Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 241
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Chem Soc Rev ; 53(8): 4230-4301, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38477330

RESUMEN

Sodium-ion batteries (SIBs) are experiencing a large-scale renaissance to supplement or replace expensive lithium-ion batteries (LIBs) and low energy density lead-acid batteries in electrical energy storage systems and other applications. In this case, layered oxide materials have become one of the most popular cathode candidates for SIBs because of their low cost and comparatively facile synthesis method. However, the intrinsic shortcomings of layered oxide cathodes, which severely limit their commercialization process, urgently need to be addressed. In this review, inherent challenges associated with layered oxide cathodes for SIBs, such as their irreversible multiphase transition, poor air stability, and low energy density, are systematically summarized and discussed, together with strategies to overcome these dilemmas through bulk phase modulation, surface/interface modification, functional structure manipulation, and cationic and anionic redox optimization. Emphasis is placed on investigating variations in the chemical composition and structural configuration of layered oxide cathodes and how they affect the electrochemical behavior of the cathodes to illustrate how these issues can be addressed. The summary of failure mechanisms and corresponding modification strategies of layered oxide cathodes presented herein provides a valuable reference for scientific and practical issues related to the development of SIBs.

2.
Nano Lett ; 24(32): 9793-9800, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39087649

RESUMEN

O3-type layered oxides have been extensively studied as cathode materials for sodium-ion batteries due to their high reversible capacity and high initial sodium content, but they suffer from complex phase transitions and an unstable structure during sodium intercalation/deintercalation. Herein, we synthesize a high-entropy O3-type layered transition metal oxide, NaNi0.3Cu0.05Fe0.1Mn0.3Mg0.05Ti0.2O2 (NCFMMT), by simultaneously doping Cu, Mg, and Ti into its transition metal layers, which greatly increase structural entropy, thereby reducing formation energy and enhancing structural stability. The high-entropy NCFMMT cathode exhibits significantly improved cycling stability (capacity retention of 81.4% at 1C after 250 cycles and 86.8% at 5C after 500 cycles) compared to pristine NaNi0.3Fe0.4Mn0.3O2 (71% after 100 cycles at 1C), as well as remarkable air stability. Finally, the NCFMMT//hard carbon full-cell batteries deliver a high initial capacity of 103 mAh g-1 at 1C, with 83.8 mAh g-1 maintained after 300 cycles (capacity retention of 81.4%).

3.
Small ; 20(36): e2311770, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38794870

RESUMEN

Developing low-cost and highly efficient bifunctional catalysts for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) is a challenging problem in electrochemical overall water splitting. Here, iron, tungsten dual-doped nickel sulfide catalyst (Fe/W-Ni3S2) is synthesized on the nickel foam, and it exhibits excellent OER and HER performance. As a result, the water electrolyze based on Fe/W-Ni3S2 bifunctional catalyst illustrates 10 mA cm-2 at 1.69 V (without iR-compensation) and highly durable overall water splitting over 100 h tested under 500 mA cm-2. Experimental results and DFT calculations indicate that the synergistic interaction between Fe doping and Ni vacancy induced by W leaching during the in situ oxidation process can maximize exposed OER active sites on the reconstructed NiOOH species for accelerating OER kinetics, while the Fe/W dual-doping optimizes the electronic structure of Fe/W-Ni3S2 and the binding strength of intermediates for boosting HER. This study unlocks the different promoting mechanisms of incorporating Fe and W for boosting the OER and HER activity of Ni3S2 for water splitting, which provides significant guidance for designing high-performance bifunctional catalysts for overall water splitting.

