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1.
Nature ; 621(7977): 75-81, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37673990

RESUMO

Benefiting from high energy density (2,600 Wh kg-1) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems1-4. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides5-7, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution8-10. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li2S2 and Li2S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li+ and Sn2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. The collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

2.
Nature ; 579(7797): 118-122, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103178

RESUMO

It has long been assumed that lifespan and healthspan correlate strongly, yet the two can be clearly dissociated1-6. Although there has been a global increase in human life expectancy, increasing longevity is rarely accompanied by an extended healthspan4,7. Thus, understanding the origin of healthy behaviours in old people remains an important and challenging task. Here we report a conserved epigenetic mechanism underlying healthy ageing. Through genome-wide RNA-interference-based screening of genes that regulate behavioural deterioration in ageing Caenorhabditis elegans, we identify 59 genes as potential modulators of the rate of age-related behavioural deterioration. Among these modulators, we found that a neuronal epigenetic reader, BAZ-2, and a neuronal histone 3 lysine 9 methyltransferase, SET-6, accelerate behavioural deterioration in C. elegans by reducing mitochondrial function, repressing the expression of nuclear-encoded mitochondrial proteins. This mechanism is conserved in cultured mouse neurons and human cells. Examination of human databases8,9 shows that expression of the human orthologues of these C. elegans regulators, BAZ2B and EHMT1, in the frontal cortex increases with age and correlates positively with the progression of Alzheimer's disease. Furthermore, ablation of Baz2b, the mouse orthologue of BAZ-2, attenuates age-dependent body-weight gain and prevents cognitive decline in ageing mice. Thus our genome-wide RNA-interference screen in C. elegans has unravelled conserved epigenetic negative regulators of ageing, suggesting possible ways to achieve healthy ageing.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Epigênese Genética , Envelhecimento Saudável/genética , Histona-Lisina N-Metiltransferase/metabolismo , Fatores Genéricos de Transcrição/metabolismo , Envelhecimento/genética , Animais , Proteínas de Caenorhabditis elegans/genética , Cognição , Disfunção Cognitiva , Histona-Lisina N-Metiltransferase/deficiência , Histona-Lisina N-Metiltransferase/genética , Histonas/química , Histonas/metabolismo , Humanos , Longevidade/genética , Lisina/metabolismo , Masculino , Memória , Metilação , Camundongos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Proteínas/genética , Interferência de RNA , Aprendizagem Espacial , Fatores Genéricos de Transcrição/deficiência , Fatores Genéricos de Transcrição/genética
3.
Nano Lett ; 24(32): 9839-9845, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39087826

RESUMO

Hard carbon (HC) is a promising anode candidate for Na-ion batteries (NIBs) because of its excellent Na-storage performance, abundance, and low cost. However, a precise understanding of its Na-storage behavior remains elusive. Herein, based on the D2O/H2SO4-based TMS results collected on charged/discharged state HC electrodes, detailed Na-storage mechanisms (the Na-storage states and active sites in different voltage regions), specific SEI dynamic evolution process (formation, rupture, regeneration and loss), and irreversible capacity contribution (dead Na0, NaH, etc.) were elucidated. Moreover, by employing the online electrochemical mass spectrometry (OEMS) to monitor the gassing behavior of HC-Na half-cell during the overdischarging process, a surprising rehydrogen evolution reaction (re-HER) process at around 0.02 V vs Na+/Na was identified, indicating the occurrence of Na-plating above 0 V vs Na+/Na. Additionally, the typical fluorine ethylene carbonate (FEC) additive was demonstrated to reduce the accumulation of dead Na0 and inhibit the re-HER process triggered by plated Na.

4.
Nano Lett ; 24(34): 10642-10649, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39158134

RESUMO

CO poisoning in Pt-based anode catalysts significantly hampers the proton exchange membrane fuel cell (PEMFC) performance. Despite great advances in CO-tolerant catalysts, their effectiveness is often limited to fundamental three-electrode systems, which is inadequate for practical PEMFC applications. Herein, we present a straightforward thermal oxidation strategy for constructing a Ru oxide blocking layer on commercial PtRu/C through a one-step Ru-segregation-and-oxidation process. The resulting 0.7 nm thick Ru oxide layer effectively inhibits CO adsorption while maintaining hydrogen oxidation activity. PtRu@RuO2/C demonstrates exceptional CO tolerance, enduring 1% CO in rotating disk electrode tests, an ∼10-fold improvement compared to that of PtRu/C. Crucially, it retains high HOR activity and CO tolerance in PEMFC, with negligible polarization curve loss in the presence of 100 ppm CO. Notably, 85% HOR activity is retained after a 4 h stability test. This enhancement contributes to the Ru oxide layer decelerating CO adsorption kinetics, rather than promoting CO oxidation via the classic bifunctional mechanism.

