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Aqueous lithium-ion batteries (ALIBs) are promising for large-scale energy storage systems because of the cost-effective, intrinsically safe, and environmentally friendly properties of aqueous electrolytes. Practical application is however impeded by interfacial side-reactions and the narrow electrochemical stability window (ESW) of aqueous electrolytes. Even though higher electrolyte salt concentrations (e.g., water-in-salt electrolyte) enhance performance by widening the ESW, the nature and extent of side-reaction processes are debated and more fundamental understanding thereof is needed. Herein, the interfacial chemistry of one of the most popular electrode materials, V2O5, for aqueous batteries is systematically explored by a unique set of operando analytical techniques. By monitoring electrode/electrolyte interphase deposition, electrolyte pH, and gas evolution, the highly dynamic formation/dissolution of V2O5/V2O4, Li2CO3 and LiF during dis-/charge is demonstrated and shown to be coupled with electrolyte decomposition and conductive carbon oxidation, regardless of electrolyte salt concentration. The study provides deeper understanding of interfacial chemistry of active materials under variable proton activity in aqueous electrolytes, hence guiding the design of more effective electrode/electrolyte interfaces for ALIBs and beyond.
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Li[LixNiyMnzCo1-x-y-z]O2 (lithium-rich NMCs) are benchmark cathode materials receiving considerable attention due to the abnormally high capacities resulting from their anionic redox chemistry. Although their anionic redox mechanisms have been much investigated, the roles of cationic redox processes remain underexplored, hindering further performance improvement. Here we decoupled the effects of nickel and cobalt in lithium-rich NMCs via a comprehensive study of two typical compounds, Li1.2Ni0.2Mn0.6O2 and Li1.2Co0.4Mn0.4O2. We discovered that both Ni3+/4+ and Co4+, generated during cationic redox processes, are actually intermediate species for triggering oxygen redox through a ligand-to-metal charge-transfer process. However, cobalt is better than nickel in mediating the kinetics of ligand-to-metal charge transfer by favouring more transition metal migration, leading to less cationic redox but more oxygen redox, more O2 release, poorer cycling performance and more severe voltage decay. Our work highlights a compositional optimization pathway for lithium-rich NMCs by deviating from using cobalt to using nickel, providing valuable guidelines for future high-capacity cathode design.
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This study explores the transcriptomic differences in two distinct phases of Ecytonucleospora hepatopenaei (EHP) in Litopenaeus vannamei, a crucial aspect in shrimp health management. We employed high-throughput sequencing to categorize samples into two phases, 'Phase A' and 'Phase B', defined by the differential expression of PTP2 and TPS1 genes. Our analysis identified 2057 genes, with 78 exhibiting significant variances, including 62 upregulated and 16 downregulated genes. Enrichment analyses via GO and KEGG pathways highlighted these genes' roles in cellular metabolism, signal transduction, and immune responses. Notably, genes like IQGAP2, Rhob, Pim1, and PCM1 emerged as potentially crucial in EHP's infection process and lifecycle. We hypothesize that these genes may influence trehalose metabolism and glucose provision, impacting the biological activities within EHP during different phases. Interestingly, a lower transcript count in 'Phase A' EHP suggests a reduction in biological activities, likely preparing for host cell invasion. This research provides a foundational understanding of EHP infection mechanisms, offering vital insights for future studies and therapeutic interventions.
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Enterocytozoon , Penaeidae , Animales , Enterocytozoon/fisiología , Perfilación de la Expresión Génica , Transcriptoma , Penaeidae/genética , Alimentos MarinosRESUMEN
Reversible anionic redox reactions represent a transformational change for creating advanced high-energy-density positive-electrode materials for lithium-ion batteries. The activation mechanism of these reactions is frequently linked to ligand-to-metal charge transfer (LMCT) processes, which have not been fully validated experimentally due to the lack of suitable model materials. Here we show that the activation of anionic redox in cation-disordered rock-salt Li1.17Ti0.58Ni0.25O2 involves a long-lived intermediate Ni3+/4+ species, which can fully evolve to Ni2+ during relaxation. Combining electrochemical analysis and spectroscopic techniques, we quantitatively identified that the reduction of this Ni3+/4+ species goes through a dynamic LMCT process (Ni3+/4+-O2- â Ni2+-On-). Our findings provide experimental validation of previous theoretical hypotheses and help to rationalize several peculiarities associated with anionic redox, such as cationic-anionic redox inversion and voltage hysteresis. This work also provides additional guidance for designing high-capacity electrodes by screening appropriate cationic species for mediating LMCT.
