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1.
EMBO J ; 41(21): e110393, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36215696

RESUMO

Sirtuin 6 (SIRT6) is a deacylase and mono-ADP ribosyl transferase (mADPr) enzyme involved in multiple cellular pathways implicated in aging and metabolism regulation. Targeted sequencing of SIRT6 locus in a population of 450 Ashkenazi Jewish (AJ) centenarians and 550 AJ individuals without a family history of exceptional longevity identified enrichment of a SIRT6 allele containing two linked substitutions (N308K/A313S) in centenarians compared with AJ control individuals. Characterization of this SIRT6 allele (centSIRT6) demonstrated it to be a stronger suppressor of LINE1 retrotransposons, confer enhanced stimulation of DNA double-strand break repair, and more robustly kill cancer cells compared with wild-type SIRT6. Surprisingly, centSIRT6 displayed weaker deacetylase activity, but stronger mADPr activity, over a range of NAD+ concentrations and substrates. Additionally, centSIRT6 displayed a stronger interaction with Lamin A/C (LMNA), which was correlated with enhanced ribosylation of LMNA. Our results suggest that enhanced SIRT6 function contributes to human longevity by improving genome maintenance via increased mADPr activity and enhanced interaction with LMNA.


Assuntos
Lamina Tipo A , Sirtuínas , Idoso de 80 Anos ou mais , Humanos , Centenários , Alelos , Instabilidade Genômica
2.
Proc Natl Acad Sci U S A ; 120(45): e2313285120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37922325

RESUMO

The resolution limit of chromatin conformation capture methodologies (3Cs) has restrained their application in detection of fine-level chromatin structure mediated by cis-regulatory elements (CREs). Here, we report two 3C-derived methods, Tri-4C and Tri-HiC, which utilize multirestriction enzyme digestions for ultrafine mapping of targeted and genome-wide chromatin interaction, respectively, at up to one hundred basepair resolution. Tri-4C identified CRE loop interaction networks and quantitatively revealed their alterations underlying dynamic gene control. Tri-HiC uncovered global fine-gauge regulatory interaction networks, identifying >20-fold more enhancer:promoter (E:P) loops than in situ Hi-C. In addition to vastly improved identification of subkilobase-sized E:P loops, Tri-HiC also uncovered interaction stripes and contact domain insulation from promoters and enhancers, revealing their loop extrusion behaviors resembling the topologically associating domain boundaries. Tri-4C and Tri-HiC provide robust approaches to achieve the high-resolution interactome maps required for characterizing fine-gauge regulatory chromatin interactions in analysis of development, homeostasis, and disease.


Assuntos
Cromossomos , Genoma , Mapeamento Cromossômico/métodos , Genoma/genética , Cromatina/genética , Sequências Reguladoras de Ácido Nucleico/genética
3.
Pestic Biochem Physiol ; 196: 105586, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945223

RESUMO

Pyriproxyfen is a juvenile hormone analogue. The physiological effects of its low-concentration drift during the process of controlling agricultural and forestry pests on non-target organisms in the ecological environment are unpredictable, especially the effects on organs that play a key role in biological function are worthy of attention. The silk gland is an important organ for silk-secreting insects. Herein, we studied the effects of trace pyriproxyfen on autophagy and apoptosis of the silk gland in the lepidopteran model insect, Bombyx mori (silkworm). After treating fifth instar silkworm larvae with pyriproxyfen for 24 h, we found significant shrinkage, vacuolization, and fragmentation in the posterior silk gland (PSG). In addition, the results of autophagy-related genes of ATG8 and TUNEL assay also demonstrated that autophagy and apoptosis in the PSG of the silkworm was induced by pyriproxyfen. RNA-Seq results showed that pyriproxyfen treatment resulted in the activation of juvenile hormone signaling pathway genes and inhibition of 20-hydroxyecdysone (20E) signaling pathway genes. Among the 1808 significantly differentially expressed genes, 796 were upregulated and 1012 were downregulated. Among them, 30 genes were identified for autophagy-related signaling pathways, such as NOD-like receptor signaling pathway and mTOR signaling pathway, and 30 genes were identified for apoptosis-related signaling pathways, such as P53 signaling pathway and TNF signaling pathway. Further qRT-PCR and in vitro gland culture studies showed that the autophagy-related genes Atg5, Atg6, Atg12, Atg16 and the apoptosis-related genes Aif, Dronc, Dredd, and Caspase1 were responsive to the treatment of pyriproxyfen, with transcription levels up-regulated from 24 to 72 h. In addition, ATG5, ATG6, and Dronc genes had a more direct response to pyriproxyfen treatment. These results suggested that pyriproxyfen treatment could disrupt the hormone regulation in silkworms, promoting autophagy and apoptosis in the PSG. This study provides more evidence for the research on the damage of juvenile hormone analogues to non-target organisms or organs in the environment, and provides reference information for the scientific and rational use of juvenile hormone pesticides.