5.
J Am Chem Soc ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39197103

RESUMO

Nitrate (NO3-) in wastewater poses a serious threat to human health and the ecological environment. The electrocatalytic NO3- reduction to ammonia (NH3) reaction (NO3-RR) emerges as a promising carbon-free energy route for enabling NO3- removal and sustainable NH3 synthesis. However, it remains a challenge to achieve high Faraday efficiencies at a wide potential window due to the complex multiple-electron reduction process. Herein, spatially separated dual-metal tandem electrocatalysts made of a nitrogen-doped ordered mesoporous carbon support with ultrasmall and high-content Cu nanoparticles encapsulated inside and large and low-content Ru nanoparticles dispersed on the external surface (denoted as Ru/Cu@NOMC) are designed. In electrocatalytic NO3-RR, the Cu sites can quickly convert NO3- to adsorbed NO2- (*NO2-), while the Ru sites can efficiently produce active hydrogen (*H) to enhance the kinetics of converting *NO2- to NH3 on the Cu sites. Due to the synergistic effect between the Cu and Ru sites, Ru/Cu@NOMC exhibits a maximum NH3 Faradaic efficiency (FENH3) of approximately 100% at -0.1 V vs reversible hydrogen electrode (RHE) and a high NH3 yield rate of 1267 mmol gcat-1 h-1 at -0.5 V vs RHE. Finite element method (FEM) simulation and electrochemical in situ Raman spectroscopy revealed that the mesoporous framework can enhance the intermediate concentration due to the in situ confinement effect. Thanks to the Cu-Ru synergistic effect and the mesopore confinement effect, a wide potential window of approximately 500 mV for FENH3 over 90% and a superior stability for NH3 production over 156 h can be achieved on the Ru/Cu@NOMC catalyst.

6.
J Am Chem Soc ; 146(25): 17103-17113, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38869216

RESUMO

Understanding the interfacial hydrogen evolution reaction (HER) is crucial to regulate the electrochemical behavior in aqueous zinc batteries. However, the mechanism of HER related to solvation chemistry remains elusive, especially the time-dependent dynamic evolution of the hydrogen bond (H-bond) under an electric field. Herein, we combine in situ spectroscopy with molecular dynamics simulation to unravel the dynamic evolution of the interfacial solvation structure. We find two critical change processes involving Zn-electroplating/stripping, including the initial electric double layer establishment to form an H2O-rich interface (abrupt change) and the subsequent dynamic evolution of an H-bond (gradual change). Moreover, the number of H-bonds increases, and their strength weakens in comparison with the bulk electrolyte under bias potential during Zn2+ desolvation, forming a diluted interface, resulting in massive hydrogen production. On the contrary, a concentrated interface (H-bond number decreases and strength enhances) is formed and produces a small amount of hydrogen during Zn2+ solvation. The insights on the above results contribute to deciphering the H-bond evolution with competition/corrosion HER during Zn-electroplating/stripping and clarifying the essence of electrochemical window widened and HER suppression by high concentration. This work presents a new strategy for aqueous electrolyte regulation by benchmarking the abrupt change of the interfacial state under an electric field as a zinc performance-enhancement criterion.

7.
J Am Chem Soc ; 146(7): 4557-4569, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38345667

RESUMO

Intelligent utilization of the anionic redox reaction (ARR) in Li-rich cathodes is an advanced strategy for the practical implementation of next-generation high-energy-density rechargeable batteries. However, due to the intrinsic complexity of ARR (e.g., nucleophilic attacks), the instability of the cathode-electrolyte interphase (CEI) on a Li-rich cathode presents more challenges than typical high-voltage cathodes. Here, we manipulate CEI interfacial engineering by introducing an all-fluorinated electrolyte and exploiting its interaction with the nucleophilic attack to construct a gradient CEI containing a pair of fluorinated layers on a Li-rich cathode, delivering enhanced interfacial stability. Negative/detrimental nucleophilic electrolyte decomposition has been efficiently evolved to further reinforce CEI fabrication, resulting in the construction of LiF-based indurated outer shield and fluorinated polymer-based flexible inner sheaths. Gradient interphase engineering dramatically improved the capacity retention of the Li-rich cathode from 43 to 71% after 800 cycles and achieved superior cycling stability in anode-free and pouch-type full cells (98.8% capacity retention, 220 cycles), respectively.

