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1.
Small ; 20(1): e2304463, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37649191

RESUMEN

The high activity of water molecules results in a series of awful parasitic reaction, which seriously impede the development of aqueous zinc batteries. Herein, a new gel electrolyte with multiple molecular anchors is designed by employing natural biomaterials from chitosan and chlorophyll derivative. The gel electrolyte firmly anchors water molecules by ternary hydrogen bonding to reduce the activity of water molecules and inhibit hydrogen evolution reaction. Meanwhile, the multipolar charged functional groups realize the gradient induction and redistribution of Zn2+ , which drives oriented Zn (002) plane deposition of Zn2+ and then achieves uniform Zn deposition and dendrite-free anode. As a result, it endows the Zn||Zn cell with over 1700 h stripping/plating processes and a high efficiency of 99.4% for the Zn||Cu cell. In addition, the Zn||V2 O5 full cells also exhibit capacity retention of 81.7% after 600 cycles at 0.5 A g-1 and excellent long-term stability over 1600 cycles at 2 A g-1 , and the flexible pouch cells can provide stable power for light-emitting diodes even after repeated bending. The gel electrolyte strategy provides a reference for reversible zinc anode and flexible wearable devices.

2.
Nano Lett ; 23(12): 5722-5730, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37314735

RESUMEN

The organic electrolyte can resolve the hurdle of hydrogen evolution in aqueous electrolytes but suffers from sluggish electrochemical reaction kinetics due to a compromised mass transfer process. Herein, we introduce a chlorophyll, zinc methyl 3-devinyl-3-hydroxymethyl-pyropheophorbide-a (Chl), as a multifunctional electrolyte additive for aprotic zinc batteries to address the related dynamic problems in organic electrolyte systems. The Chl exhibits multisite zincophilicity, which significantly reduces the nucleation potential, increases the nucleation sites, and induces uniform nucleation of Zn metal with a nucleation overpotential close to zero. Furthermore, the lower LUMO of Chl contributes to a Zn-N-bond-containing SEI layer and inhibits the decomposition of the electrolyte. Therefore, the electrolyte enables repeated zinc stripping/plating up to 2000 h (2 Ah cm-2 cumulative capacity) with an overpotential of only 32 mV and a high Coulomb efficiency of 99.4%. This work is expected to enlighten the practical application of organic electrolyte systems.

3.
Nano Lett ; 22(23): 9685-9692, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36441867

RESUMEN

The practical application of Na-superionic conductor structured materials is hindered by limited energy density and structure damage upon activating the third Na+. We propose a bimetal substitution strategy with cheaper Fe and Ni elements for costive vanadium in the polyanion to improve both ionic and electronic conductivities, and a single two-phase reaction during Na+ intercalation/deintercalation and much reduced Na+ diffusion barrier are uncovered by ex-situ X-ray diffraction and density functional theory calculations. Thus, the obtained cathode, Na3Fe0.8VNi0.2(PO4)3, shows excellent electrochemical performances including high specific capacity (102.2 mAh g-1 at 0.1C), excellent rate capability (79.3 mAh g-1 at 20C), cycling stability (84.6% of capacity retention over 1400 cycles at 20C), low-temperature performance (89.7 mAh g-1 at 2C and -10 °C), and structure stability in an extended voltage window for the third Na+ utilization. A competitive energy density of ≈287 Wh kg-1 for full batteries based on cathode and anode materials is also confirmed.

4.
Molecules ; 28(10)2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37241847

RESUMEN

High-energy-density lithium metal batteries with high safety and stability are urgently needed. Designing the novel nonflammable electrolytes possessing superior interface compatibility and stability is critical to achieve the stable cycling of battery. Herein, the functional additive dimethyl allyl-phosphate and fluoroethylene carbonate were introduced to triethyl phosphate electrolytes to stabilize the deposition of metallic lithium and accommodate the electrode-electrolyte interface. In comparison with traditional carbonate electrolyte, the designed electrolyte shows high thermostability and inflaming retarding characteristics. Meanwhile, the Li||Li symmetrical batteries with designed phosphonic-based electrolytes exhibit a superior cycling stability of 700 h at the condition of 0.2 mA cm-2, 0.2 mAh cm-2. Additionally, the smooth- and dense-deposited morphology was observed on an cycled Li anode surface, demonstrating that the designed electrolytes show better interface compatibility with metallic lithium anodes. The Li||LiNi0.8Co0.1Mn0.1O2 and Li||LiNi0.6Co0.2Mn0.2O2 batteries paired with phosphonic-based electrolytes show better cycling stability after 200 and 450 cycles at the rate of 0.2 C, respectively. Our work provides a new way to ameliorate nonflammable electrolytes in advanced energy storage systems.

