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1.
Drug Des Devel Ther ; 14: 1779-1798, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440103

RESUMO

Background: Radiotherapy has an ameliorative effect on a wide variety of tumors, but hepatocellular carcinoma (HCC) is insensitive to this treatment. Overactivated mammalian target of rapamycin (mTOR) plays an important part in the resistance of HCC to radiotherapy; thus, mTOR inhibitors have potential as novel radiosensitizers to enhance the efficacy of radiotherapy for HCC. Methods: A lead compound was found based on pharmacophore modeling and molecular docking, and optimized according to the differences between the ATP-binding pockets of mTOR and PI3K. The radiosensitizing effect of the optimized compound (2a) was confirmed by colony formation assays and DNA double-strand break assays in vitro. The discovery and preclinical characteristics of this compound are described. Results: The key amino acid residues in mTOR were identified, and a precise virtual screening model was constructed. Compound 2a, with a 4,7-dihydro-[1,2,4]triazolo[1,5-a]pyrimidine scaffold, exhibited promising potency against mTOR (mTOR IC50=7.1 nmol/L (nM)) with 126-fold selectivity over PI3Kα. Moreover, 2a significantly enhanced the sensitivity of HCC to radiotherapy in vitro in a dose-dependent manner. Conclusion: A new class of selective mTOR inhibitors was developed and their radiosensitization effects were confirmed. This study also provides a basis for developing mTOR-specific inhibitors for use as radiosensitizers for HCC radiotherapy.

2.
Nat Commun ; 11(1): 2303, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385276

RESUMO

White adipose tissue (WAT) expansion in obesity occurs through enlargement of preexisting adipocytes (hypertrophy) and through formation of new adipocytes (adipogenesis). Adipogenesis results in WAT hyperplasia, smaller adipocytes and a metabolically more favourable form of obesity. How obesogenic WAT hyperplasia is induced remains, however, poorly understood. Here, we show that the mechanosensitive cationic channel Piezo1 mediates diet-induced adipogenesis. Mice lacking Piezo1 in mature adipocytes demonstrated defective differentiation of preadipocyte into mature adipocytes when fed a high fat diet (HFD) resulting in larger adipocytes, increased WAT inflammation and reduced insulin sensitivity. Opening of Piezo1 in mature adipocytes causes the release of the adipogenic fibroblast growth factor 1 (FGF1), which induces adipocyte precursor differentiation through activation of the FGF-receptor-1. These data identify a central feed-back mechanism by which mature adipocytes control adipogenesis during the development of obesity and suggest Piezo1-mediated adipocyte mechano-signalling as a mechanism to modulate obesity and its metabolic consequences.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32239909

RESUMO

A crucial challenge for the commercialization of Ni-rich layered cathodes (LiNi0.88Co0.09Al0.03O2) is capacity decay during the cycling process, which originates from their interfacial instability and structural degradation. Herein, a one-step, dual-modified strategy is put forward to in situ synthesize the yttrium (Y)-doped and yttrium orthophosphate (YPO4)-modified LiNi0.88Co0.09Al0.03O2 cathode material. It is confirmed that the YPO4 coating layer as a good ion conductor can stabilize the solid-electrolyte interface, while the formative strong Y-O bond can bridle TM-O slabs to intensify the lattice structure in the state of deep delithium (>4.3 V). In particular, both the combined advantages effectively withstand the anisotropic strain generated upon the H2-H3 phase transition and further alleviate the crack generation in unit-cell dimensions, assuring a high-capacity delivery and fast Li+ diffusion kinetics. This dual-modified cathode shows advanced cycling stability (94.1% at 1C after 100 cycles in 2.7-4.3 V), even at a high cutoff voltage and high rate, and advanced rate capability (159.7 mAh g-1 at 10C). Therefore, it provides a novel solution to achieve both high capacity and highly stable cyclability in Ni-rich cathode materials.