8.
Anal Chem ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39185581

RESUMO

The spatial constraints imposed by the DNA structure have significant implications for the walking efficiency of three-dimensional DNA walkers. However, accurately quantifying and manipulating steric hindrance remains a challenging task. This study presents a steric hindrance-controlled DNA walker utilizing an enzymatic strand displacement amplification (ESDA) strategy for detecting microRNA-21 (miR-21) with tunable dynamic range and sensitivity. The steric hindrance of the DNA walker was precisely manipulated by varying the length of empty bases from 6.5 Što 27.4 Šat the end of the track strand and adjusting the volumetric dimensions of the hairpin structure from 9.13 nm3 to 26.2 nm3 at the terminus of the single-foot DNA walking strand. This method demonstrated a tunable limit of detection for miR-21 ranging from 3.6 aM to 35.6 nM, along with a dynamic range from ∼100-fold to ∼166 000-fold. Impressively, it exhibited successful identification of cancer cells and clinical serum samples with high miR-21 expression. The proposed novel strategy not only enables tunable detection of miRNA through the regulation of steric hindrance but also achieves accurate and quantitative analysis of the steric hindrance effect, promising broader applications in personalized medicine, early disease detection, and drug development.

9.
Small ; : e2406110, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39113670

RESUMO

In this study, state-of-the-art on-line pyrolysis MS (OP-MS) equipped with temperature-controlled cold trap and on-line pyrolysis GC/MS (OP-GC/MS) injected through high-vacuum negative-pressure gas sampling (HVNPGS) programming are originally designed/constructed to identify/quantify the dynamic change of common permanent gases and micromolecule organics from the anode/cathode-electrolyte reactions during thermal runaway (TR) process, and corresponding TR mechanisms are further perfected/complemented. On LiCx anode side, solid electrolyte interphase (SEI) would undergo continuous decomposition and regeneration, and the R-H+ (e.g., HF, ROH, etc.) species derived from electrolyte decomposition would continue to react with Li/LiCx to generate H2. Up to above 200 °C, the O2 would release from the charged NCM cathode and organic radicals would be consumed/oxidized by evolved O2 to form COx, H2O, and more corrosive HF. On the contrary, charged LFP cathode does not present obvious O2 evolution during heating process and the unreacted flammable/toxic organic species would exit in the form of high temperature/high-pressure (HT/HP) vapors within batteries, indicating higher potential safety risks. Additionally, the in depth understanding of the TR mechanism outlined above provides a clear direction for the design/modification of thermostable electrodes and non-flammable electrolytes for safer batteries.

10.
J Transl Med ; 22(1): 46, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212795

RESUMO

BACKGROUND: Ovarian cancer (OC) is a malignant neoplasm that displays increased vascularization. Angiopoietin-like 4 (ANGPTL4) is a secreted glycoprotein that functions as a regulator of cell metabolism and angiogenesis and plays a critical role in tumorigenesis. However, the precise role of ANGPTL4 in the OC microenvironment, particularly its involvement in angiogenesis, has not been fully elucidated. METHODS: The expression of ANGPTL4 was confirmed by bioinformatics and IHC in OC. The potential molecular mechanism of ANGPTL4 was measured by RNA-sequence. We used a series of molecular biological experiments to measure the ANGPTL4-JAK2-STAT3 and ANGPTL4-ESM1 axis in OC progression, including MTT, EdU, wound healing, transwell, xenograft model, oil red O staining, chick chorioallantoic membrane assay and zebrafish model. Moreover, the molecular mechanisms were confirmed by Western blot, Co-IP and molecular docking. RESULTS: Our study demonstrates a significant upregulation of ANGPTL4 in OC specimens and its strong association with unfavorable prognosis. RNA-seq analysis affirms that ANGPTL4 facilitates OC development by driving JAK2-STAT3 signaling pathway activation. The interaction between ANGPTL4 and ESM1 promotes ANGPTL4 binding to lipoprotein lipase (LPL), thereby resulting in reprogrammed lipid metabolism and the promotion of OC cell proliferation, migration, and invasion. In the OC microenvironment, ESM1 may interfere with the binding of ANGPTL4 to integrin and vascular-endothelial cadherin (VE-Cad), which leads to stabilization of vascular integrity and ultimately promotes angiogenesis. CONCLUSION: Our findings underscore that ANGPTL4 promotes OC development via JAK signaling and induces angiogenesis in the tumor microenvironment through its interaction with ESM1.