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Litio , Cationes , Electrodos , Ligandos , Litio/química , Oxidación-ReducciónRESUMEN
Enterocytozoon hepatopenaei (EHP) is a prevalent microsporidian pathogen responsible for hepatopancreatic microsporidiosis (HPM) in Litopenaeus vannamei. This infection not only leads to slowed growth in shrimp abut aslo inflicts substantial economic losses in the global aquaculture industry. However, the molecular mechanisms by which EHP influences the host during various infection stages remain unclear. This study employed comparative transcriptomics to examine the effects of EHP infection on Litopenaeus vannamei between early and late stage of infection groups. Utilizing transcriptomic approaches, we identified differentially expressed genes (DEGs) with notable biological significance through the COG, GO, KEGG, GSEA, and Mufzz time-series methodologies. The results reveal that EHP infection considerably influences host gene expression, with marked differences between early and late infection across distinct timeframes. Key processes such as detoxification, cell apoptosis, and lipid metabolism are pivotal during host-parasite interactions. Hexokinase and phosphatidic acid phosphatase emerge as key factors enabling invasion and sustained effects. Cytochrome P450 and glucose-6-phosphate dehydrogenase could facilitate infection progression. EHP significantly impacts growth, especially through ecdysteroids and 17ß-estradiol dehydrogenase. By delineating stage-specific effects, we gain insights into interaction between EHP and Litopenaeus vannamei, showing how intracellular pathogens reprogram host defenses into mechanisms enabling long-term persistence. This study provides a deeper understanding of host-pathogen dynamics, emphasizing the interplay between detoxification, metabolism, immunity, apoptosis and growth regulation over the course of long-term symbiosis.
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Penaeidae , Transcriptoma , Animales , Simbiosis , Perfilación de la Expresión Génica/veterinaria , Acuicultura , Penaeidae/genéticaRESUMEN
The tremor disease (TD) caused by Spiroplasma eriocheiris is the most destructive disease of the Chinese mitten crab, Eriocheir sinensis. This study attempts to construct Multienzyme Isothermal Rapid Amplification (MIRA), a quick and simple nucleic acid amplification method that operates at room temperature. Based on the gene sequences of S. eriocheiris, appropriate amplification primers were constructed and screened in this investigation. Both the relevant specific probe and the chosen specific amplification primers were designed and labeled. The MIRA and MIRA-LFD reaction conditions were then optimized. The result showed MIRA and MIRA-FFD could identify S. eriocheiris at 37 °C in 30 min and 15 min, respectively. To investigate the specificity of MIRA and MIRA-LFD, three Gram-negative bacteria (Bacillus subtilis, Bacillus thuringiensis, and Staphylococcus aureus), three Gram-positive bacteria (Escherichia coli, Aeromonas hydrophila, and Salmonella typhimurium) and S. eriocheiris were selected. The result showed MIRA and MIRA-LFD were highly specific to S. eriocheiris and did not react with other six pathogens. The sensitivities of PCR, MIRA, and MIRA-LFD were then evaluated. The result showed the detection limit of PCR is 1 ng/L whereas the detection limit of MIRA and MIRA-LFD is 10 pg/L. Finally, the established MIRA and MIRA-LFD detection methods had the advantages of being quick, sensitive, and specific for S. eriocheiris detection, as well as not requiring any specialized equipment.
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Spiroplasma , Animales , Spiroplasma/genética , Reacción en Cadena de la Polimerasa , Técnicas de Amplificación de Ácido NucleicoRESUMEN
Enterocytozoon hepatopenaei (EHP), an obligate intracellular parasite classified as microsporidia, is an emerging pathogen with a significant impact on the global shrimp aquaculture industry. The understanding of how microsporidia germinate has been a key factor in exploring its infection process. However, the germination process of EHP was rarely reported. To gain insight into the germination process, we conducted a high-throughput sequencing analysis of purified EHP spores that had undergone in vitro germination treatment. This analysis revealed 137 differentially expressed genes, with 84 up-regulated and 53 down-regulated genes. While the functions of some of the genes remain unknown, this study provides important data on the transcriptomic changes before and after EHP germination, which can aid in further studies on the EHP infection mechanism.
