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Oocyte meiotic maturation failure and chromosome abnormality is one of the main causes of infertility, abortion, and diseases. The mono-orientation of sister chromatids during the first meiosis is important for ensuring accurate chromosome segregation in oocytes. MEIKIN is a germ cell-specific protein that can regulate the mono-orientation of sister chromatids and the protection of the centromeric cohesin complex during meiosis I. Here we found that MEIKIN is a maternal protein that was highly expressed in mouse oocytes before the metaphase I (MI) stage, but became degraded by the MII stage and dramatically reduced after fertilization. Strikingly, MEIKIN underwent phosphorylation modification after germinal vesicle breakdown (GVBD), indicating its possible function in subsequent cellular event regulation. We further showed that MEIKIN phosphorylation was mediated by PLK1 at its carboxyl terminal region and its C-terminus was its key functional domain. To clarify the biological significance of meikin degradation during later stages of oocyte maturation, exogenous expression of MEIKIN was employed, which showed that suppression of MEIKIN degradation resulted in chromosome misalignment, cyclin B1 and Securin degradation failure, and MI arrest through a spindle assembly checkpoint (SAC)-independent mechanism. Exogenous expression of MEIKIN also inhibited metaphase II (MII) exit and early embryo development. These results indicate that proper MEIKIN expression level and its C-terminal phosphorylation by PLK1 are critical for regulating the metaphase-anaphase transition in meiotic oocyte. The findings of this study are important for understanding the regulation of chromosome segregation and the prevention meiotic abnormality.
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Background: The characteristics of scoliosis afflicting school children and adolescents in mainland China are still unclear. Therefore, we conducted a systematic review to estimate scoliosis's prevalence and characterise its distribution in China. Methods: We screened PubMed, Scopus, WanFang, China National Knowledge Infrastructure, National Science and Technology Library, and WeiPu databases for mainland China articles published between 1 January 1980 and 31 October 2022. Among them, we identified population-wide scoliosis studies in school children and adolescents. The main outcomes were the positive rate of primary screening and the prevalence of final screening. Primary screening mainly included general examination with/without the forward bending test in school. The final screening entailed clinical diagnosis by Röntgen radiation in a hospital (based on primary screening). A meta-analysis of scoliosis distribution by gender was performed to calculate the odds ratios (ORs) and 95% confidence intervals (CIs). Further, we analysed the distributions of scoliosis by age, region, aetiological type, and severity of curvature, in addition to the correlation between its prevalence and altitude or latitude. Results: 77 studies with 2 224 320 participants were included. The positive rate through primary screening was 3.97%, whereas the prevalence of scoliosis at final screening was 1.20%. Analysing the data revealed a higher prevalence of scoliosis in girls (OR = 1.57; 95% CI = 1.38-1.81). The age-wise peak rate of scoliosis was 15-16 years (1.07%) in boys and 13-14 years (1.42%) in girls. The mean prevalence of scoliosis was 1.07% in the western region, 1.54% in the central, and 1.35% in the eastern. Scoliosis prevalence was not correlated with either altitude or latitude. The prevalence of idiopathic and congenital scoliosis was 1.18 and 0.03%. Among all subjects with scoliosis, 79.10 and 16.80% had mild and medium disease severity. Conclusions: According to this comprehensive study using data sets of scoliosis in adolescents across mainland China, the mean prevalence of scoliosis is 1.20%, yet 1.57 times higher in girls than boys, and is most prevalent in the middle region. Overall, scoliosis in adolescents could pose a burden to public health in mainland China. Registration: PROSPERO CRD42021231987.