Assuntos
Cistadenocarcinoma Seroso , Janus Quinase 2 , Neoplasias Ovarianas , Fator de Transcrição STAT3 , Animais , Feminino , Humanos , Microambiente Tumoral , Simulação de Acoplamento Molecular , Angiogênese , Peixe-Zebra/metabolismo , Carcinogênese , Proliferação de Células , Carcinoma Epitelial do Ovário , Neoplasias Ovarianas/genética , Linhagem Celular Tumoral , Proteína 4 Semelhante a Angiopoietina/genética , Proteínas de Neoplasias , Proteoglicanas
11.
Dig Dis Sci ; 69(3): 949-960, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218733

RESUMO

BACKGROUND AND AIMS: Hybrid endoscopic submucosal dissection (H-ESD), a modified ESD with a snare, has become increasingly utilized to overcome the limitations of conventional ESD (C-ESD). This study aimed to compare the efficacy and safety of Planned H-ESD and C-ESD for colorectal lesions. METHODS: Propensity score matching was performed to control for confounding variables in this retrospective study. Outcomes included en bloc resection and complete resection (R0) rates, procedure time, adverse event rates, and local recurrence rate. RESULTS: 1286 lesions were enrolled in the study. After matching, 263 lesions were assigned to each group. The Planned H-ESD group has lower en bloc rate but similar R0 resection rate compared to the C-ESD group (90.9% vs 98.1%, P = 0.001; 77.2% vs 77.9%, P = 0.917). The median procedure time was shorter in the Planned H-ESD group (27.0 min vs 35.0 min, P = 0.001). There were no significant differences in adverse events rates or local recurrence rate. Subgroup analysis based on lesion size revealed that a significantly lower en bloc resection rate in the Planned H-ESD group compared to the C-ESD group for lesions ≥ 40 mm (71.0% vs 94.3%, P = 0.027), but there was no significant difference for lesions < 40 mm. CONCLUSION: The Planned H-ESD has a lower en bloc resection rate but a similar R0 resection rate, adverse event rates, local recurrence rate, and shorter procedure duration. Compared to C-ESD, Planned H-ESD presents advantages for managing colorectal neoplasms below 40 mm.


Assuntos
Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Resultado do Tratamento , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Pontuação de Propensão , Estudos Retrospectivos , Neoplasias Colorretais/patologia
12.
Arch Insect Biochem Physiol ; 116(1): e22117, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38706214

RESUMO

More and more evidence shows that small noncoding RNAs (ncRNAs) play diverse roles in development, stress response and other cellular processes, but functional study of intermediate-size ncRNAs is still rare. Here, the expression profile of 16 intermediate-size ncRNAs in ovary and testis of silkworm Bombyx mori were analyzed. Twelve ncRNAs, including 5 small nucleolar RNAs (snoRNAs) and 7 unclassified ncRNAs, accumulated more in the testis than in the ovary of silkworm, especially Bm-163, Bm-51 and Bm-68. Four ncRNAs (including three orphan snoRNAs and one unclassified ncRNA) had higher expression level in the ovary than in the testis, especially Bm-86. Overexpression of the testis-enriched snoRNA Bm-68 in the female led to the accumulation of male-specific isoform of doublesex (BmdsxM) and increased the expression ratio of BmdsxM: BmdsxF. While overexpression of ovary-enriched snoRNA Bm-86 in the male decreased the expression ratio of BmdsxM: BmdsxF, indicating the roles of the two snoRNAs played in the alternative splicing of Bmdsx of silkworm, which will provide new clues for the functional study of snoRNAs in insects.