4.
Rev Cardiovasc Med ; 25(5): 166, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-39076502

RESUMEN

Background: Postoperative atrial fibrillation (POAF) is a frequent complication of heart surgery, prolonging hospital stays, as well as increasing morbidity and mortality rates. While previous studies have investigated the determinants influencing atrial fibrillation (AF) following heart surgery, the specific risk factors contributing to POAF occurrence after coronary artery bypass graft surgery (CABG) are not well understood. Here we used the human magnetic Luminex assay to assess whether biomarkers, particularly cytokines, within intraoperative pericardial fluid could serve as predictive markers for POAF onset among CABG individuals. Methods: In this study we identified 180 patients who underwent CABG with no atrial arrhythmia history. The human magnetic Luminex assay was used to quantify the levels of 36 cytokines in pericardial fluid samples collected during the surgery. The occurrence of POAF was continuously monitored, using both postoperative electrocardiograms and telemetry strips, until the time of discharge. Results: In our cohort of 124 patients, POAF was observed in 30 patients, accounting for 24.19% of the study population. These patients exhibited significantly higher levels of interleukin (IL)-12p70 in their intraoperative pericardial fluids compared to those with normal sinus rhythms (SR, p < 0.001). Subsequently, IL-12p70 was found to be an independent risk factor for POAF, and receiver operating characteristic (ROC) analysis established a cut-off threshold for predicting POAF onset of 116.435 pg/mL, based on the maximum Youden index (area under the curve: 0.816). Conclusions: this study establishes a significant association between elevated IL-12p70 levels in intraoperative pericardial fluid and the risk of POAF, particularly when IL-12p70 concentrations exceed the identified cut-off value of 116.435 pg/mL. These findings suggest that IL-12p70 levels could potentially be utilized as a predictive biomarker for the onset of POAF in patients undergoing CABG. This marker may aid in the early identification and management of patients at heightened risk for this complication.

5.
Rev Cardiovasc Med ; 25(3): 98, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39076932

RESUMEN

Background: Postoperative atrial fibrillation (POAF) has long been associated with poor perioperative outcomes after coronary artery bypass grafting (CABG). In this study, we aimed to investigate the effect of prolonged POAF durations on perioperative outcomes of CABG. Methods: This retrospective cohort study examined CABG patients enrolled at Beijing Anzhen Hospital from January 2018 to September 2021. We compared patients with POAF durations ≥ 48 hours to patients with POAF durations < 48 hours. Primary outcomes were in-hospital mortality, stroke, acute respiratory failure (ARF), acute kidney injury (AKI), and significant gastrointestinal bleeding (GIB); secondary outcomes were postoperative length of stay (LOS) and intensive care unit (ICU) duration. Associations between primary outcomes and POAF duration were determined using logistic regression and restricted cubic spline analyses. Differences in baseline characteristics were controlled using propensity score matching (PSM) and inverse probability of treatment weighting (IPTW). Results: Out of 11,848 CABG patients, 3604 (30.4%) had POAF, while 1131 (31.4%) had it for a duration of ≥ 48 hours. ARF (adjusted odds ratio [OR]: 2.96, 95% confidence interval [CI]: 1.47-6.09), AKI (adjusted OR: 2.37, 95% CI: 1.42-3.99), and significant GIB (adjusted OR: 2.60, 95% CI: 1.38-5.03) were associated with POAF durations ≥ 48 hours; however, neither in-hospital mortality (adjusted OR: 1.60, 95% CI: 0.97-2.65) nor stroke (adjusted OR: 1.28, 95% CI: 0.71-2.34) was. These results remained even following PSM and IPTW analyses. Conclusions: POAF durations longer than 48 hours were independently associated with poorer perioperative recovery from CABG, with respect to the occurrence of ARF, AKI, and GIB, as well as a longer postoperative LOS and ICU duration. However, it was not associated with greater in-hospital mortality or stroke occurrence. All these findings suggest that postoperative monitoring of POAF and positive intervention after detection may be more helpful in optimizing post-CABG patient outcomes.

6.
Chemistry ; 30(55): e202304106, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39083260

RESUMEN

Sodium-oxygen batteries have been regarded as promising energy storage devices due to their low overpotential and high energy density. Its applications, however, still face formidable challenges due to the lack of understanding about the influence of electrocatalysts on the discharge products. Here, a phosphorous and nitrogen dual-doped carbon (PNDC) based cathode is synthesized to increase the electrocatalytic activity and to stabilize the NaO2 superoxide nanoparticle discharge products, leading to enhanced cycling stability when compared to the nitrogen-doped carbon (NDC). The PNDC air cathode exhibits a low overpotential (0.36 V) and long cycling stability (120 cycles). The reversible formation/decomposition and stabilization of the NaO2 discharge products are clearly proven by in-situ synchrotron X-ray diffraction and ex-situ X-ray diffraction. Based on the density functional theory calculation, the PNDC has much stronger adsorption (-2.85 eV) for NaO2 than that of NDC (-1.80 eV), which could efficiently stabilize the NaO2 discharge products.