5.
BMC Pediatr ; 22(1): 9, 2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34980023

RESUMEN

BACKGROUND: Necrotizing enterocolitis (NEC) is a gastrointestinal disease that tends to occur in premature infants. Some features may be associated with an increased probability that preterm infants with NEC will require surgical treatment. This study aimed to identify the factors that increased the probability of surgical treatment in infants with NEC. METHODS: We retrospectively analyzed the data of premature infants with NEC who were hospitalized at The Affiliated Hospital of Qingdao University from April 2011 to April 2021. According to the treatments received, these patients were divided into medical NEC group and surgical NEC group. The perinatal characteristics, clinical manifestations, and laboratory values before the onset of NEC were subjected to univariate and multivariate analyses. RESULTS: A total of 623 preterm infants with NEC (> Bell's stage I) were included in this study, including 350 (56%) who received surgical treatment and 273 (44%) who received conservative medical treatment. Multivariate analysis showed that lower gestational age (P = 0.001, odds ratio (OR) (95% CI) = 0.91[0.86-0.96]), early occurrence of NEC (P = 0.003, OR (95% CI) = 0.86 [0.77-0.95]), hemodynamically significant patent ductus arteriosus (P = 0.003, OR (95% CI) = 7.50 [2.03-28.47]), and low serum bicarbonate (P = 0.043, OR (95% CI) = 0.863 [0.749-0.995]) were associated with an increased probability of surgical treatment in preterm infants with NEC. CONCLUSIONS: Our findings were applied to identify potential predictors for surgical treatment in preterm infants with NEC, which may facilitate early decisive management.


Asunto(s)
Conducto Arterioso Permeable , Enterocolitis Necrotizante , Enfermedades del Prematuro , Conducto Arterioso Permeable/tratamiento farmacológico , Enterocolitis Necrotizante/epidemiología , Enterocolitis Necrotizante/cirugía , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/cirugía , Embarazo , Estudios Retrospectivos
6.
Fetal Pediatr Pathol ; 41(3): 371-380, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32969743

RESUMEN

Objective: We investigated three-dimensional (3 D) reconstruction for the assessment of the tumor margin microstructure of hepatoblastoma (HB). Methods: Eleven surgical resections of childhood hepatoblastomas obtained between September 2018 and December 2019 were formalin-fixed, paraffin-embedded, serially sectioned at 4 µm, stained with hematoxylin and eosin (every 19th and 20th section stained with alpha-fetoprotein and glypican 3), and the digital images of all sections were acquired at 100× followed by image registration using the B-spline based method with modified residual complexity. Reconstruction was performed using 3 D Slicer software. Results: The reconstructed orthogonal 3 D images clearly presented the internal microstructure of the tumor margin. The rendered 3 D image could be rotated at any angle. Conclusions: Microstructure 3 D reconstruction is feasible for observing the pathological structure of the HB tumor margin.


Asunto(s)
Hepatoblastoma , Neoplasias Hepáticas , Humanos , Imagenología Tridimensional/métodos
7.
BMC Health Serv Res ; 21(1): 856, 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34419013