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Escoliose , Adolescente , Feminino , Humanos , Masculino , China/epidemiologia , Prevalência , Escoliose/epidemiologiaRESUMO
Energy storage devices operating at low temperatures are plagued by sluggish kinetics, reduced capacity, and notorious dendritic growth. Herein, novel potassium dual-ion batteries (PDIBs) capable of superior performance at -60 °C, and fabricated by combining MXenes and polytriphenylamine (PTPAn) as the anode and cathode, respectively, are presented. Additionally, the reason for the anomalous kinetics of K+ (faster at low temperature than at room temperature) on the Ti3C2 anode is investigated. Theoretical calculations, crossover experiments, and in situ XRD at room and low temperatures revealed that K+ tends to bind with solvent molecules rather than anions at subzero temperatures, which not only inhibits the participation of PF6 - in the formation of the solid electrolyte interphase (SEI), but also guarantees co-intercalation behavior and suppresses undesirable K+ storage. The advantageous properties at low temperatures endow the Ti3C2 anode with fast K+ kinetics to unlock the outstanding performance of PDIB at ultralow temperatures. The PDIBs exhibit superior rate capability and high capacity retention at -40 °C and -60 °C. Impressively, after charging-discharging for 20,000â cycles at -60 °C, the PDIB retained 86.7 % of its initial capacity. This study reveals the influence of temperatures on MXenes and offers a unique design for dual-ion batteries operating at ultralow temperatures.
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Fangchinoline (FA) is an alkaloid derived from the traditional Chinese medicine Fangji. Numerous studies have shown that FA has a toxic effect on various cancer cells, but little is known about its toxic effects on germ cells, especially oocytes. In this study, we investigated the effects of FA on mouse oocyte maturation and its potential mechanisms. Our results showed that FA did not affect meiosis resumption but inhibited the first polar body extrusion. This inhibition is not due to abnormalities at the organelle level, such as chromosomes and mitochondrial, which was proved by detection of DNA damage and reactive oxygen species. Further studies revealed that FA arrested the oocyte at the metaphase I stage, and this arrest was not caused by abnormal kinetochore-microtubule attachment or spindle assembly checkpoint activation. Instead, FA inhibits the activity of anaphase-promoting complexes (APC/C), as evidenced by the inhibition of CCNB1 degeneration. The decreased activity of APC/C may be due to a reduction in CDC25B activity as indicated by the high phosphorylation level of CDC25B (Ser323). This may further enhance Maturation-Promoting Factor (MPF) activity, which plays a critical role in meiosis. In conclusion, our study suggests that the metaphase I arrest caused by FA may be due to abnormalities in MPF and APC/C activity.
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Benzilisoquinolinas , Fator Promotor de Maturação , Meiose , Mesotelina , Oócitos , Animais , Meiose/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Feminino , Benzilisoquinolinas/farmacologia , Fator Promotor de Maturação/metabolismo , Camundongos , Fosfatases cdc25/metabolismo , Fosfatases cdc25/genética , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Camundongos Endogâmicos ICR , Espécies Reativas de Oxigênio/metabolismo , Dano ao DNA/efeitos dos fármacos , Ciclina B1/metabolismo , Ciclina B1/genéticaRESUMO
LiFePO4 is widely used because of its high safety and cycle stability, but its inefficient electronic conductivity combined with sluggish Li+ diffusivity restricts its performance. To overcome this obstacle, applying a layer of conductive carbon onto the surface of LiFePO4 has the greatest improvement in electronic conductivity and Li+ diffusivity. However, the rate performance of carbon-coated LiFePO4 makes it difficult to meet the application requirements. Although nitrogen doping improves electrochemical performance by providing active sites and electronic conductivity, the N-doped carbon coating is prone to agglomeration, which causes a sharp decrease in capacity when the current rate increases. In this work, a synergistic N, Mn codoping strategy is implemented to overcome the aforementioned drawbacks by disrupting the large agglomeration of C-N bonds, improving the uniformity of the surface coating layer to enhance the completeness of the conductive network and increasing the number of Li+ diffusion channels, and thus accelerating the mass transfer rate under high-rate current. Consequently, this strategy effectively improves the rate capability (119 mA h g-1 at 10 C) while maintaining excellent cycling performance (88% capacity retention over 600 cycles at 5 C). This work improves the rate of ion diffusion and the rate capability of micrometer-sized LiFePO4, thus, enabling its wider application.