Assuntos
Bombyx , Animais , Bombyx/fisiologia , Seda/genética , Seda/metabolismo , Seda/farmacologia , Apoptose , Larva/metabolismo , Autofagia , Hormônios Juvenis/farmacologia , Hormônios Juvenis/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
5.
Small ; 17(52): e2104195, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34729918

RESUMO

The authors proposed a novel template-free strategy, urease-mediated interfacial growth of NH4 Ga(OH)2 CO3 nanotubes at 20-50 °C, to fabricate the porous Ga2 O3 nanotubes. The subtlety of the proposed strategy is all the products from urea enzymolysis are utilized in formation of NH4 Ga(OH)2 CO3 precipitates, and the key for interfacial growth of NH4 Ga(OH)2 CO3 nanotubes is the dynamic match between the rate of CO2 bubble fusion and NH4 Ga(OH)2 CO3 precipitation. The proposed strategy works well for the doped porous Ga2 O3 nanotubes. As a proof-of-concept, the porous ß-Ga2 O3 and ß-Ga2 O3 :Cr0.001 nanotubes are used as photocatalysts or co-catalysts with Pt, for H2 evolution from water splitting. The H2 evolution rate of porous ß-Ga2 O3 nanotubes reach 39.3 mmol g-1 h-1 with solar-to-hydrogen (STH) conversion efficiency of 2.11% (Hg lamp) or 498 µmol g-1 h-1 with STH of 0.03% (Xe lamp) respectively, both about 3 times of ß-Ga2 O3 nanoparticles synthesized at pH 9.0 without urease. The Cr-doping enhances the in-the-dark H2 evolution rate pre-lighted by Hg lamp, and Pt co-catalysis further elevates the H2 evolution rate, for instance, the H2 evolution rate of Pt-loaded ß-Ga2 O3 :Cr0.001 nanotubes reaches 54.7 mmol g-1 h-1 with STH of 2.94% under continuous lighting of Hg lamp and 1062 µmol g-1 h-1 in-the-dark.


Assuntos
Carbonatos , Gálio , Hidrogênio , Nanotubos , Urease , Catálise , Porosidade
6.
Angew Chem Int Ed Engl ; 59(40): 17472-17476, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32597549

RESUMO

Sulfide solid electrolytes are promising inorganic solid electrolytes for all-solid-state batteries. Despite their high ionic conductivity and desirable mechanical properties, many known sulfide solid electrolytes exhibit poor air stability. The spontaneous hydrolysis reactions of sulfides with moisture in air lead to the release of toxic hydrogen sulfide and materials degradation, hindering large-scale manufacturing and applications of sulfide-based solid-state batteries. In this work, we systematically investigate the hydrolysis and reduction reactions in Li- and Na-containing sulfides and chlorides by applying thermodynamic analyses based on a first principles computation database. We reveal the stability trends among different chemistries and identify the effect of cations, anions, and Li/Na content on moisture stability. Our results identify promising materials systems to simultaneously achieve desirable moisture stability and electrochemical stability, and provide the design principles for the development of air-stable solid electrolytes.