7.
Nano Lett ; 23(13): 6050-6058, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37367972

RESUMEN

Aqueous zinc (Zn) batteries have been regarded as an alternative to lithium-ion batteries due to their high abundance, low cost, and higher intrinsic safety. However, the low Zn plating/stripping reversibility, Zn dendrite growth, and continuous water consumption have hindered the practical application of aqueous Zn anodes. Herein, a hydrous organic Zn-ion electrolyte based on a dual organic solvent, namely hydrated Zn(BF4)2 zinc salt dissolved in dimethyl carbonate (DMC) and vinyl carbonate (EC) solvents [denoted as Zn(BF4)2/DMC/EC], can address these problems, which not only inhibits the side reactions but also promotes uniform Zn plating/stripping through the formation of a stable solid state interface layer and Zn2+-EC/2DMC pairs. This electrolyte enables the Zn electrode to stably undergo >700 cycles at a rate of 1 mA cm-2 with a Coulombic efficiency of 99.71%. Moreover, the full cell paired with V2O5 also demonstrates excellent cycling stability without capacity decay at 1 A g-1 after 1600 cycles.

8.
Angew Chem Int Ed Engl ; 63(30): e202405209, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38712643

RESUMEN

Regulating the electric double layer (EDL) structure of the zinc metal anode by using electrolyte additives is an efficient way to suppress interface side reactions and facilitate uniform zinc deposition. Nevertheless, there are no reports investigating the proactive design of EDL-regulating additives before the start of experiments. Herein, a functional group assembly strategy is proposed to design electrolyte additives for modulating the EDL, thereby realizing a long-lasting zinc metal anode. Specifically, by screening ten common functional groups, N, N-dimethyl-1H-imidazole-1-sulfonamide (IS) is designed by assembling an imidazole group, characterized by its high adsorption capability on the zinc anode, and a sulfone group, which exhibits strong binding with Zn2+ ions. Benefiting from the adsorption functionalization of the imidazole group, the IS molecules occupy the position of H2O in the inner Helmholtz layer of the EDL, forming a molecular protective layer to inhibit H2O-induced side reactions. Meanwhile, the sulfone group in IS, acting as a binding site to Zn2+, promotes the de-solvation of Zn2+ ions, facilitating compact zinc deposition. Consequently, the utilization of IS significantly extending the cycling stability of Zn||Zn and Zn||NaV3O8 ⋅ 1.5H2O full cell. This study offers an innovative approach to the design of EDL regulators for high-performance zinc metal batteries.

9.
Biochem Biophys Res Commun ; 665: 124-132, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37156050

RESUMEN

Fibrillin 1 (Fbn1) mutations cause Marfan syndrome (MFS), with aortic root dilatation, dissection, and rupture. Few studies reported the blood calcium and lipid profile of MFS, and the effect of vascular smooth muscle cell (VSMC) phenotypic switching on MFS aortic aneurysm is unclear. Here, we aimed to investigate the role of calcium-related VSMC phenotypic switching in MFS. We retrospectively collected MFS patients' clinical data, performed bioinformatics analysis to screen the enriched biological process in MFS patients and mice, and detected markers of VSMC phenotypic switching on Fbn1C1039G/+ mice and primary aortic vascular smooth muscle cells. We found that patients with MFS have elevated blood calcium levels and dyslipidemia. Furthermore, the calcium concentration levels were increased with age in MFS mice, accompanied by the promoted VSMC phenotypic switching, and SERCA2 contributed to maintaining the contractile phenotype of VSMCs. This study provides the first evidence that the increased calcium is associated with the promoted VSMC phenotype switching in MFS. SERCA may become a novel therapeutic target for suppressing aneurysm progression in MFS.


Asunto(s)
Síndrome de Marfan , Músculo Liso Vascular , Ratones , Animales , Calcio , Síndrome de Marfan/genética , Síndrome de Marfan/complicaciones , Estudios Retrospectivos , Fenotipo , Miocitos del Músculo Liso
10.
Rev Cardiovasc Med ; 24(11): 338, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39076438

