode materials capable of hosting a wide range of cations. Furthermore, the review also delves into the advancements in PI based solid state batteries, PI-based separators, current collectors, and their effectiveness as polymeric binders. By highlighting the key findings in these areas, this review aims at contributing to the understanding and advancement of PI-based structures paving the way for the next generation of energy storage systems.

16.
Nanomicro Lett ; 15(1): 185, 2023 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-37515746

RESUMEN

The electrochemical oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are fundamental processes in a range of energy conversion devices such as fuel cells and metal-air batteries. ORR and OER both have significant activation barriers, which severely limit the overall performance of energy conversion devices that utilize ORR/OER. Meanwhile, ORR is another very important electrochemical reaction involving oxygen that has been widely investigated. ORR occurs in aqueous solutions via two pathways: the direct 4-electron reduction or 2-electron reduction pathways from O2 to water (H2O) or from O2 to hydrogen peroxide (H2O2). Noble metal electrocatalysts are often used to catalyze OER and ORR, despite the fact that noble metal electrocatalysts have certain intrinsic limitations, such as low storage. Thus, it is urgent to develop more active and stable low-cost electrocatalysts, especially for severe environments (e.g., acidic media). Theoretically, an ideal oxygen electrocatalyst should provide adequate binding to oxygen species. Transition metals not belonging to the platinum group metal-based oxides are a low-cost substance that could give a d orbital for oxygen species binding. As a result, transition metal oxides are regarded as a substitute for typical precious metal oxygen electrocatalysts. However, the development of oxide catalysts for oxygen reduction and oxygen evolution reactions still faces significant challenges, e.g., catalytic activity, stability, cost, and reaction mechanism. We discuss the fundamental principles underlying the design of oxide catalysts, including the influence of crystal structure, and electronic structure on their performance. We also discuss the challenges associated with developing oxide catalysts and the potential strategies to overcome these challenges.

17.
Sci Bull (Beijing) ; 68(16): 1819-1842, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37516661

RESUMEN

Magnesium-ion batteries (MIBs) are considered strong candidates for next-generation energy-storage systems owing to their high theoretical capacity, divalent nature and the natural abundancy of magnesium (Mg) resources on Earth. However, the development of MIBs has been mainly limited by the incompatibility of Mg anodes with several Mg salts and conventional organic-liquid electrolytes. Therefore, one major challenge faced by MIBs technology lies on developing safe electrolytes, which demonstrate appropriate electrochemical voltage window and compatibility with Mg anode. This review discusses the development of MIBs from the point-of-view of the electrolyte syntheses. A systematic assessment of promising electrolyte design strategies is proposed including liquid and solid-state electrolytes. Liquid-based electrolytes have been largely explored and can be categorized by solvent-type: organic solvent, aqueous solvent, and ionic-liquids. Organic-liquid electrolytes usually present high electrochemical and chemical stability but are rather dangerous, while aqueous electrolytes present high ionic conductivity and eco-friendliness but narrow electrochemical stability window. Some ionic-liquid electrolytes have proved outstanding performance but are fairly expensive. As alternative to liquid electrolytes, solid-state electrolytes are increasingly attractive to increase energy density and safety. However, improving the ionic conductivity of Mg ions in these types of electrolytes is extremely challenging. We believe that this comprehensive review will enable researchers to rapidly grasp the problems faced by electrolytes for MIBs and the electrolyte design strategies proposed to this date.

18.
Angew Chem Int Ed Engl ; 62(36): e202308349, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37452696

RESUMEN

Electrocatalysts for highly efficient oxygen reduction reaction (ORR) are crucial for energy conversion and storage devices. Single-atom catalysts with maximized metal utilization and altered electronic structure are the most promising alternatives to replace current benchmark precious metals. However, the atomic level understanding of the functional role for each species at the anchoring sites is still unclear and poorly elucidated. Herein, we report Fe single atom catalysts with the sulfur and oxygen functional groups near the atomically dispersed metal centers (Fe1/NSOC) for highly efficient ORR. The Fe1/NSOC delivers a half-wave potential of 0.92 V vs. RHE, which is much better than those of commercial Pt/C (0.88 V), Fe single atoms on N-doped carbon (Fe1/NC, 0.89 V) and most reported nonprecious metal catalysts. The spectroscopic measurements reveal that the presence of sulfur group induces the formation of epoxy groups near the FeN4S2 centers, which not only modulate the electronic structure of Fe single atoms but also participate the catalytic process to improve the kinetics. The density functional theory calculations demonstrate the existence of sulfur and epoxy group engineer the charges of Fe reactive center and facilitate the reductive release of OH* (rate-limiting step), thus boosting the overall oxygen reduction efficiency.