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Wearable sweat sensor offers a promising means for noninvasive real-time health monitoring, but the efficient collection and accurate analysis of sweat remains challenging. One of the obstacles is to precisely modulate the surface wettability of the microfluidics to achieve efficient sweat collection. Here a facile initiated chemical vapor deposition (iCVD) method is presented to grow and pattern polymer nanocone arrays with distinct superwettability on polydimethylsiloxane microfluidics, which facilitate highly efficient sweat transportation and collection. The nanoarray is synthesized by manipulating monomer supersaturation during iCVD to induce controlled nucleation and preferential vertical growth of fluorinated polymer. Subsequent selective vapor deposition of a conformal hydrogel nanolayer results in superhydrophilic nanoarray floor and walls within the microchannel that provide a large capillary force and a superhydrophobic ceiling that drastically reduces flow friction, enabling rapid sweat transport along varied flow directions. A carbon/hydrogel/enzyme nanocomposite electrode is then fabricated by sequential deposition of highly porous carbon nanoparticles and hydrogel nanocoating to achieve sensitive and stable sweat detection. Further encapsulation of the assembled sweatsensing patch with superhydrophobic nanoarray imparts self-cleaning and water-proof capability. Finally, the sweat sensing patch demonstrates selective and sensitive glucose and lactate detection during the on-body test.
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The Covering Location Problem (CLP) is widely used for the efficient facility distribution. However, existing algorithms for this problem suffer from long computation times or suboptimal solutions. To address this, we propose two methods based on graph convolutional networks (GCN) to solve two types of covering location problems: the location set covering problem and the maximum covering location problem. The first method, GCN-Greedy, is a supervised algorithm that synergized with the Greedy algorithm as decoder. It designs a specialized loss function to train the model, tailored to the characteristics of the two covering location problems. The second method, reinforcement learning based on GCN with auto-regressive decoder (GCN-AR-RL), represents a reinforcement learning framework that integrates a GCN encoder with an auto-regressive decoder. The experimental results of these models demonstrate the remarkable accuracy and performance advantages. Additionally, we apply these two models to the realistic dataset and achieve good performance.
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In layered Li-rich materials, over stoichiometric Li forms an ordered occupation of LiTM6 in transition metal (TM) layer, showing a honeycomb superstructure along [001] direction. At the atomic scale, the instability of the superstructure at high voltage is the root cause of problems such as capacity/voltage decay of Li-rich materials. Here a Li-rich material with a high Li/Ni disorder is reported, these interlayer Ni atoms locate above the honeycomb superstructure and share adjacent O coordination with honeycomb TM. These NiâO bonds act as cable-stayed bridge to the honeycomb plane, and improve the high-voltage stability. The cable-stayed honeycomb superstructure is confirmed by in situ X-ray diffraction to have a unique cell evolution mechanism that it can alleviate interlaminar lattice strain by promoting in-plane expansion along a-axis and inhibiting c-axis stretching. Electrochemical tests also demonstrate significantly improved long cycle performance after 500 cycles (86% for Li-rich/Li half cell and 82% for Li-rich/Si-C full cell) and reduced irreversible oxygen release. This work proves the feasibility of achieving outstanding stability of lithium-rich materials through superstructure regulation and provides new insights for the development of the next-generation high-energy-density cathodes.