4.
Sci Total Environ ; 721: 137624, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32171137

RESUMO

The occurrence, partition, and human health risk of thirteen pharmaceuticals and personal care products (PPCPs) have been investigated in surface water, overlying water, pore water and sediment samples from Dianshan Lake of Yangtze River Delta Ecology and Greenery Integration Development Demonstration Zone in China. PPCPs were ubiquitous in aqueous phase and sediments from Dianshan Lake. Sulfamethazine (SMZ) was dominated in surface water and overlying water, while ketoprofen (KPF) was rich in sediment. The total concentration of PPCPs ranged from 0.38-85.27 ng/L, 24.26-130.03 ng/L and 5.39-149.84 µg/kg in surface water, overlying water and sediment, respectively, which were in middle levels compared with these reported in other aquatic environment in China. Naproxen (NPX), sulfadimethoxine (SDM), sulfamethoxazole (SMX) and sulfamethazine (SMZ) in surface water showed a relatively higher level in lake side than those in lake center suggesting that a mixed containment source of human- and animal-derived from the areas around lake. The significant season variations of most PPCPs were mainly attributed to their usage, water temperature and dilution effect. The partition behaviors of PPCPs in sediment-overlying water and sediment-pore water system were mainly affected by their logKow values, and showed weak correlation with total organic carbon (TOC) content in sediment and molecular weights of PPCPs. Preliminary results indicated that PPCPs in Dianshan Lake have not posed a high risk to human health by exposure to drinking water for all age groups. Nevertheless, their potential to cause the mixture toxicity and resistance genes cannot be neglected. This work will contribute to the clear picture of PPCPs contamination in drinking water source in the Demonstration Zone, and provide reliable and simple-to-use information to regulators on the exposure and risk levels of PPCPs, as well as recommendations for future research.

5.
Nanoscale ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32053128

RESUMO

The spatial separation of reduction and oxidation reaction sites on the different facets of a semiconductor is an ideal and promising route for overall photocatalytic water splitting due to efficient charge carrier separation. Rutile TiO2 has separate oxidation and reduction crystal facets and can be used to achieve direct splitting of pure water under ultraviolet (UV) light irradiation. In order to improve the rate of water oxidation reaction, the ratio of different crystal facets of rutile should be regulated controllably. However, the preparation of rutile TiO2 architecture has been limited by the availability of synthetic techniques. In this study, rutile TiO2 nanorods with various aspect ratios were accurately prepared in the presence of Cl- anions and H+ cations, which were found to play a crucial role in forming the morphology of rutile TiO2 nanorods. In addition, the mechanism involving the growth of rutile TiO2 nanorods with different aspect ratios is proposed. Rutile TiO2 nanorods with a high proportion of oxidative (111) facets provided higher overall water splitting reactivity.

6.
Nanoscale ; 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32096532

RESUMO

Correction for 'Effect of aspect ratios of rutile TiO2 nanorods on overall photocatalytic water splitting performance' by Bing Fu et al., Nanoscale, 2020, DOI: 10.1039/c9nr10870j.

7.
Clin Neurol Neurosurg ; 192: 105729, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32058205

RESUMO

OBJECTIVES: Rhabdomyosarcoma (RMS) involving the spine is rare. The aim of the present study is to explore the clinicopathological features, surgical treatments and outcomes of this rare disease. PATIENTS AND METHODS: Eleven patients with spinal RMS who received surgery in our institution between 2012 and 2018 were retrospectively investigated. The literature on spinal RMS was also reviewed. RESULTS: Our study consisted of 7 cases of primary RMS and 4 cases of metastatic RMS. Seven primary and one metastatic spinal RMS received radical resection, the remaining three metastatic patients received palliative resection. Eight patients died with a median survival time of 8 months. The mean value of Ki-67 positivity was 48.2 %. Literature review revealed a total of 22 previously reported cases. 54.5 % of the pooled cases of the 33 patients were under the age of 18. Of the 20 patients with primary spinal RMS, 9 cases were diagnosed as embryonal, while 6 of the 13 metastatic patients were diagnosed as alveolar. Multiple modalities, including surgery and concurrent adjuvant therapy were performed in 19 patients. The median overall survival (OS) for 28 patients with detailed follow-up information was 10 months. Radical resection offered a significant longer median OS than non-radical resection (18 vs. 6 months, p = 0.027). CONCLUSION: Spinal RMS mainly affects young patients. The embryonal form and alveolar form is the most frequent subtype for primary and metastatic spinal RMS respectively. Spinal RMS is highly aggressive with dismal prognosis. Multimodality therapies are the mainstay of treatment. Radical resection is strongly recommended in eligible patients.