Assuntos
Processamento Alternativo , Bombyx , Proteínas de Ligação a DNA , Proteínas de Insetos , RNA Nucleolar Pequeno , Animais , Feminino , Masculino , Bombyx/genética , Bombyx/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Ovário/metabolismo , RNA Nucleolar Pequeno/genética , RNA Nucleolar Pequeno/metabolismo , Testículo/metabolismo
13.
Nano Lett ; 23(14): 6681-6688, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37440609

RESUMO

The initial Na loss limits the theoretical specific capacity of cathodes in Na-ion full cell applications, especially for Na-deficient P2-type cathodes. In this study, we propose a presodiation strategy for cathodes to compensate for the initial Na loss in Na-ion full cells, resulting in a higher specific capacity and a higher energy density. By employing an electrochemical presodiation approach, we inject 0.32 excess active Na into P2-type Na0.67Li0.1Fe0.37Mn0.53O2 (NLFMO), aiming to compensate for the initial Na loss in hard carbon (HC) and the inherent Na deficiency of NLFMO. The structure of the NLFMO cathode converts from P2 to P'2 upon active Na injection, without affecting subsequent cycles. As a result, the HC||NLFMOpreNa full cell exhibits a specific capacity of 125 mAh/g, surpassing the value of 61 mAh/g of the HC||NLFMO full cell without presodiation due to the injected active Na. Moreover, the presodiation effect can be achieved through other engineering approaches (e.g., Na-metal contact), suggesting the scalability of this methodology.

14.
Nano Lett ; 23(8): 3565-3572, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37026665

RESUMO

The prominent problem with graphite anodes in practical applications is the detrimental Li plating, resulting in rapid capacity fade and safety hazards. Herein, secondary gas evolution behavior during the Li-plating process was monitored by online electrochemical mass spectrometry (OEMS), and the onset of local microscale Li plating on the graphite anode was precisely/explicitly detected in situ/operando for early safety warnings. The distribution of irreversible capacity loss (e.g., primary and secondary solid electrolyte interface (SEI), dead Li, etc.) under Li-plating conditions was accurately quantified by titration mass spectroscopy (TMS). Based on OEMS/TMS results, the effect of typical VC/FEC additives was recognized at the level of Li plating. The nature of vinylene carbonate (VC)/fluoroethylene carbonate (FEC) additive modification is to enhance the elasticity of primary and secondary SEI by adjusting organic carbonates and/or LiF components, leading to less "dead Li" capacity loss. Though VC-containing electrolyte greatly suppresses the H2/C2H4 (flammable/explosive) evolution during Li plating, more H2 is released from the reductive decomposition of FEC.

15.
Nano Lett ; 23(17): 8194-8202, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37624651

RESUMO

Optimizing the interatomic distance of dual sites to realize C-C bond breaking of ethanol is critical for the commercialization of direct ethanol fuel cells. Herein, the concept of holding long-range dual sites is proposed to weaken the reaction barrier of C-C cleavage during the ethanol oxidation reaction (EOR). The obtained long-range Rh-O-Pt dual sites achieve a high current density of 7.43 mA/cm2 toward EOR, which is 13.3 times that of Pt/C, as well as remarkable stability. Electrochemical in situ Fourier transform infrared spectroscopy indicates that long-range Rh-O-Pt dual sites can increase the selectivity of C1 products and suppress the generation of a CO intermediate. Theoretical calculations further disclose that redistribution of the surface-localized electron around Rh-O-Pt can promote direct oxidation of -OH, accelerating C-C bond cleavage. This work provides a promising strategy for designing oxygen-bridged long-range dual sites to tune the activity and selectivity of complicated catalytic reactions.

16.
Molecules ; 29(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39124896

RESUMO

Three pairs of enantiomers and one achiral molecule that are new ethylated derivatives of sulfur and nitrogen-containing compounds named mantidisamides E-H (1-4), along with twenty known ones (5-24), were derived from the ethanol extract of Tenodera sinensis Saussure. The structures of these new compounds and their absolute configurations were assigned on the basis of spectroscopic analyses and computational methods. The assessment of activities in NRK-52e cells induced by TGF-ß1 demonstrated that the previously undescribed compounds 1 and 2 exhibited a significant capacity to inhibit the expression of proteins (fibronectin, collagen I, and α-SMA). Moreover, the biological activity of these compounds was found to increase with rising concentrations. Notably, compounds 1-4 should be artifacts; however, undescribed compounds 1 and 2, which possessed obvious biological activity, might be attractive for chemists and biologists due to the potential for more detailed exploration of their properties. It is worth mentioning that compounds 1 and 2 remain novel structures even in the absence of the ethoxy group.