19.
Small ; 19(41): e2302639, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37309285

RESUMEN

Rational design and development of highly efficient hydrogen evolution reaction (HER) electrocatalysts is of great significance for the development of green water electrolysis hydrogen production technology. Ru-engineered 1D PtCo-Ptrich nanowires (Ru-Ptrich Co NWs) are fabricated by a facile electrodeposition method. The rich Pt surface on 1D Pt3 Co contributes to the fully exposed active sites and enhanced intrinsic catalytic activity (co-engineered by Ru and Co atoms) for HER. The incorporation of Ru atoms can not only accelerate the water dissociation in alkaline condition to provide sufficient H* but also modulate the electronic structure of Pt to achieve optimized H* adsorption energy. As a result, Ru-Ptrich Co NWs have exhibited ultralow HER overpotentials (η) of 8 and 112 mV to achieve current densities of 10 and 100 mA cm-2 in 1 m KOH, respectively, which far exceed those of commercial Pt/C catalyst (η10  = 29 mV, η100  = 206 mV). Density functional theory (DFT) calculations further demonstrate that the incorporated Ru atoms possess strong water adsorption capacity (-0.52 vs -0.12 eV for Pt), facilitating water dissociation. The Pt atoms in the outermost Pt-rich skin of Ru-Ptrich Co NWs achieve optimized H* adsorption free energy (ΔGH* ) of -0.08 eV, boosting hydrogen generation.

20.
Prim Care Diabetes ; 17(4): 287-308, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37127452

RESUMEN

PURPOSE: Dietary interventions are the cornerstone of gestational diabetes mellitus (GDM) treatment. This study aimed to evaluate the effects of dietary patterns during pregnancy on birth outcomes and glucose parameters in women with GDM. METHODS: PubMed, Embase, and The CoChrane Library were searched from the time of database creation to November 30, 2021, along with manual searches. Data analyses were performed using Stata 15.4 software. RESULTS: From 2461 studies, 27 RCTs involving 1923 women were eligible. The pooled results showed that dietary pattern interventions during pregnancy reduced birth weight (WMD: -0.14 kg; 95% CI: -0.24, -0.00), hemoglobin A1 C (HbA1 C) (WMD: -0.19, 95% CI: -0.34, -0.05), and macrosomia incidence (RR 0.65 [95% CI 0.48, 0.88]). Low glycemic index (GI) diet reduced macrosomia incidence (RR 0.31 [95% CI 0.11, 0.93]) and fasting plasma glucose (FPG) levels (WMD: -0.10 mmol/L; 95% CI: -0.14, -0.05); a low carbohydrate (CHO) diet reduced large for gestational age (LGA) incidence (RR 0.33 [95% CI 0.13, 0.82]) and HbA1 C (WMD: -0.32; 95% CI: -0.51, -0.14); dietary approaches to stop hypertension (DASH) diet reduced birth weight (WMD:-0.59 kg; 95% CI: -0.64, -0.55), insulin use (RR 0.31 [95% CI 0.18, 0.56), macrosomia incidence (RR 0.12 [95% CI 0.03, 0.50]), and cesarean sections incidence (RR 0.57 [95% CI 0.40, 0.82]). CONCLUSION: Dietary patterns during pregnancy can improve certain birth outcomes and glycemic parameters. Due to limitations in the quality and number of included studies, the above findings still need to be validated by further randomized controlled trials with high quality and large samples.


Asunto(s)
Diabetes Gestacional , Embarazo , Femenino , Humanos , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiología , Diabetes Gestacional/terapia , Macrosomía Fetal/diagnóstico , Macrosomía Fetal/epidemiología , Macrosomía Fetal/prevención & control , Peso al Nacer , Glucosa , Dieta/efectos adversos
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