9.
J Matern Fetal Neonatal Med ; 33(5): 758-767, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30001664

RESUMO

Aims: Several studies have been carried out to examine the association between cigarette smoking during pregnancy and risk of developing gestational diabetes mellitus (GDM), yet the findings are mixed. Therefore, we aimed to estimate the relationship between cigarette smoking during pregnancy and GDM risk.Material and methods: PubMed, ScienceDirect, and Cochrane Library databases were searched up to December 2017. Studies on cigarette smoking during pregnancy and GDM were retrieved. The pooled odds ratios (ORs) and their 95% confidence intervals (CIs) for highest versus lowest level of cigarette smoking were calculated using a random-effects model.Results: Compared to nonsmoking, the pooled ORs of cigarette smoking during pregnancy were 0.98 (95% CI: 0.88-1.10) for GDM. Specifically, the pooled ORs of light smoking and heavy smoking during pregnancy for GDM were 1.10 (95% CI: 0.97-1.25) and 1.02 (95% CI: 0.67-1.53), respectively.Conclusions: Our findings suggest that there is no significant association between cigarette smoking during pregnancy and risk of GDM.

10.
Macromol Biosci ; 20(2): e1900303, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31867845

RESUMO

Self-healing hydrogels as wound dressings still face challenges in infection prevention, especially in the dressing of mass wounds, due to their inflexibility and the slow formation of the protective film on the wound. Therefore, designing a spray-filming (rapid-forming) hydrogel that can serve as a bacterial barrier is of particular significance in the development of wound dressings. Here, a self-healing hydrogel based on adipic acid dihydrazide-modified gelatin (Gel-ADH) and monoaldehyde-modified sodium alginate(SA-mCHO) is prepared. Using dynamic, Schiff base bonds, the hydrogels exhibit excellent self-healing properties. Moreover, the gelation time of SA-mCHO/Gel-ADH (SG) hydrogels is shortened to 2-21 s, resulting in rapid filming by spraying the two precursor solutions. In addition, the rapid spray-filming ability might offer sufficient flexibility and rapidity for dealing with mass and irregular wounds. Notably, the bacterial barrier experiments show that the SG hydrogel films could form an effective barrier to Staphylococcus aureus and Candida albicans for 12 h. Therefore, SG hydrogels could be used in wound dressings and they show great promise in applications associated with mass and irregular traumas.

11.
Bioconjug Chem ; 31(3): 663-672, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31884782

RESUMO

Light-activated phototherapy, including photothermal and photodynamic therapy, has become a new way for spatiotemporal control and noninvasive treatment of cancer. In this study, two new organic porphyrin molecules (NI-Por and NI-ZnPor) with donor (D)-acceptor (A) structure were designed and synthesized. The donor-acceptor pairs facilitated the intermolecular electron transfer, resulting in the enhancement of near-infrared (NIR) absorbance and nonradiative heat generation. After self-assembling, the nanoparticles were formed with the size around 60 nm. Relative to that of organic molecules, the absorption of NI-Por NPs and NI-ZnPor NPs broadened and red-shifted to the near-infrared region. Moreover, the porphyrin-containing nanoparticles can generate heat and reactive oxygen species (ROS) simultaneously induced by a single laser (635 nm). The intracellular reactive oxygen species production of NI-Por NPs and NI-ZnPor NPs was confirmed using DCFH-DA as an indicator. Furthermore, the localization of NI-Por NP and NI-ZnPor NP in HeLa cells was verified by fluorescence confocal laser microscopy. The photocytoxicity of two nanoparticles against HeLa cells was evaluated through the CCK-8 method. The IC50 of NI-Por NPs and NI-ZnPor NPs upon 635 nm laser irradiation was calculated to be 6.92 µg/mL and 5.86 µg/mL, respectively. Furthermore, the PDT/PTT synergistic effect of NPs under a 635 nm laser was verified through different treatment groups in vitro. All these results demonstrated that the as-prepared porphyrin-based nanoparticles are promising nanoagents for PDT/PTT in clinic.