Assuntos
Nitrogênio , Animais , Ratos , Nitrogênio/química , Enxofre/química , Linhagem Celular , Estrutura Molecular , Fibrose
17.
Angew Chem Int Ed Engl ; 63(14): e202317922, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38366167

RESUMO

Carbon coating layers have been found to improve the catalytic performance of transition metals, which is usually explained as an outcome of electronic synergistic effect. Herein we reveal that the defective graphitic carbon, with a unique interlayer gap of 0.342 nm, can be a highly selective natural molecular sieve. It allows efficient diffusion of hydrogen molecules or radicals both along the in-plane and out-of-plane direction, but sterically hinders the diffusion of molecules with larger kinetic diameter (e.g., CO and O2) along the in-plane direction. As a result, poisonous species lager than 0.342 nm are sieved out, even when their adsorption on the metal is thermodynamically strong; at the same time, the interaction between H2 and the metal is not affected. This natural molecular sieve provides a very chance for constructing robust metal catalysts for hydrogen-relevant processes, which are more tolerant to chemical or electrochemical oxidation or CO-relevant poisoning.

18.
Angew Chem Int Ed Engl ; : e202412214, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141606

RESUMO

Electrolyte engineering is crucial for improving cathode electrolyte interphase (CEI) to enhance the performance of lithium-ion batteries, especially at high charging cut-off voltages. However, typical electrolyte modification strategies always focus on the solvation structure in the bulk region, but consistently neglect the dynamic evolution of electrolyte solvation configuration at the cathode-electrolyte interface, which directly influences the CEI construction. Herein, we reveal an anti-synergy effect between Li+-solvation and interfacial electric field by visualizing the dynamic evolution of electrolyte solvation configuration at the cathode-electrolyte interface, which determines the concentration of interfacial solvated-Li+. The Li+ solvation in the charging process facilitates the construction of a concentrated (Li+-solvent/anion-rich) interface and anion-derived CEI, while the repulsive force derived from interfacial electric field induces the formation of a diluted (solvent-rich) interface and solvent-derived CEI. Modifying the electrochemical protocols and electrolyte formulation, we regulate the "inflection voltage" arising from the anti-synergy effect and prolong the lifetime of the concentrated interface, which further improves the functionality of CEI architecture.

19.
Angew Chem Int Ed Engl ; 63(17): e202400254, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38441399

RESUMO

Acting as a passive protective layer, solid-electrolyte interphase (SEI) plays a crucial role in maintaining the stability of the Li-metal anode. Derived from the reductive decomposition of electrolytes (e.g., anion and solvent), the SEI construction presents as an interfacial process accompanied by the dynamic de-solvation process during Li-metal plating. However, typical electrolyte engineering and related SEI modification strategies always ignore the dynamic evolution of electrolyte configuration at the Li/electrolyte interface, which essentially determines the SEI architecture. Herein, by employing advanced electrochemical in situ FT-IR and MRI technologies, we directly visualize the dynamic variations of solvation environments involving Li+-solvent/anion. Remarkably, a weakened Li+-solvent interaction and anion-lean interfacial electrolyte configuration have been synchronously revealed, which is difficult for the fabrication of anion-derived SEI layer. Moreover, as a simple electrochemical regulation strategy, pulse protocol was introduced to effectively restore the interfacial anion concentration, resulting in an enhanced LiF-rich SEI layer and improved Li-metal plating/stripping reversibility.

20.
Angew Chem Int Ed Engl ; 63(6): e202316790, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38116869

RESUMO

Electrolyte engineering is a fascinating choice to improve the performance of Li-rich layered oxide cathodes (LRLO) for high-energy lithium-ion batteries. However, many existing electrolyte designs and adjustment principles tend to overlook the unique challenges posed by LRLO, particularly the nucleophilic attack. Here, we introduce an electrolyte modification by locally replacing carbonate solvents in traditional electrolytes with a fluoro-ether. By benefit of the decomposition of fluoro-ether under nucleophilic O-related attacks, which delivers an excellent passivation layer with LiF and polymers, possessing rigidity and flexibility on the LRLO surface. More importantly, the fluoro-ether acts as "sutures", ensuring the integrity and stability of both interfacial and bulk structures, which contributed to suppressing severe polarization and enhancing the cycling capacity retention from 39 % to 78 % after 300 cycles for the 4.8 V-class LRLO. This key electrolyte strategy with comprehensive analysis, provides new insights into addressing nucleophilic challenge for high-energy anionic redox related cathode systems.

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