7.
Kidney Int ; 95(2): 455-466, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30471880

RESUMO

Mitochondrial diseases represent a significant clinical challenge. Substantial efforts have been devoted to identifying therapeutic strategies for mitochondrial disorders, but effective interventions have remained elusive. Recently, we reported attenuation of disease in a mouse model of the human mitochondrial disease Leigh syndrome through pharmacological inhibition of the mechanistic target of rapamycin (mTOR). The human mitochondrial disorder MELAS/MIDD (Mitochondrial Encephalopathy with Lactic Acidosis and Stroke-like Episodes/Maternally Inherited Diabetes and Deafness) shares many phenotypic characteristics with Leigh syndrome. MELAS/MIDD often leads to organ failure and transplantation and there are currently no effective treatments. To examine the therapeutic potential of mTOR inhibition in human mitochondrial disease, four kidney transplant recipients with MELAS/MIDD were switched from calcineurin inhibitors to mTOR inhibitors for immunosuppression. Primary fibroblast lines were generated from patient dermal biopsies and the impact of rapamycin was studied using cell-based end points. Metabolomic profiles of the four patients were obtained before and after the switch. pS6, a measure of mTOR signaling, was significantly increased in MELAS/MIDD cells compared to controls in the absence of treatment, demonstrating mTOR overactivation. Rapamycin rescued multiple deficits in cultured cells including mitochondrial morphology, mitochondrial membrane potential, and replicative capacity. Clinical measures of health and mitochondrial disease progression were improved in all four patients following the switch to an mTOR inhibitor. Metabolomic analysis was consistent with mitochondrial function improvement in all patients.


Assuntos
Surdez/cirurgia , Diabetes Mellitus Tipo 2/cirurgia , Rejeição de Enxerto/prevenção & controle , Imunossupressores/farmacologia , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Síndrome MELAS/cirurgia , Doenças Mitocondriais/cirurgia , Adulto , Aloenxertos/citologia , Aloenxertos/efeitos dos fármacos , Aloenxertos/patologia , Animais , Inibidores de Calcineurina/farmacologia , Inibidores de Calcineurina/uso terapêutico , Células Cultivadas , Surdez/complicações , Surdez/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Progressão da Doença , Feminino , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Humanos , Imunossupressores/uso terapêutico , Rim/citologia , Rim/efeitos dos fármacos , Rim/patologia , Falência Renal Crônica/etiologia , Falência Renal Crônica/patologia , Síndrome MELAS/complicações , Síndrome MELAS/patologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Pessoa de Meia-Idade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Doenças Mitocondriais/complicações , Doenças Mitocondriais/patologia , Cultura Primária de Células , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/imunologia , Resultado do Tratamento
8.
Med Sci Monit ; 25: 7480-7487, 2019 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-31587012

RESUMO

BACKGROUND The choice of optimal internal fixation device for distal tibial fractures remains controversial. The purpose of our study was to evaluate the effectiveness and safety of open reduction and internal fixation, minimally invasive percutaneous osteosynthesis, and intramedullary nailing of distal tibial fractures in adults using network meta-analysis of data from clinical trials. MATERIAL AND METHODS The studies were abstracted from MEDLINE, EMBASE, CNKI, and the Cochrane Central Register of Controlled Trials. Randomized controlled trials meeting inclusion and exclusion criteria were selected. Statistical analyses were conducted using Stata software, version 13.0 (Stata Corporation, College Station, Texas, USA). RESULTS Eleven randomized controlled trials were included. The total number of participants was 710 and the studies were published between 2005 and 2017. There were no significant differences in rates of delayed union, nonunion, or malunion among the various treatments (all p>0.05). The intramedullary nailing group had a lower incidence of wound complications than did the open reduction and internal fixation group and minimally invasive percutaneous osteosynthesis technique group. The SUCRA probabilities were 28.6% for ORIF, 98.4% for IMN, and 22.9% for MIPPO. CONCLUSIONS Given the superior results for intramedullary nailing in terms of wound complications, we recommend this procedure for treatment of distal tibial fractures. More RCTs focused on distal tibial fractures are needed to support the current evidence.


Assuntos
Fixação Interna de Fraturas/métodos , Fixação Intramedular de Fraturas/métodos , Redução Aberta/métodos , Fraturas da Tíbia/cirurgia , Adulto , Pinos Ortopédicos , Placas Ósseas , Feminino , Consolidação da Fratura , Fraturas Ósseas/cirurgia , Humanos , Fixadores Internos , Masculino , Pessoa de Meia-Idade , Metanálise em Rede , Tíbia/cirurgia , Resultado do Tratamento
9.
J Am Chem Soc ; 138(37): 12258-62, 2016 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-27570205