12.
PLoS One ; 14(12): e0226139, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31877150

RESUMO

In quantitative real-time PCR (qRT-PCR), data are normalized using reference genes, which helps to control for internal differences and reduce error among samples. In this study, the expression profiles of eight candidate housekeeping genes, 18S ribosomal (18S rRNA), elongation factor (EF1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein L10 (RPL10), ribosomal protein L17 (RPL17), histone 3 (H3), arginine kinase (AK), amd ß-Actin (ACTB), were evaluated in the parasitic wasp Cotesia chilonis in response to different temperatures. Specifically, the performance and stabilities of these genes were compared in adult wasps maintained in a growth condition at 27°C (normal storage conditions) and in adults obtained from pupae refrigerated at 4°C for five days (cold storage conditions). Data were analyzed using the ΔCt method, BestKeeper, NormFinder, and geNorm. The optimal numbers and stabilities of reference genes varied between the two temperature treatments (27°C and 4°C). In samples stored at normal developmental temperature (27°C), the requirement for normalization in response to low temperature exposures was three genes (18S, H3, AK), whereas normalization in response to high temperature exposures required only two reference genes (GAPDH, ACTB). In samples stored at cold temperature (4°C), for low temperature exposures two reference genes (RPL17, RPL10) were required for standardization, while following high temperature exposures three reference genes (18S, H3, ACTB) were needed. This study strengthens understanding of the selection of reference genes before qRT-PCR analysis in C. chilonis. The reference genes identified here will facilitate further investigations of the biological characteristics of this important parasitoid.


Assuntos
Perfilação da Expressão Gênica/normas , Genes Essenciais , Reação em Cadeia da Polimerase em Tempo Real/normas , Vespas/fisiologia , Actinas/genética , Animais , Arginina Quinase/genética , Gliceraldeído-3-Fosfato Desidrogenases/genética , Histonas/genética , Temperatura Alta , Proteínas de Insetos/genética , Fator 1 de Elongação de Peptídeos/genética , RNA Ribossômico 18S/genética , Padrões de Referência , Proteína Ribossômica L10/genética , Proteínas Ribossômicas/genética , Estresse Fisiológico , Vespas/genética
13.
14.
Sci Data ; 6(1): 219, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641130

RESUMO

As basic data, the river networks and water resources zones (WRZ) are critical for planning, utilization, development, conservation and management of water resources. Currently, the river network and WRZ of world are most obtained based on digital elevation model data automatically, which are not accuracy enough, especially in plains. In addition, the WRZ code is inconsistent with the river network, hindering the efficiency of data in hydrology and water resources research. Based on the global 90-meter DEM data combined with a large number of auxiliary data, this paper proposed a series of methods for generating river network and water resources zones, and then obtained high-precision global river network and corresponding WRZs at level 1 to 4. The dataset provides generated rivers with high prevision and more accurate position, reasonable basin boundaries especially in inland and plain area, also the first set of global WRZ at level 1 to 4 with unified code. It can provide an important basis and support for reasonable use of water resources and sustainable social development in the world.

15.
ACS Appl Mater Interfaces ; 11(43): 40022-40033, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31577125

RESUMO

The Ni-rich layered oxides are considered as a candidate of next-generation cathode materials for high energy density lithium-ion batteries; however, the finite cyclic life and poor thermostability impede their practical applications. There is often a tradeoff between structure stability and high capacity because the intrinsical instability of oxygen framework will lead to the structural transformation of Ni-rich materials. Because of the strong binding energy between the Te atom and O atom, herein a new technology of surface tellurium (Te) doping in the Ni-rich layered oxide (LiNi0.88Co0.09Al0.03O2) is proposed to settle the above predicament. Based on density function theory calculations and experiment analysis, it has been confirmed that the doped Te6+ ions are positioned in the TM layer near the oxide surface, which can constrain the TM-O slabs by strong Te-O bonds and prevent oxygen release from the surface, thus enhancing the stability of the lattice framework in deep delithium (>4.3 V). Especially, 1 wt % Te doping (Te 1%-NCA) shows the superiority in performance improvement. Furthermore, the reversibility of H2-H3 phase transition is also improved to relieve effectively the capacity decline and the structural transformations at extended cycling, which can facilitate the fast Li+ diffusion kinetic. Consequently, Te 1%-NCA cathode exhibits the improved cycling stability even at high voltages (4.5 and 4.7 V), good rate capability (159.2 mA h g-1 at 10 C), and high thermal stability (the peak temperature of 258 °C). Therefore, the appropriate Te surface doping provides a significant exploration for industrial development of the high-performance Ni-rich cathode materials with high capacity and structural stability.