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Enterocytozoon , Penaeidae , Animales , Transcriptoma , Penaeidae/parasitología , Perfilación de la Expresión Génica , Enterocytozoon/genética , EsporasRESUMEN
Enterocytozoon hepatopenaei (EHP) is a microsporidian parasite that infects Litopenaeus vannamei, causing severe hepatopancreatic microsporidiosis (HPM) and resulting in significant economic losses. This study utilizes a combined analysis of transcriptomics and metabolomics to unveil the dynamic molecular interactions between EHP and its host, the Pacific white shrimp, during the early and late stages of infection. The results indicate distinct immunological, detoxification, and antioxidant responses in the early and late infection phases. During early EHP infection in shrimp, immune activation coincides with suppression of genes like Ftz-F1 and SEPs, potentially aiding parasitic evasion. In contrast, late infection shows a refined immune response with phagocytosis-enhancing down-regulation of Ftz-F1 and a resurgence in SEP expression. This phase is characterized by an up-regulated detoxification and antioxidant response, likely a defense against the accumulated effects of EHP, facilitating a stable host-pathogen relationship. In the later stages of infection, most immune responses return to baseline levels, while some immune genes remain active. The glutathione antioxidant system is suppressed early on but becomes activated in the later stages. This phenomenon could facilitate the early invasion of EHP while assisting the host in mitigating oxidative damage caused by late-stage infection. Notably, there are distinctive events in polyamine metabolism. Sustained up-regulation of spermidine synthase and concurrent reduction in spermine levels suggest a potential role of polyamines in EHP development. Throughout the infection process, significant differences in genes such as ATP synthase and hexokinase highlight the continuous influence on energy metabolism pathways. Additionally, growth-related pathways involving amino acids such as tryptophan, histidine, and taurine are disrupted early on, potentially contributing to the growth inhibition observed during the initial stages of infection. In summary, these findings elucidate the dynamic interplay between the host, Litopenaeus vannamei, and the parasite, EHP, during infection. Specific phase differences in immune responses, energy metabolism, and antioxidant processes underscore the intricate relationship between the host and the parasite. The disruption of polyamine metabolism offers a novel perspective in understanding the proliferation mechanisms of EHP. These discoveries significantly advance our comprehension of the pathogenic mechanisms of EHP and its interactions with the host.
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Enterocytozoon , Penaeidae , Animales , Antioxidantes , Enterocytozoon/genética , Alimentos Marinos , Penaeidae/genética , PoliaminasRESUMEN
Lithium-ion batteries based on single-crystal LiNi1- x - y Cox Mny O2 (NCM, 1-x-y ≥ 0.6) cathode materials are gaining increasing attention due to their improved structural stability resulting in superior cycle life compared to batteries based on polycrystalline NCM. However, an in-depth understanding of the less pronounced degradation mechanism of single-crystal NCM is still lacking. Here, a detailed postmortem study is presented, comparing pouch cells with single-crystal versus polycrystalline LiNi0.60 Co0.20 Mn0.20 O2 (NCM622) cathodes after 1375 dis-/charge cycles against graphite anodes. The thickness of the cation-disordered layer forming in the near-surface region of the cathode particles does not differ significantly between single-crystal and polycrystalline particles, while cracking is pronounced for polycrystalline particles, but practically absent for single-crystal particles. Transition metal dissolution as quantified by time-of-flight mass spectrometry on the surface of the cycled graphite anode is much reduced for single-crystal NCM622. Similarly, CO2 gas evolution during the first two cycles as quantified by electrochemical mass spectrometry is much reduced for single-crystal NCM622. Benefitting from these advantages, graphite/single-crystal NMC622 pouch cells are demonstrated with a cathode areal capacity of 6 mAh cm-2 with an excellent capacity retention of 83% after 3000 cycles to 4.2 V, emphasizing the potential of single-crystalline NCM622 as cathode material for next-generation lithium-ion batteries.