RESUMO

All-solid-state Li-batteries using solid-state electrolytes (SSEs) offer enhanced safety over conventional Li-ion batteries with organic liquid electrolytes due to the nonflammable nature of SSEs. The superior mechanical strength of SSEs can also protect against Li dendrite penetration, which enables the use of the highest specific capacity (3861 mAh/g) and lowest redox potential (-3.04 V vs standard hydrogen electrode) anode: Li metal. However, contact between the Li metal and SSEs presents a major challenge, where a large polarization occurs at the Li metal/SSE interface. Here, the chemical properties of a promising oxide-based SSE (garnet) changed from "super-lithiophobicity" to "super-lithiophilicity" through an ultrathin coating of amorphous Si deposited by plasma-enhanced chemical vapor deposition (PECVD). The wettability transition is due to the reaction between Li and Si and the in situ formation of lithiated Si. As a result, symmetric cells composed of a Si-coated garnet-structured SSE and Li metal electrodes exhibited much smaller impedance and excellent stability upon plating/stripping cycles compared to cells using bare garnet SSE. Specifically, the interfacial resistance between Li and garnet dramatically decreased from 925 to 127 Ω cm(2) when lithiated Si was formed on the garnet. Our discovery of switchable lithiophobic-lithiophilic surfaces to improve the Li metal/SSE interface opens opportunities for improving many other SSEs.

10.
Nano Lett ; 15(9): 5755-63, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26288360

RESUMO

The development of sodium ion batteries (NIBs) can provide an alternative to lithium ion batteries (LIBs) for sustainable, low-cost energy storage. However, due to the larger size and higher m/e ratio of the sodium ion compared to lithium, sodiation reactions of candidate electrodes are expected to differ in significant ways from the corresponding lithium ones. In this work, we investigated the sodiation mechanism of a typical transition metal-oxide, NiO, through a set of correlated techniques, including electrochemical and synchrotron studies, real-time electron microscopy observation, and ab initio molecular dynamics (MD) simulations. We found that a crystalline Na2O reaction layer that was formed at the beginning of sodiation plays an important role in blocking the further transport of sodium ions. In addition, sodiation in NiO exhibits a "shrinking-core" mode that results from a layer-by-layer reaction, as identified by ab initio MD simulations. For lithiation, however, the formation of Li antisite defects significantly distorts the local NiO lattice that facilitates Li insertion, thus enhancing the overall reaction rate. These observations delineate the mechanistic difference between sodiation and lithiation in metal-oxide conversion materials. More importantly, our findings identify the importance of understanding the role of reaction layers on the functioning of electrodes and thus provide critical insights into further optimizing NIB materials through surface engineering.

11.
Org Biomol Chem ; 13(9): 2566-9, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25614288

RESUMO

An efficient and general Fe(OTf)3-mediated oxidative coupling method was developed for the synthesis of doubly or triply linked porphyrin dimers. Besides the central metal and peripheral substituent, regioselectivity of the oxidative coupling was found to be closely relevant to the onset oxidation potential of the porphyrin substrate, and the reactant with higher E(onset(ox)) tends to generate meso-ß doubly fused porphyrin dimer.

12.
Biochim Biophys Acta ; 1833(12): 3338-3345, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24050918

RESUMO

From the surrounding shell to the inner machinery, nuclear proteins provide the functional plasticity of the nucleus. This study highlights the nuclear association of Pore membrane (POM) protein NDC1 and Werner protein (WRN), a RecQ helicase responsible for the DNA instability progeria disorder, Werner Syndrome. In our previous publication, we connected the DNA damage sensor Werner's Helicase Interacting Protein (WHIP), a binding partner of WRN, to the NPC. Here, we confirm the association of the WRN/WHIP complex and NDC1. In established WRN/WHIP knockout cell lines, we further demonstrate the interdependence of WRN/WHIP and Nucleoporins (Nups). These changes do not completely abrogate the barrier of the Nuclear Envelope (NE) but do affect the distribution of FG Nups and the RAN gradient, which are necessary for nuclear transport. Evidence from WRN/WHIP knockout cell lines demonstrates changes in the processing and nucleolar localization of lamin B1. The appearance of "RAN holes" void of RAN corresponds to regions within the nucleolus filled with condensed pools of lamin B1. From WRN/WHIP knockout cell line extracts, we found three forms of lamin B1 that correspond to mature holoprotein and two potential post-translationally modified forms of the protein. Upon treatment with topoisomerase inhibitors lamin B1 cleavage occurs only in WRN/WHIP knockout cells. Our data suggest the link of the NDC1 and WRN as one facet of the network between the nuclear periphery and genome stability. Loss of WRN complex leads to multiple alterations at the NPC and the nucleolus.