16.
ACS Appl Mater Interfaces ; 11(31): 28023-28032, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31291077

RESUMO

Advanced sensing materials are in high demand for sensitive, real-time, and continuous detection of gas molecules for gas sensors, which have been becoming an effective tool for environmental monitoring and disease diagnosis. Cobalt-containing spinel oxides are promising sensing materials for the gas-sensing reaction owing to their element abundance and remarkable activity. Structural and component properties can be modulated to optimize the sensing performances by substituting Co with other transition metals. Herein, a systematic study of spinel MCo2O4 oxides (M = Mn, Ni, and Zn) toward gas sensing is presented. Results show that ZnCo2O4 materials with a multishelled hollow twin-sphere structure obtained excellent sensing performances to formaldehyde and acetone at different temperatures. The replacement of Co with Zn in the lattice improves the oxygen-chemisorbing ability, which allows new opportunities to synthesize and design highly sensitive chemical sensors.

17.
Mikrochim Acta ; 186(6): 352, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31098719

RESUMO

Interleukin-2 receptor alpha chain (also called CD25) is a tumor biomarker that is frequently expressed on the surface of hematological tumor cells. The authors describe an electrochemical immunoassay for CD25 that involves (a) enrichment of CD25 from samples by using magnetic nanospheres, and (b) utilization of DNA modulated current as the detection signal. Primary anti-CD25 antibody was immobilized onto F3O4 magnetic nanospheres to capture CD25 from samples. A polycytosine DNA sequence (dC20) was conjugated to the secondary antibody through glutaric dialdehyde via the amino groups on both antibody and the end of the DNA sequence. This leads to the formation of a sandwich structure on the magnetic spheres. dC20 is then reacted with molybdate to form redox molybdophosphate and generate electrochemical current (best measured at 0.2 V vs. Ag/AgCl) that is proportional to the concentration of CD25. The method is sensitive, selective, and has a wide linear response that extends from 1 pg.mL-1 to 1 ng.mL-1. The immunoassay was applied in a recovery test for CD25 in spiked serum samples. Graphical abstract Electrochemical immunoassay for CD25 is reported by initial enrichment of CD25 from samples with magnetic nanospheres and then utilizing DNA generated electrochemical current as detection signal.


Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais , DNA de Neoplasias/genética , Técnicas Eletroquímicas , Imunoensaio , Subunidade alfa de Receptor de Interleucina-2/análise , Técnicas de Amplificação de Ácido Nucleico , Óxido Ferroso-Férrico/química , Humanos , Fenômenos Magnéticos , Nanopartículas de Magnetita/química
18.
BMC Anesthesiol ; 19(1): 74, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092206

RESUMO

BACKGROUND: Perioperative cognitive impairment (CI) following surgeries is prevalent in geriatric surgical population aged 60 and older. This meta-analysis was designed to investigate whether the Mini-Mental State Examination (MMSE) has prognostic value on adverse outcomes in aged surgical patients. METHODS: PubMed, Cochrane, Embase and Medline through the Ovid were searched. Meta-analyses were carried out for CI versus non-cognitive impairment (NCI). Quality of evidence was assessed by the GRADE approach. RESULTS: One randomized controlled trial, two retrospective cohort trials, and 18 prospective cohort trials were included in the meta-analysis. Perioperative diagnosis of CI by the MMSE had higher rates of patients suffering from postoperative delirium (POD) [odd ratio (OR) 5.02, 95% confidence interval (CI) 3.27, 7.71, P < 0.00001], in-hospital mortality (OR 7.51, 95% CI 2.17, 26.02, P = 0.001), mortality within 1 year (OR 2.53, 95% CI 1.95,3.29, P < 0.00001). Postoperative CI patients had no extended length of stay in orthopedic [standardized mean difference (SMD) -0.10, 95% CI -0.20, 0.17, P = 0.91)] nor rehabilitation wards ((SMD, 0.04; 95% CI, - 0.23 to 0.31; P = 0.78). CONCLUSION: Older patients with perioperative CI were more likely to suffer from POD and mortality. The MMSE showed certain value on risk stratification and prognosis evaluation in geriatric surgical population. TRIAL REGISTRATION: PROSPERO CRD42018108739 .