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A novel electrochemical biosensor was developed for the detection of epinephrine (EP) by immobilizing double-strand DNA (dsDNA) bound with copper ions on a gold electrode (Cu2+/dsDNA/MCH/AuE). The electrochemical behavior of EP at Cu2+/dsDNA/MCH/AuE was examined, and the results demonstrated a significant enhancement in the electrocatalytic oxidation peak current of EP due to the formation of a stable G-Cu(II)-G sandwich structure between Cu2+ and guanine at the modified electrode. The modification process of the electrode was characterized by scanning electron microscopy, infrared spectroscopy, electrochemical impedance spectroscopy, and differential pulse voltammetry. A study on the effect of pH in phosphate buffer solution on the electrochemical oxidation of EP indicated that the catalytic oxidation process was pH-dependent. A plot of catalytic current versus EP concentration exhibited a dual-linear relationship within two ranges: 1.0-12.5 µM and 12.5-1000.0 µM, with correlation coefficients of 0.995 and 0.997, respectively. The limit of detection was determined to be 47 nM (S/N = 3). According to the calculated Hill coefficient (0.99), it can be concluded that the electrocatalytic process followed the Michaelis-Menten kinetic mechanism. The maximum catalytic current Im was 25 µA, while the apparent Michaelis-Menten constant Km was 1.425 mM. These findings indicated excellent electrocatalytic activity of the modified electrode towards oxidation of EP. The developed biosensor successfully detected EP in spiked mouse serum as well as epinephrine hydrochloride injection with high selectivity, sensitivity, stability, and accuracy.
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Técnicas Biossensoriais , Cobre , DNA , Técnicas Eletroquímicas , Eletrodos , Epinefrina , Ouro , Epinefrina/análise , Epinefrina/sangue , Cobre/química , Técnicas Biossensoriais/métodos , DNA/química , Técnicas Eletroquímicas/métodos , Ouro/química , Limite de Detecção , Animais , Oxirredução , Concentração de Íons de HidrogênioRESUMO
The Qinghai-Tibet Plateau (QTP) serves as a vital barrier for both national security and ecological preservation. Overpopulation and urban sprawl pose threats to its ecological security, while underpopulation and small urban cities also undermine national security. Hence, optimizing population distribution and urban development on the QTP is crucial for bolstering the national security perimeter and ensuring basic modernisation across China. Nonetheless, understanding the population carrying capacity (CC) of the QTP and how large cities can safeguard both national security and ecological stability remains limited. To address this research gap, we utilised various model algorithms and methodologies to assess the population CC and urban scale of the QTP from seven different perspectives. The results indicate that the permanent population CC of the QTP in 2050 will be 26.2 million people, with an urbanisation level of 57.25 %, thereby allowing 15 million people to enter cities. Thus, the QTP can add 13.07 million people to its permanent population in the future, with a newly added urban population of 8.75 million, increasing the urbanisation level by 9.67 %. The future permanent population will mainly be distributed in the Xining, Lhasa, and Qaidam metropolitan areas. Combined, the permanent and urban populations will account for 38.54 % and 49.84 % of the QTP, respectively. Moreover, these populations will be moderately dispersed in 11 important node cities and more widely dispersed in key border towns. These findings provide a scientific basis for the sustainable development and high-quality urbanisation of the QTP, which have important implications for achieving sustainable development goals, offering crucial references for governments to formulate resource management policies and achieve sustainable resource utilisation.
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Cidades , Urbanização , Urbanização/tendências , Tibet , China , Humanos , Conservação dos Recursos NaturaisRESUMO
Environmental factors such as diet and lifestyle can influence the health of both mothers and offspring. However, its transgenerational transmission and underlying mechanisms remain largely unknown. Here, using a maternal lactation-period low-protein diet (LPD) mouse model, we show that maternal LPD during lactation causes decreased survival and stunted growth, significantly reduces ovulation and litter size, and alters the gut microbiome in the female LPD-F1 offspring. The transcriptome of LPD-F1 metaphase II (MII) oocytes shows that differentially expressed genes are enriched in female pregnancy and multiple metabolic processes. Moreover, maternal LPD causes early stunted growth and impairs metabolic health, which is transmitted over two generations. The methylome alteration of LPD-F1 oocytes can be partly transmitted to the F2 oocytes. Together, our results reveal that LPD during lactation transgenerationally affects offspring health, probably via oocyte epigenetic changes.