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Sodium ion batteries, because of their sustainability attributes, could be an attractive alternative to Li-ion technology for specific applications. However, it remains challenging to design high energy density and moisture stable Na-based positive electrodes. Here, we report an O3-type NaLi1/3Mn2/3O2 phase showing anionic redox activity, obtained through a ceramic process by carefully adjusting synthesis conditions and stoichiometry. This phase shows a sustained reversible capacity of 190 mAh g-1 that is rooted in cumulative oxygen and manganese redox processes as deduced by combined spectroscopy techniques. Unlike many other anionic redox layered oxides so far reported, O3-NaLi1/3Mn2/3O2 electrodes do not show discernible voltage fade on cycling. This finding, rationalized by density functional theory, sheds light on the role of inter- versus intralayer 3d cationic migration in ruling voltage fade in anionic redox electrodes. Another practical asset of this material stems from its moisture stability, hence facilitating its handling and electrode processing. Overall, this work offers future directions towards designing highly performing sodium electrodes for advanced Na-ion batteries.
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PURPOSE: The combined use of antibiotics and anti-inflammatory medicine to manage bacterial endotoxin-induced inflammation following injuries or diseases is increasing. The cytokine level produced by macrophages plays an important role in this treatment course. Ciprofloxacin and indomethacin, two typical representatives of antibiotics and anti-inflammatory medicine, are cost-effective and has been reported to show satisfactory effect. The current study aims to investigate the effect of ciprofloxacin along with indomethacin on the secretion of inflammatory cytokines by macrophages in vitro. METHODS: Primary murine peritoneal macrophages and RAW 264.7 cells were administrated with lipopolysaccharide (LPS) for 24 h. The related optimal dose and time point of ciprofloxacin or indomethacin in response to macrophage inflammatory response inflammation were determined via macrophage secretion induced by LPS. Then, the effects of ciprofloxacin and indomethacin on the secretory functions and viability of various macrophages were determined by enzyme-linked immunosorbent assay and flow cytometry analysis, especially for the levels of interleukin (IL)-1ß, IL-6, IL-10, and tumor necrosis factor (TNF)-α. The optimal dose and time course of ciprofloxacin affecting macrophage inflammatory response were determined by testing the maximum inhibitory effect of the drugs on pro-inflammatory factors at each concentration or time point. RESULTS: According to the levels of cytokines secreted by various macrophages (1.2 × 106 cells/well) after administration of 1 µg/mL LPS, the optimal dose and usage timing for ciprofloxacin alone were 80 µg/mL and 24 h, respectively, and the optimal dose for indomethacin alone was 10 µg/mL. Compared with the LPS-stimulated group, the combination of ciprofloxacin and indomethacin reduced the levels of IL-1ß (p < 0.05), IL-6 (p < 0.05), IL-10 (p < 0.01)), and TNF-α (p < 0.01). Furthermore, there was greater stability in the reduction of inflammatory factor levels in the combination group compared with those in which only ciprofloxacin or indomethacin was used. CONCLUSION: The combination of ciprofloxacin and indomethacin suppressed the levels of inflammatory cytokines secreted by macrophages in vitro. This study illustrates the regulatory mechanism of drug combinations on innate immune cells that cause inflammatory reactions. In addition, it provides a new potential antibacterial and anti-inflammatory treatment pattern to prevent and cure various complications in the future.
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Citocinas , Lipopolisacáridos , Humanos , Ratones , Animales , Lipopolisacáridos/farmacología , Interleucina-10 , Indometacina/farmacología , Indometacina/uso terapéutico , Interleucina-6/farmacología , Interleucina-6/uso terapéutico , Ciprofloxacina/farmacología , Ciprofloxacina/uso terapéutico , Macrófagos , Factor de Necrosis Tumoral alfa , Inflamación/tratamiento farmacológico , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antibacterianos/uso terapéuticoRESUMEN
The prevention and treatment strategies for traumatic infection often focus on the use of antibiotics, while eschew the combined treatment of the bacteria, their toxins, and inflammatory mediators. This might be a main reason the prognosis of wound victims has not improved. Although our previous work found that the combination of indomethacin (IND) and ciprofloxacin (CIP) could promote skin wound repair and enhance the immune function, the efficacy and safety of this strategy for severe traumatic infection-mediated complications remain unknown. Additionally, there is no study on the relevant target cells and molecular mechanisms. In this study, C57BL/6 adult male mice were modeled for severe traumatic infection, and the optimal doses of IND and CIP alone were determined. After that, the efficacy and safety of IND plus CIP in traumatic infection mice were explored. Then the differentially expressed genes of activated macrophages in this process were analysed and verified by transcriptomic methods and conventional experimental techniques. The role of a candidate signalling pathway (PI3K/Akt) in regulating macrophage function and drug combination therapy was evaluated. The results showed that IND plus CIP increased the survival rate, reduced the degree of inflammatory response, and enhanced the bacteriostatic effect in mice under traumatic infection. This combined therapy did not cause significant damage to the functions of important organs (liver, kidney, heart). In addition, IND combined with CIP induced macrophages to significantly change their expression levels of several cytokines, including interleukin (IL) -1ß, IL-6, IL-10, IL-22, IL-23A, IL-17A, IL-17F, cluster of differentiation (CD) 11b and other genes/encode proteins. Further study showed that intervention with the PI3K inhibitor LY294002 modulated the secretion function of the above-mentioned macrophages and Akt activation (phosphorylation at serine 473). IND plus CIP can regulate macrophage function through the PI3K/Akt signalling pathway and improve the prognosis of severe traumatic infected mice. This may be a new therapeutic strategy for the prevention and treatment of severe traumatic infection.