Assuntos
Lamina Tipo B/metabolismo , Poro Nuclear/metabolismo , Síndrome de Werner/metabolismo , Animais , Western Blotting , Galinhas , Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Imunofluorescência , Técnicas de Inativação de Genes , Proteínas de Membrana/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Ligação Proteica
13.
J Org Chem ; 79(3): 1184-91, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24428599

RESUMO

A practical method for the preparation of novel tripodal tris(porphyrinato-urea) TP3 1 was readily achieved. Because of its appreciable preorganized triangular cone-shaped cavity resulting from the intramolecular hydrogen bonds of the tripodal tris-urea backbone, this porphyrin trimer host was found to have a high affinity toward fullerenes to form stable inclusion complexes in solution. A 120-fold binding selectivity toward C70 (Kassoc = 1.81 × 10(7) M(­1)) over C60 (Kassoc = 1.51 × 10(5) M(­1)) was further achieved in toluene. Moreover, the dissociation of such inclusion complexes can be easily realized by introducing H2PO4(­), and recapturing of the fullerene can be achieved after withdrawing H2PO4(­) by Ca(2+). A recyclable process for the inclusion and release of fullerene was therefore built by alternately feeding H2PO4(­) and Ca(2+). Benefiting from this approach, TP3 1 was sequentially applied to isolate C70 from the C60-enriched fullerene mixture successfully.


Assuntos
Fulerenos/química , Íons/química , Porfirinas/química , Soluções/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares
14.
J Org Chem ; 79(22): 10988-98, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25343572

RESUMO

A metal-free oxidative cycloaddition reaction of substituted benzamides and alkynes has been developed for the synthesis of isoquinolones by using bis(trifluoracetoxy)iodobenzene (PIFA) and trifluoroacetic acid (TFA). Under mild conditions, a wide variety of isoquinolones were conveniently prepared via oxidative annulation of simple N-methoxybenzamide and diarylacetylene or aryl/alkyl acetylene derivatives in yields up to 87%.


Assuntos
Alcinos/química , Iodo/química , Iodobenzenos/química , Isoquinolinas/química , Isoquinolinas/síntese química , Metais/química , Ácido Trifluoracético/química , Catálise , Reação de Cicloadição , Estrutura Molecular , Oxirredução
15.
Org Biomol Chem ; 12(36): 6990-3, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-25113737

RESUMO

A simple and efficient method has been developed for the switchable synthesis of directly linked meso-brominated Ni(II) porphyrin dimers through PIFA-BF3·Et2O mediated oxidative coupling. The respective syntheses of meso-meso or meso-ß singly, doubly, and triply linked porphyrin dimers can be easily realized with the same reagent system.

16.
Int J Biol Macromol ; 280(Pt 1): 135697, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39288861

RESUMO

The FecBB mutation, a single-point mutation (c.A746G; p.Q249R) in bone morphogenetic protein receptor type 1 B (BMPR1B), is associated with increased ovulation quotas and litter size in sheep. However, the regulatory mechanism of the FecBB mutation in increased fecundity remains to be elucidated. Therefore, creating an immortal cell model harboring the FecBB mutation would elucidate the regulatory mechanism of this mutation. Here, we report the creation of a human granulosa cell, COV434, model containing a homozygous FecBB mutation through homology-directed repair (HDR) induced by clustered, regularly-interspaced, short palindromic repeats-CRISPR-associated protein 9 along with a single-stranded oligodeoxynucleotide (ssODN) template. We found that the FecBB mutation enhanced the basal SMAD1/5 signaling activity in COV434 cells, leading to increased expression of FSHR, probably through increased formation of the SMAD1/5-SMAD4 complex to bind to the SBE element, which in turn promotes the binding of USF1 to the regulatory element E-box in the promoter of FSHR. Furthermore, the FecBB mutation substantially enhanced estradiol (E2) synthesis in granulosa cells under follicle stimulating hormone (FSH) stimulation, indicating an enhanced sensitivity to FSH, which may promote the growth of more small follicles into mature follicles, leading to increased fecundity. Our study provides novel insights into the possible regulatory mechanisms of FecBB mutations in increased fecundity.