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Dieta com Restrição de Proteínas , Lactação , Animais , Feminino , Lactação/genética , Dieta com Restrição de Proteínas/efeitos adversos , Camundongos , Gravidez , Oócitos/metabolismo , Microbioma Gastrointestinal , Epigênese Genética , Fenômenos Fisiológicos da Nutrição Materna , Transcriptoma/genética , Masculino , Metilação de DNA , Efeitos Tardios da Exposição Pré-Natal/genéticaRESUMO
The timely degradation of proteins that regulate the cell cycle is essential for oocyte maturation. Oocytes are equipped to degrade proteins via the ubiquitin-proteasome system. In meiosis, anaphase promoting complex/cyclosome (APC/C), an E3 ubiquitin-ligase, is responsible for the degradation of proteins. Ubiquitin-conjugating enzyme E2 S (UBE2S), an E2 ubiquitin-conjugating enzyme, delivers ubiquitin to APC/C. APC/C has been extensively studied, but the functions of UBE2S in oocyte maturation and mouse fertility are not clear. In this study, we used Ube2s knockout mice to explore the role of UBE2S in mouse oocytes. Ube2s-deleted oocytes were characterized by meiosis I arrest with normal spindle assembly and spindle assembly checkpoint dynamics. However, the absence of UBE2S affected the activity of APC/C. Cyclin B1 and securin are two substrates of APC/C, and their levels were consistently high, resulting in the failure of homologous chromosome separation. Unexpectedly, the oocytes arrested in meiosis I could be fertilized and the embryos could become implanted normally, but died before embryonic day 10.5. In conclusion, our findings reveal an indispensable regulatory role of UBE2S in mouse oocyte meiosis and female fertility.
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Pontos de Checagem da Fase M do Ciclo Celular , Meiose , Animais , Feminino , Camundongos , Ciclossomo-Complexo Promotor de Anáfase/genética , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Oócitos/metabolismo , Ubiquitinas/metabolismoRESUMO
The main group metals are commonly perceived as catalytically inert in the context of oxygen reduction reactions (ORR) due to the delocalized valence orbitals. Regulating the local environment and structure of metal center coordinated by nitrogen ligands (M-Nx) is a promising approach to accelerate catalytic dynamics. Herein, we, for the first time, report the atomically dispersed Al catalysts coordinated with N and C atoms for 4-electron ORR. The axial coordinated pyrrolyl N group (No) is constructed in the Al-N4-No moiety to regulate the p-band structure of Al center, effectively steering the local environment and structure of the square planar Al-N4 sites, which typically exhibit too strong interaction with ORR intermediates. The dynamic covalency competition of axial Al-No and Al-O bonding could endow the Al center with moderate hybridization between Al 3p orbital and O 2p orbital, alleviating the binding energy of ORR intermediates. The as-prepared Al-N4-No electrocatalyst exhibits excellent ORR activity, selectivity, and durability, along with the rapid kinetics as demonstrated by in situ Raman spectroscopy. This work offers a fundamental comprehension of the fine regulation on p-band and guides the rational design of main-group metal-based single atom catalysts.