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The water-in-salt electrolytes have promoted aqueous Li-ion batteries to become one of the most promising candidates to overcome safety concerns/issues of traditional Li-ion batteries. A simple increase of Li-salt concentration in electrolytes can successfully expand the electrochemical stability window of aqueous electrolytes beyond 2 V. However, necessary stability improvements require an increase in complexity of the ternary electrolytes. Here, we have explored the effects of novel, Gemini-type ionic liquids (GILs) as a co-solvent systems in aqueous Li[TFSI] mixtures and investigated the transport properties of the resulting electrolytes, as well as their electrochemical performance. The devices containing pyrrolidinium-based GILs show superior cycling stability and promising specific capacity in the cells based on the commonly used electrode materials LTO (Li4Ti5O12) and LMO (LiMn2O4).
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OBJECTIVE: To explore the establishment of the interconvertible injury parameters of same severe blast injury in mice at plain and plateau. METHODS: A total of 157 C57BL/6 male mice were randomly divided into plain control group (8 mice), plain injury group (77 mice), plateau control group (8 mice) and plateau injury group (64 mice) according to random number table method. The mice in plateau control group and plateau blast injury group had been placed in animal experimental low-pressure oxygen chamber to simulate 4 000 meters plateau environment for 5 days in advance. Then the mice in plain blast injury group and plateau blast injury group were put into biological shock tube, respectively. Different pressures of the driving section were selected to establish the severe blast injury models in mice at plain and 4 000 meters plateau to reach approximately 70% mortality within 72 hours. The equivalent traumatic condition at 24 hours after blast injury in different groups was verified by the series of experiments including gross autopsy, lung wet/dry weight ratio (W/D), hematoxylin-eosin (HE) staining and histological scoring. RESULTS: The mice mortality were basically consistent between the plain injury group (65%) and plateau injury group (75%) when 5.4 MPa and 4.0 MPa of the driving section pressures were chosen, respectively. Compared with the corresponding control groups, the lungs showed massive hemorrhage (patchy and diffuse) with significant pulmonary edema in both plain 5.4 MPa-injured group and the plateau 4.0 MPa-injured group at 24 hours after blast injury. Compared with the plateau control group, the pulmonary W/D ratio were significantly increased in the plateau injury group (5.579±0.646 vs. 4.476±0.076, P < 0.05), while the difference between plateau injury group and the plain control group was not statistically significant (5.303±1.020 vs. 4.015±0.144, P > 0.05). Also, compared with the corresponding control groups, the analysis of lung histopathological sections showed that there were several pathological changes including large alveolar rupture and fusion, thickened alveolar walls, and a small amount of inflammatory cell infiltration in the alveolar lumen in the groups of plain 5.4 MPa and plateau 4.0 MPa. In addition, the histopathological scores of lung in the groups of plain 5.4 MPa and plateau 4.0 MPa were significantly higher than that in corresponding control group (8.67±0.82 vs. 1.67±0.52, 9.00±1.10 vs. 2.17±0.41, both P < 0.05), however, there was no statistical difference for the above score between plain blast injury group and plateau blast injury group. CONCLUSIONS: The pressures of driving section 5.4 MPa and 4.0 MPa are injury parameters to establish equivalent severe blast injury in mice at plain and plateau, respectively, which can be converted to each other. This study provides support for the application and evaluation of prevention and treatment technology for severe blast injury in special environment.