17.
Int J Biol Macromol ; 279(Pt 4): 135509, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39255881

RESUMO

Hydrogel-based flexible sensors have garnered considerable interest in the fields of soft electronics, robotics, and human-machine interfaces. For better practical applications, integrating multiple properties-such as self-adhesive, anti-freeze, anti-volatile, self-healing, and antibacterial-into a single gel for flexible sensors remains a challenge. In this paper, a multifunctional lignin-based polyvinyl alcohol gel, containing dynamic covalent bonds, hydrogen bonds, and coordination bonds, is constructed by a simple one-pot method, in which ethylene glycol/water chosen as a binary solvent and KI as a conductive medium. The resulting organogel exhibits self-healing, long-lasting adhesion, UV shielding, antibacterial properties, excellent frost resistance (-20 °C), and volatile resistance properties. In addition, the organogel-based sensor demonstrates satisfactory sensitivity in detecting joint movements and facial expressions. This study provides a new strategy for developing a versatile flexible sensor through the introduction of renewable and bio-based lignin, promising applications in the fields of wearable electronics.

18.
Adv Mater ; : e2407519, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090700

RESUMO

Layered sodium-ion oxides hold considerable promise in achieving high-performance sodium-ion batteries. However, the notorious phase transformation during charging, attributed to increased O2-─O2- repulsion, results in substantial performance decay. Here, a hierarchical layer modification strategy is proposed to stabilize interlayer repulsion. During desodiation, migrated Li+ from the transition metal layer and anchored Ca2+ in sodium sites maintain the cationic content within the sodium layer. Meanwhile, partial oxygen substitution by fluorine and the involvement of oxygen in redox reactions increase the average valence of the oxygen layer. This sustained cation presence and elevated anion valence collectively mitigate increasing O2-─O2- repulsion during sodium extraction, enabling the Na0.61Ca0.05[Li0.1Ni0.23Mn0.67]O1.95F0.05 (NCLNMOF) cathode to retain a pure P2-type structure across a wide voltage range. Unexpected insights reveal the interplay between different doping elements: the robust Li─F bonds and Ca2+ steric effects suppressing Li+ loss. The NCLNMOF electrode exhibits 82.5% capacity retention after 1000 cycles and a high-rate capability of 94 mAh g-1 at 1600 mA g-1, demonstrating the efficacy of hierarchical layer modification for high-performance layered oxide cathodes.

19.
ACS Nano ; 18(28): 18368-18378, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38970500

RESUMO

All-solid-state batteries (ASSBs) have garnered considerable attention as promising candidates for next-generation energy storage systems due to their potentially simultaneously enhanced safety capacities and improved energy densities. However, the solid future still calls for materials with high ionic conductivity, electrochemical stability, and favorable interfacial compatibility. In this study, we present a series of halide solid-state electrolytes (SSEs) utilizing a doping strategy with highly valent elements, demonstrating an outstanding combination of enhanced ionic conductivity and oxidation stability. Among these, Li2.6In0.8Ta0.2Cl6 emerges as the standout performer, displaying a superionic conductivity of up to 4.47 mS cm-1 at 30 °C, along with a low activation energy barrier of 0.321 eV for Li+ migration. Additionally, it showcases an extensive oxidation onset of up to 5.13 V (vs Li+/Li), enabling high-voltage ASSBs with promising cycling performance. Particularly noteworthy are the ASSBs employing LiCoO2 cathode materials, which exhibit an extended cyclability of over 1400 cycles, with 70% capacity retention under 4.6 V (vs Li+/Li), and a capacity of up to 135 mA h g-1 at a 4 C rate, with the loading of active materials at 7.52 mg cm-2. This study demonstrates a feasible approach to designing desirable SSEs for energy-dense, highly stable ASSBs.

20.
J Phys Chem Lett ; 14(1): 267-272, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36595354

RESUMO

Light-induced phase segregation in mixed halide perovskites is a major roadblock for commercialization of optoelectronics utilizing these materials. We investigate the phenomenon in a model material system consisting of only surfaces and the bulk of a single-crystalline-like microplate. We utilize environmental in-situ time-dependent photoluminescence spectroscopy to observe the bandgap evolution of phase segregation under illumination. This enables analysis of the evolution of the iodide-rich phase composition as a function of the environment (i.e., surface defects) and carrier concentration. Our study provides microscopic insights into the relationship among photocarrier generations, surface structural defects, and subsequently iodide ion migrations that result in the complex evolution of phase segregation. We elucidate the significance of surface defects with respect to the evolution of phase segregation, which may provide new perspectives for modulating ion migration by engineering of defects and carrier concentrations.

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