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Background: Low back pain (LBP) is reported as an urgent public-health concern globally because it occurs in all age groups and is now the leading cause of disability, with health systems unable to cope with this burden. We present China's burden of LBP by estimating its prevalence and years lived with disability (YLDs) from 1990 to 2019. Methods: We obtained the data relating to LBP from the Global Burden of Disease Database (GBD) 2019. Then we calculated years lived with disability caused by LBP by multiplying the prevalence of LBP sequelae by their corresponding disability weights. We performed an analysis of the age-, sex-, and province-specific prevalence and YLDs of 33 provinces/regions in China, as well as their relationship with the sociodemographic index (SDI). Results: China has the largest numbers of people with LBP (91.3 million) and YLDs (8.6 million) globally, and LBP is the leading cause of YLDs. The age-standardised prevalence was 7.25% in 1990, and this decreased to 5.13% in 2019. The age-standardised YLD rate was 579/100 000 in 2019, having decreased by 28.97%. Both measurements increased with age, being higher in women and varying across the 33 provinces/regions. For the 5-to-14-year age group, the prevalence (4.50%) and YLD rate (4.51%) increased in 2019 from 1990 (3.21% and 3.21%, respectively) when compared to the elderly group. Age-standardised YLD rates experienced decreases with increasing SDI, while there was an increasing tendency as SDI increased further; the changes for women were more obvious. Conclusions: Over the three decades considered, China has continued to have the largest number of people with LBP in the world, even though the age-standardised prevalence has decreased. YLDs were found to decrease as SDI increased, but they subsequently increased again. LBP still presents a burden, particularly for children and postmenopausal women.
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COVID-19 , Dor Lombar , Criança , Humanos , Feminino , Idoso , Carga Global da Doença , Dor Lombar/epidemiologia , Saúde Global , COVID-19/epidemiologia , Prevalência , China/epidemiologiaRESUMO
When the electric field strength (E) surpasses a certain threshold, secondary droplets are generated during the coalescence between water droplets in oil and the oil-water interface (so-called the droplet-interface partial coalescence phenomenon), resulting in a lower efficiency of droplet electrocoalescence. This study employs molecular dynamics (MD) simulations to investigate the droplet-interface partial coalescence phenomenon under direct current (DC) electric fields. The results demonstrate that intermolecular interactions, particularly the formation of hydrogen bonds, play a crucial role in dipole-dipole coalescence. Droplet-interface partial coalescence is categorized into five regimes based on droplet morphology. During the contact and fusion of the droplet with the water layer, the dipole moment of the droplet exhibits alternating increases and decreases along the electric field direction. Electric field forces acting on sodium ions and the internal interactions within droplets promote the process of droplet-interface partial coalescence. High field strengths cause significant elongation of the droplet, leading to its fragmentation into multiple segments. The migration of hydrated ions has a dual impact on the droplet-interface partial coalescence, with both facilitative and suppressive effects. The time required for droplet-interface partial coalescence initially decreases and subsequently increases as the field strength increases, depending on the competitive relationship between the extent of droplet stretching and the electric field force. This work provides molecular insights into the droplet-interface coalescence mechanisms in water-in-oil emulsions under DC electric fields.
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As next-generation energy storage devices, lithium metal batteries (LMBs) must offer high safety, high-voltage resistance, and a long life span. Electrolyte engineering is a facile strategy to tailor the interfacial chemistry of LMBs. In particular, the solvation structure and derived solid electrolyte interphase (SEI) are crucial for a satisfactory battery performance. Herein, a novel middle-concentrated ionic liquid electrolyte (MCILE) with an anion-rich solvation structure tuned by difluorinated cations is demonstrated to achieve ultrahigh safety, high-voltage stability, and excellent ternary-cathode compatibility. Novel gem-difluorinated cations first synthesized for prestoring fluorine on positively charged species, not only preferentially adsorb in the inner-Helmholtz layers, but also participate in regulating the Li+ solvation structure, resulting in a robust interphase. Moreover, these weak interactions in the Li+ solvation structure including anion-solvent and ionic liquid (IL) cation-solvent pairs are first revealed, which are beneficial for promoting an anion-dominated solvation structure and the desolvation process. Benefiting from the unique anion-rich solvation structure, a stable hetero-SEI structure is obtained. The designed MCILE exhibits compatibility with Li metal anode and the high-voltage ternary cathode at high temperatures (60 °C). This work provides a new approach for regulating the solvation structure and electrode interphase chemistry of LMBs via difluorinated IL cations.