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Traumatismos por Explosión , Animales , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Ni-rich layered oxides, in a general term of Li(NixCoyMn1-x-y)O2 (x > 0.5), are widely recognized as promising candidates for improving the specific energy and lowering the cost for next-generation Li-ion batteries. However, the high surface reactivity of these materials results in side reactions during improper storage and notable gas release when the cell is charged beyond 4.3 V vs Li+/Li0. Therefore, in this study, we embark on a comprehensive investigation on the moisture sensitivity of LiNi0.85Co0.1Mn0.05O2 by aging it in a controlled environment at a constant room-temperature relative humidity of 63% up to 1 year. We quantitatively analyze the gassing of the aged samples by online electrochemical mass spectrometry and further depict plausible reaction pathways, accounting for the origin of the gas release. Transmission electron microscopy reveals formation of an amorphous surface impurity layer of ca. 10 nm in thickness, as a result of continuous reactions with moisture and CO2 from the air. Underneath it, there is another reconstructed layer of ca. 20 nm in thickness, showing rock salt/spinel-like features. Our results provide insight into the complex interfacial degradation phenomena and future directions for the development of high-performance Ni-rich layered oxides.
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Anionic redox is a double-edged sword for Li-ion cathodes because it offers a transformational increase in energy density that is also negated by several detrimental drawbacks to its practical implementation. Among them, voltage hysteresis is the most troublesome because its origin is still unclear and under debate. Herein, we tackle this issue by designing a prototypical Li-rich cation-disordered rock-salt compound Li1.17Ti0.33Fe0.5O2 that shows anionic redox activity and exceptionally large voltage hysteresis while exhibiting a partially reversible Fe migration between octahedral and tetrahedral sites. Through combined in situ and ex situ spectroscopic techniques, we demonstrate the existence of a non-equilibrium (adiabatic) redox pathway enlisting Fe3+/Fe4+ and O redox as opposed to the equilibrium (non-adiabatic) redox pathway involving sole O redox. We further show that the charge transfer from O(2p) lone pair states to Fe(3d) states involving sluggish structural distortion is responsible for voltage hysteresis. This study provides a general understanding of various voltage hysteresis signatures in the large family of Li-rich rock-salt compounds.
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High-energy-density lithium-rich materials are of significant interest for advanced lithium-ion batteries, provided that several roadblocks, such as voltage fade and poor energy efficiency are removed. However, this remains challenging as their functioning mechanisms during first cycle are not fully understood. Here we enlarge the cycling potential window for Li1.2Ni0.13Mn0.54Co0.13O2 electrode, identifying novel structural evolution mechanism involving a structurally-densified single-phase A' formed under harsh oxidizing conditions throughout the crystallites and not only at the surface, in contrast to previous beliefs. We also recover a majority of first-cycle capacity loss by applying a constant-voltage step on discharge. Using highly reducing conditions we obtain additional capacity via a new low-potential P" phase, which is involved into triggering oxygen redox on charge. Altogether, these results provide deeper insights into the structural-composition evolution of Li1.2Ni0.13Mn0.54Co0.13O2 and will help to find measures to cure voltage fade and improve energy efficiency in this class of material.
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Recent findings revealed that surface oxygen can participate in the oxygen evolution reaction (OER) for the most active catalysts, which eventually triggers a new mechanism for which the deprotonation of surface intermediates limits the OER activity. We propose in this work a "dual strategy" in which tuning the electronic properties of the oxide, such as La1-xSrxCoO3-δ, can be dissociated from the use of surface functionalization with phosphate ion groups (Pi) that enhances the interfacial proton transfer. Results show that the Pi functionalized La0.5Sr0.5CoO3-δ gives rise to a significant enhancement of the OER activity when compared to La0.5Sr0.5CoO3-δ and LaCoO3. We further demonstrate that the Pi surface functionalization selectivity enhances the activity when the OER kinetics is limited by the proton transfer. Finally, this work suggests that tuning the catalytic activity by such a "dual approach" may be a new and largely unexplored avenue for the design of novel high-performance catalysts.
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ZnFe(2)O(4)/C hollow spheres have been synthesized via a facile solvothermal route using low cost raw materials. The resulting composite showed a very high specific capacity of 841 mAh g(-1) after 30 cycles and good rate capability.