RESUMEN

BACKGROUND: China started to cover novel medicines for the treatment of major cancers, such as trastuzumab for breast cancer by the government health insurance programs since 2016. Limited data have been published on the use of cancer medications and little is known about how government health insurance coverage of novel anti-cancer medicines benefited patients in the real world. This study aimed to generate evidence to inform the health security authorities to optimize the government health insurance coverage of novel anti-cancer medicines as a more inclusive and equal policy, through which each of the needed patient can get access to the novel anti-cancer medicines regardless of the ability to pay. METHODS: The study targeted one of the government health insurance newly covered novel medicines for breast cancer and the breast cancer patients. The analyses were based on the data collected from one tertiary public hospital in Fujian province of China. We conducted interrupted time series analysis with a segmented regression model and multivariate analyses with a binary logistic regression model to analyze the impact of the government health insurance coverage on medicines utilization and the determinants of patient's medication choice. RESULTS: The average proportion of patients who initiated medication with novel medicines increased from 37.4% before the government health insurance coverage to 69.2% afterwards. Such an increase was observed in all patient sub-groups. The monthly proportion of patients who initiated medication with novel medicines increased sharply by 18.3 % (95 %CI,10.4-34.0 %, p = 0.01) in September 2017, the afterwards trend continuously increased (95 %CI,1.03-3.60, p = 0.02). The critical determinants of patient's medication choice were mostly connected with the patient's health insurance benefits packages. CONCLUSIONS: The government health insurance coverage of novel anti-breast-cancer medicines benefited the patients generally. The utilization of novel medicines such as trastuzumab continuously increased. The insurance coverage benefited well the patients in the high-risk age groups. However, rural patients, patients enrolled in the "resident program", and patients from low-income residential areas and non-local patients benefited less from this policy. Improving the benefits package of the low-income patients and the "resident program" beneficiary would be of considerable significance for a more inclusive and equal health insurance coverage of novel anti-cancer medicines.


Asunto(s)
Gobierno , Cobertura del Seguro , China , Hospitales , Humanos , Estudios Retrospectivos
8.
Pediatr Hematol Oncol ; 38(4): 319-330, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33667139

RESUMEN

Hepatoblastoma (HB) is the most common liver cancer in children, this study aims at analyzing the prognostic factors affecting the survival rates and summarizing the treatment experience. In this study, we reviewed patients with primary HB under the age of 14 years who underwent complete tumor resection from June 1997 to March 2019. The data of 72 patients were collected. Survival analysis was performed by Kaplan-Meier, multivariate Cox proportional hazards regression and linear mixed model for repeated measures (LMMRM). The 5-year and the 10-year event-free survival (EFS) of all patients were 78.2% and 73%, respectively. Both the 5-year and 10-year overall survival (OS) were 85.7%. Kaplan-Meier survival analysis showed that patients with tumor capsule infiltration (TCI) and patients with surgical margin less than 1 cm may also have a good prognosis. The Cox proportional hazards regression model analysis results were similar to the Kaplan-Meier analysis results. LMMRM analysis showed that there were significant differences in platelet, alpha-fetoprotein, C-reactive protein and hemoglobin values after surgery in the metastasis group (P < 0.05). This study suggests that patients with TCI or narrow surgical margin (<1 cm) may also have a good prognosis, and the risk stratification of HB can be used as the latest grading standard to evaluate the prognosis of patients.


Asunto(s)
Hepatoblastoma/epidemiología , Neoplasias Hepáticas/epidemiología , Preescolar , China/epidemiología , Supervivencia sin Enfermedad , Hepatoblastoma/diagnóstico , Hepatoblastoma/terapia , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
9.
Angew Chem Int Ed Engl ; 60(30): 16554-16560, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-33955135

RESUMEN

Rechargeable lithium-metal batteries with a cell-level specific energy of >400 Wh kg-1 are highly desired for next-generation storage applications, yet the research has been retarded by poor electrolyte-electrode compatibility and rigorous safety concerns. We demonstrate that by simply formulating the composition of conventional electrolytes, a hybrid electrolyte was constructed to ensure high (electro)chemical and thermal stability with both the Li-metal anode and the nickel-rich layered oxide cathodes. By employing the new electrolyte, Li∥LiNi0.6 Co0.2 Mn0.2 O2 cells show favorable cycling and rate performance, and a 10 Ah Li∥LiNi0.8 Co0.1 Mn0.1 O2 pouch cell demonstrates a practical specific energy of >450 Wh kg-1 . Our findings shed light on reasonable design principles for electrolyte and electrode/electrolyte interfaces toward practical realization of high-energy rechargeable batteries.