Assuntos
Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Delírio do Despertar/diagnóstico , Delírio do Despertar/psicologia , Geriatria , Testes de Estado Mental e Demência , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/complicações , Delírio do Despertar/etiologia , Geriatria/tendências , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Estudos Retrospectivos , Resultado do Tratamento
19.
Chin Med J (Engl) ; 132(8): 928-934, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30958434

RESUMO

BACKGROUND: Positive surgical margins are independent risk factor for biochemical recurrence, local recurrence, and distant metastasis after radical prostatectomy. However, limited predictive tools are available. This study aimed to develop and validate a preoperative nomogram for predicting positive surgical margins after laparoscopic radical prostatectomy (LRP). METHODS: From January 2010 to March 2016, a total of 418 patients who underwent LRP without receiving neoadjuvant therapy at Peking University Third Hospital were retrospectively involved in this study. Clinical and pathological results of each patient were collected for further analysis. Univariable and multivariable logistic regression (backward stepwise method) were used for the nomogram development. The concordance index (CI), calibration curve analysis and decision curve analysis were used to evaluate the performance of our model. RESULTS: Of 418 patients involved in this study, 142 patients (34.0%) had a positive surgical margin on final pathology. Based on the backward selection, four variables were included in the final multivariable regression model, including the percentage of positive cores in preoperative biopsy, clinical stage, free prostate specific antigen (fPSA)/total PSA (tPSA), and age. A nomogram was developed using these four variables. The concordance index (C-index) of the nomogram was 0.722 in the development cohort and 0.700 in the bootstrap validations. The bias-corrected calibration plot showed a limited departure from the ideal line with a mean absolute error of 2.0%. In decision curve analyses, the nomogram showed net benefits in the range from 0.2 to 0.7. CONCLUSION: A nomogram to predict positive surgical margins after LRP was developed and validated, which could help urologists plan surgical procedures.


Assuntos
Laparoscopia/métodos , Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Idoso , Humanos , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Nomogramas , Curva ROC , Estudos Retrospectivos
20.
ACS Appl Mater Interfaces ; 11(18): 16556-16566, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30995007

RESUMO

The LiNi1- x- yCo xAl yO2 (NCA)-layered materials are regarded as a research focus of power lithium-ion batteries (LIBs) because of their high capacity. However, NCA materials are still up against the defects of cation mixing and surface erosion of electrolytes. Herein, a novel design strategy is proposed to obtain a heterostructured cathode material with a high-capacity LiNi0.88Co0.09Al0.03O2 layer ( R3̅ m) core and a stable LiNi0.5Mn1.5O4-like spinel ( Fd3̅ m) shell, which is prepared through spontaneous redox reaction of the precursor with KMnO4 in an alkaline solution and subsequent calcination procedure. The structure, morphology, element distribution, and electrochemical performances of the as-prepared NCA are studied by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical techniques. The results show that the LiNi0.5Mn1.5O4-like spinel ( Fd3̅ m) shell layer with a robust cubic close-packed crystal structure is uniformly adhered to the surface of the NCA and can availably suppress the side reactions with the electrolyte and surface-phase transformation, which will facilitate insertion/extraction of Li+ ions during cycling. Benefiting from the enhanced structural stability and improved kinetics, the heterostructured NCA delivers a better cycling performance. The discharge specific capacity is as high as 153.7 mA h g-1 at 10 C, and even at high charge voltage of 4.5 V, the capacity retention can still increase 11% at 1 C (200 mA g-1) after 100 cycles. Besides, the material exhibits a prominent thermal stability of 248 °C at 4.3 V. Therefore, this novel structure design strategy can contribute to the development and commercialization of high-performance cathode materials for power LIBs.

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