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Atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts have exhibited encouraging oxygen reduction reaction (ORR) activity. Nevertheless, the insufficient long-term stability remains a widespread concern owing to the inevitable 2-electron byproducts, H2O2. Here, we construct Co-N-Cr cross-interfacial electron bridges (CIEBs) via the interfacial electronic coupling between Cr2O3 and Co-N-C, breaking the activity-stability trade-off. The partially occupied Cr 3d-orbitals of Co-N-Cr CIEBs induce the electron rearrangement of CoN4 sites, lowering the Co-OOH* antibonding orbital occupancy and accelerating the adsorption of intermediates. Consequently, the Co-N-Cr CIEBs suppress the two-electron ORR process and approach the apex of Sabatier volcano plot for four-electron pathway simultaneously. As a proof-of-concept, the Co-N-Cr CIEBs is synthesized by the molten salt template method, exhibiting dominant 4-electron selectively and extremely low H2O2 yield confirmed by Damjanovic kinetic analysis. The Co-N-Cr CIEBs demonstrates impressive bifunctional oxygen catalytic activity (âµE=0.70â V) and breakthrough durability including 100 % current retention after 10â h continuous operation and cycling performance over 1500â h for Zn-air battery. The hybrid interfacial configuration and the understanding of the electronic coupling mechanism reported here could shed new light on the design of superdurable M-N-C catalysts.
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Previously a ring finger protein 20 (RNF20) is found to be essential for meiotic recombination and mediates H2B ubiquitination during spermatogenesis. However, its role in meiotic division is still unknown. Here, it is shown that RNF20 is localized at both centromeres and spindle poles, and it is required for oocyte acentrosomal spindle organization and female fertility. RNF20-depleted oocytes exhibit severely abnormal spindle and chromosome misalignment caused by defective bipolar organization. Notably, it is found that the function of RNF20 in spindle assembly is not dependent on its E3 ligase activity. Instead, RNF20 regulates spindle assembly by recruiting tropomyosin3 (TPM3) to both centromeres and spindle poles with its coiled-coil motif. The RNF20-TPM3 interaction is essential for acentrosomal meiotic spindle assembly. Together, the studies uncover a novel function for RNF20 in mediating TPM3 recruitment to both centromeres and spindle poles during oocyte spindle assembly.
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Meiose , Fuso Acromático , Masculino , Feminino , Humanos , Fuso Acromático/metabolismo , Oócitos/metabolismo , Polos do Fuso/metabolismo , CentrômeroRESUMO
Stabilizing electrolytes for high-voltage lithium metal batteries (LMBs) is crucial yet challenging, as they need to ensure stability against both Li anodes and high-voltage cathodes (above 4.5â V versus Li/Li+ ), addressing issues like poor cycling and thermal runaway. Herein, a novel gem-difluorinated skeleton of ionic liquid (IL) is designed and synthesized, and its non-flammable electrolytes successfully overcome aforementioned challenges. By creatively using dual salts, fluorinated ionic liquid and dimethyl carbonate as a co-solvent, the solvation structure of Li+ ions is efficiently controlled through electrostatic and weak interactions that are well unveiled and illuminated via nuclear magnetic resonance spectra. The as-prepared electrolytes exhibit high security avoiding thermal runaway and show excellent compatibility with high-voltage cathodes. Besides, the solvation structure derives a robust and stable F-rich interphase, resulting in high reversibility and Li-dendrite prevention. LiNi0.6 Co0.2 Mn0.2 O2 /Li LMBs (4.5â V) demonstrate excellent long-term stability with a high average Coulombic efficiency (CE) of at least 99.99 % and a good capacity retention of 90.4 % over 300 cycles, even can work at a higher voltage of 4.7â V. Furthermore, the ultrahigh Ni-rich LiNi0.88 Co0.09 Mn0.03 O2 /Li system also delivers excellent electrochemical performance, highlighting the significance of fluorinated IL-based electrolyte design and enhanced interphasial chemistry in improving battery performance.