10.
Med Sci Monit ; 26: e927725, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33328429

RESUMEN

BACKGROUND Long non-coding RNA (lncRNA) can act as competing endogenous RNA (ceRNA) during tumor development. However, no study has elucidated the ceRNA network in pediatric rhabdoid tumor of the kidney (RTK) and its prognostic-related lncRNAs. The goal of the present study was to identify potential biomarkers of prognostic-related lncRNAs. MATERIAL AND METHODS RNA sequencing and clinical data were procured from the TARGET database. The "EdgeR" package was used to obtain differentially expressed lncRNA (DElncRNA), differentially expressed messenger RNAs (DEmRNA), and differentially expressed microRNAs (DEmiRNA). Cytoscape software was used to construct a ceRNA network. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted on the ceRNA network-related DEmRNA. The Kaplan-Meier method was used for predicting survival with ceRNA network-related DElncRNA. Univariate and multivariate Cox analyses were used to identify prognosis-related lncRNAs in the ceRNA network, and an RTK prognostic signature was constructed. RESULTS We identified 1109 DElncRNAs, 215 DEmiRNAs, and 3436 DEmRNAs; and 107 DElncRNAs, 21 DEmiRNAs, and 74 DEmRNAs were included in the ceRNA regulatory network. GO enrichment analysis and KEGG pathway enrichment indicated that the DEmRNAs were mainly related to the regulation of phospholipase C activity and the MAPK signaling pathway. Survival analysis showed that 9 of 107 DElncRNAs were correlated with prognosis (P<0.05). Univariate and multivariate Cox analysis identified 4 DElncRNAs (HNF1A-AS1, TPTEP1, SNHG6, and ZNF503-AS2) to establish a predictive model and can be used as independent prognostic biomarkers. CONCLUSIONS We constructed a ceRNA network that reveals potential lncRNA biomarkers for pediatric RTK.


Asunto(s)
Estimación de Kaplan-Meier , Neoplasias Renales , ARN Largo no Codificante/análisis , Tumor Rabdoide , Biomarcadores de Tumor/análisis , Niño , Bases de Datos Genéticas , Humanos , Neoplasias Renales/diagnóstico , Neoplasias Renales/genética , Pronóstico , Modelos de Riesgos Proporcionales , Proteínas Represoras , Tumor Rabdoide/diagnóstico , Tumor Rabdoide/genética
11.
BMC Surg ; 20(1): 244, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33076895

RESUMEN

BACKGROUND: Pediatric inguinal hernia (PIH) is a common disease in children. Laparoscopic hernia repair (LHR) has developed rapidly in recent years, but there are still different opinions compared with traditional open hernia repair (OHR). The purpose of this study was to compare the advantages and disadvantages of LHR and OHR in the treatment of pediatric inguinal hernia. METHODS: We performed a retrospective review of all children (< 14 years) who underwent repair of inguinal hernia in the pediatric surgery center of the Affiliated Hospital of Qingdao University from January 2015 to December 2015. We collected the medical records of all the children and analyzed the clinical characteristics, operation-related information and follow-up. RESULTS: In the OHR group, 202 cases underwent unilateral inguinal hernia repair, and 43 cases underwent bilateral inguinal hernia repair. In the LHR group, 168 cases underwent unilateral inguinal hernia repair, and 136 cases underwent bilateral inguinal hernia repair. There was a significant difference in the operation time between the two groups, but there were no significant differences in postoperative hospitalization time and incidence of ipsilateral recurrent hernia between the two groups. The incidence rates of metachronous contralateral hernia (MCH) and surgical site infection in LHR group were significantly lower than those in the OHR group. CONCLUSION: Our study shows that compared with OHR, LHR has the advantages of concealed incision, minimal invasiveness, reduced operation time, detection of contralateral patent processus vaginalis, and reduced incidence of MCH. In conclusion, LHR is safe and effective in the treatment of pediatric indirect inguinal hernia.


Asunto(s)
Hernia Inguinal/cirugía , Laparoscopía/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Niño , Preescolar , China/epidemiología , Femenino , Herniorrafia , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
12.
Angew Chem Int Ed Engl ; 59(16): 6585-6589, 2020 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-32017343

RESUMEN

A hybrid solid/liquid electrolyte with superior security facilitates the implementation of high-energy-density storage devices, but it suffers from inferior chemical compatibility with cathodes. Herein, an optimal lithium difluoro(oxalato)borate salt was introduced to build in situ an amorphous cathode electrolyte interphase (CEI) between Ni-rich cathodes and hybrid electrolyte. The CEI preserves the surface structure with high compatibility, leading to enhanced interfacial stability. Meanwhile, the space-charge layer can be prominently mitigated at the solid/solid interface via harmonized chemical potentials, acquiring promoted interfacial dynamics as revealed by COMSOL simulation. Consequently, the amorphous CEI integrates the bifunctionality to provide an excellent cycling stability, high Coulombic efficiency, and favorable rate capability in high-voltage Li-metal batteries, innovating the design philosophy of functional CEI strategy for future high-energy-density batteries.

13.
J Am Chem Soc ; 141(23): 9165-9169, 2019 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-31141357

RESUMEN

The fast-ionic-conducting ceramic electrolyte is promising for next-generation high-energy-density Li-metal batteries, yet its application suffers from the high interfacial resistance and poor interfacial stability. In this study, the compatible solid-state electrolyte was designed by coating Li1.4Al0.4Ti1.6(PO4)3 (LATP) with polyacrylonitrile (PAN) and polyethylene oxide (PEO) oppositely to satisfy deliberately the disparate interface demands. Wherein, the upper PAN constructs soft-contact with LiNi0.6Mn0.2Co0.2O2, and the lower PEO protects LATP from being reduced, guaranteeing high-voltage tolerance and improved stability toward Li-metal anode performed in one ceramic. Moreover, the core function of LATP is amplified to guide homogeneous ions distribution and hence suppresses the formation of a space-charge layer across interfaces, uncovered by the COMSOL Multiphysics concentration field simulation. Thus, such a bifunctional modified ceramic electrolyte integrates the respective superiority to render Li-metal batteries with excellent cycling stability (89% after 120 cycles), high Coulombic efficiency (exceeding 99.5% per cycle), and a dendrite-free Li anode at 60 °C, which represents an overall design of ceramic interface engineering for future practical solid battery systems.

14.
Angew Chem Int Ed Engl ; 58(4): 1094-1099, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30447094

RESUMEN

The uncontrolled growth of Li dendrites upon cycling might result in low coulombic efficiency and severe safety hazards. Herein, a lithiophilic binary lithium-aluminum alloy layer, which was generated through an in situ electrochemical process, was utilized to guide the uniform metallic Li nucleation and growth, free from the formation of dendrites. Moreover, the formed LiAl alloy layer can function as a Li reservoir to compensate the irreversible Li loss, enabling long-term stability. The protected Li electrode shows superior cycling over 1700 h in a Li|Li symmetric cell.

15.
J Am Chem Soc ; 140(22): 6767-6770, 2018 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-29775293

RESUMEN

The rapid capacity decay caused by the poor contact and large polarization at the interface between the cathode and solid electrolytes is still a big challenge to overcome for high-power-density solid batteries. In this study, a superior Li+ conductive transition layer Li1.4Al0.4Ti1.6(PO4)3 is introduced to coat LiNi0.6Co0.2Mn0.2O2, as a model cathode, to mitigate polarization and enhance dynamic characteristics. The critical attribute for such superior dynamics is investigated by the atomic force microscopy with boundary potential analysis, revealing that the formed interfacial transition layer provides a gradual potential slope and sustain-released polarization, and endows the battery with improved cycling stability (90% after 100 cycles) and excellent rate capability (116 mA h g-1 at 2 C) at room temperature, which enlightens the comprehension of interface engineering in the future solid batteries systems.

16.
Chem Soc Rev ; 46(22): 6816-6854, 2017 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-28868557

RESUMEN

Notably, many significant breakthroughs for a new generation of supercapacitors have been reported in recent years, related to theoretical understanding, material synthesis and device designs. Herein, we summarize the state-of-the-art progress toward mechanisms, new materials, and novel device designs for supercapacitors. Firstly, fundamental understanding of the mechanism is mainly focused on the relationship between the structural properties of electrode materials and their electrochemical performances based on some in situ characterization techniques and simulations. Secondly, some emerging electrode materials are discussed, including metal-organic frameworks (MOFs), covalent organic frameworks (COFs), MXenes, metal nitrides, black phosphorus, LaMnO3, and RbAg4I5/graphite. Thirdly, the device innovations for the next generation of supercapacitors are provided successively, mainly emphasizing flow supercapacitors, alternating current (AC) line-filtering supercapacitors, redox electrolyte enhanced supercapacitors, metal ion hybrid supercapacitors, micro-supercapacitors (fiber, plane and three-dimensional) and multifunctional supercapacitors including electrochromic supercapacitors, self-healing supercapacitors, piezoelectric supercapacitors, shape-memory supercapacitors, thermal self-protective supercapacitors, thermal self-charging supercapacitors, and photo self-charging supercapacitors. Finally, the future developments and key technical challenges are highlighted regarding further research in this thriving field.

17.
Heliyon ; 10(4): e26581, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38420445

RESUMEN

Neuroblastoma is a childhood cancer characterized by the formation of tumors derived from neuroblasts. Identifying the genetic mutations underlying neuroblastoma for genetic counseling and early diagnosis is essential. Thus, this study aimed to screen for pathogenic gene variants within a neuroblastoma family, aiming to contribute to genetic counseling practices. Clinical data was collected from a family affected by neuroblastoma, and peripheral blood DNA samples were obtained from all family members. A combination of whole-exome sequencing and Sanger sequencing was utilized to detect potential gene mutations. Proband 1 and her sister (Proband 2) were diagnosed with neuroblastoma, while their parents and siblings were unaffected. The analysis revealed a novel missense mutation, c.422G > A (p.Arg141Gln), in the PHOX2B gene, which was inherited from the mother. Notably, this mutation represents a previously unreported variant within the PHOX2B gene. Detecting the missense mutation c.422G > A (p.Arg141Gln) in the PHOX2B gene implies its potential pathogenic role within this neuroblastoma family. This finding widens the range of mutations observed in the PHOX2B gene and has important implications for early neuroblastoma diagnosis within this family.

18.
Chem Commun (Camb) ; 60(21): 2906-2909, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38363097

RESUMEN

A phosphoric acid additive with an optimal concentration of 0.1 M can vastly promote the diffusion kinetics of the redox reaction between V(IV) and V(V) without a significant decline in energy efficiency for 300 cycles, and maintain the high-temperature stability (55 °C) of an electrolyte at a high state of charge (SOC) of 70% over the course of 30 days.

19.
ACS Appl Mater Interfaces ; 16(25): 32189-32197, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38870428

RESUMEN

Owing to the advantages of low cost, high safety, and a desirable cycling lifetime, vanadium redox flow batteries (VRFBs) have attracted great attention in the large-scale energy storage field. However, graphite felts (GFs), widely used as electrode materials, usually possess an inferior catalytic activity for the redox reaction of vanadium ions, largely limiting the energy efficiency and rate performance of VRFBs. Here, an in situ growth of amorphous MnO2 on graphite felt (AMO@GF) was designed for application in VRFBs via mild and rapid etching engineering (5 min). After the etching process, the graphite felt fibers showed a porous and defective surface, contributing to abundant active sites toward the redox reaction. In addition, formed amorphous MnO2 can also serve as a powerful catalyst to facilitate the redox couples of VO2+/VO2+ based on density functional theoretical (DFT) calculations. As a result, the VRFB using AMO@GF displayed an elevated energy efficiency and superior stability after 2400 cycles at 200 mA cm-2, and the maximum current density can reach 300 mA cm-2. Such a high-efficiency and convenient design strategy for the electrode material will drive the further development and industrial application of VRFBs and other flow battery systems.

20.
ACS Nano ; 18(6): 5003-5016, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38294411

RESUMEN

The cycling stability of a thin zinc anode under high zinc utilization has a critical impact on the overall energy density and practical lifetime of zinc ion batteries. In this study, an ion sieve protection layer (ZnSnF@Zn) was constructed in situ on the surface of a zinc anode by chemical replacement. The ion sieve facilitated the transport and desolvation of zinc ions at the anode/electrolyte interface, reduced the zinc deposition overpotential, and inhibited side reactions. Under a 50% zinc utilization, the symmetrical battery with this protection layer maintained stable cycling for 250 h at 30 mA cm-2. Matched with high-load self-supported vanadium-based cathodes (18-20 mg cm-2), the coin battery with 50% zinc utilization possessed an energy density retention of 94.3% after 1000 cycles at 20 mA cm-2. Furthermore, the assembled pouch battery delivered a whole energy density of 61.3 Wh kg-1, surpassing the highest mass energy density among reported mild zinc batteries, and retained 76.7% of the energy density and 85.3% (0.53 Ah) of the capacity after 300 cycles.

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