RESUMEN

Background: The visceral-adiposity-tissue index (VATI) and the triglyceride-glucose (TyG) index were found to be correlated with an increased risk of cardiovascular events. However, data concerning the association between the visceral adiposity/TyG indexes and the complication of new-onset postoperative atrial fibrillation (POAF), especially in patients who had just undergone off-pump coronary artery bypass grafting (OPCABG), are rare. We explored the predictive value of the computed-tomography-based VATI and the TyG index on new-onset POAF after OPCABG. Methods: This study used longitudinal data from the cohort of 542 participants who underwent OPCABG in Beijing Anzhen Hospital since June 2017. The predictive relevance of the VATI and TyG index were evaluated through Cox proportional hazards models and receiver operating characteristic (ROC) curves. The dose‒response relationship of the VATI and TyG index with new-onset POAF was analyzed by multiple-adjusted spline regression models, and sensitivity analysis was used to explore the stability of our findings. Results: The analysis found that the highest tertile of VATI [hazard ratio (HR) 2.58, 95% confidence interval (CI) 1.12-3.45; p = 0.01] and TyG index (HR 2.88, 95% CI 1.76-4.71; p = 0.01) were significantly associated with new-onset POAF compared to the lowest tertile after full adjustment for age, sex, body mass index, c-reactive protein levels, diabetes, emergency operation, New York Heart Association (NYHA) III-IV, and left atrial diameter. The area under the ROC curve (AUC) was 0.897 (p < 0.001) and 0.878 (p < 0.001) for the VATI and TyG index, respectively. In addition, the multiple-adjusted spline regression models showed a nonlinear relationship between new-onset POAF and VATI and TyG index (p for nonlinearity < 0.001). Sensitivity analyses confirmed that the results were similar for most tertiles. Conclusions: The VATI and TyG index were significantly associated with an increased risk for the development of new-onset POAF after OPCABG. Clinical Trial Registration: NCT03729531, https://beta.clinicaltrials.gov/study/NCT03729531.

11.
Langmuir ; 39(12): 4530-4536, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36919933

RESUMEN

Lossless and efficient robotic grasping is becoming increasingly important with the widespread application of intelligent robotics in warehouse transportation, human healthcare, and domestic services. However, current sensors for feedback of grasping behavior are greatly restricted by high manufacturing cost, large volume and mass, complex circuit, and signal crosstalk. To solve these problems, here, we prepare lightweight distance sensor-based reduced graphene oxide (rGO)/MXene-rGO coaxial microfibers with interface buffer to assist lossless grasping of a robotic manipulator. The as-fabricated distance microsensor exhibits a high sensitivity of 91.2 m-1 in the distance range of 50-300 µm, a fast response time of 116 ms, a high resolution of 5 µm, and good stability in 500 cycles. Furthermore, the high-performance and lightweight microsensor is installed on the robotic manipulator to reflect the grasp state by the displacement imposed on the sensor. By establishing the correlation between the microsensing signal and the grasp state, the safe, non-destructive, and effective grasp and release of the target can be achieved. The lightweight and high-powered distance sensor displays great application prospects in intelligent fetching, medical surgery, multi-spindle automatic machines, and cultural relics excavation.

12.
Europace ; 25(11)2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37939825

RESUMEN

AIMS: Dapagliflozin has been widely used for the treatment of type 2 diabetes mellitus (T2DM) and heart failure (HF). However, data concerning the association between dapagliflozin and the recurrence of atrial fibrillation (AF), especially in patients following Cox-Maze IV (CMIV), are rare. We aim to explore the effect of dapagliflozin on the recurrence of AF after CMIV with and without T2DM or HF. METHODS AND RESULTS: The study of dapagliflozin evaluation in AF patients followed by CMIV (DETAIL-CMIV) is a prospective, double-blind, randomized, placebo-controlled trial. A total of 240 AF patients who have received the CMIV procedure will be randomized into the dapagliflozin group (10 mg/day, n = 120) and the placebo group (10 mg/day, n = 120) and treated for 3 months. The primary endpoint is any documented atrial tachyarrhythmia (AF, atrial flutter or atrial tachycardia) lasting 30 s following a blanking period of 3 months after CMIV. CONCLUSION: DETAIL-CMIV will determine whether the sodium-glucose cotransporter-2 inhibitor dapagliflozin, added to guideline-recommended post-operative AF therapies, safely reduces the recurrence rate of AF in patients with and without T2DM or HF.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Diabetes Mellitus Tipo 2 , Insuficiencia Cardíaca , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/cirugía , Estudios Prospectivos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Ablación por Catéter/métodos , Insuficiencia Cardíaca/cirugía , Resultado del Tratamiento
13.
Environ Sci Technol ; 57(30): 10911-10918, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37440474

RESUMEN

Microplastics have been detected in human stool, lungs, and placentas, which have direct exposure to the external environment through various body cavities, including the oral/anal cavity and uterine/vaginal cavity. Crucial data on microplastic exposure in completely enclosed human organs are still lacking. Herein, we used a laser direct infrared chemical imaging system and scanning electron microscopy to investigate whether microplastics exist in the human heart and its surrounding tissues. Microplastic specimens were collected from 15 cardiac surgery patients, including 6 pericardia, 6 epicardial adipose tissues, 11 pericardial adipose tissues, 3 myocardia, 5 left atrial appendages, and 7 pairs of pre- and postoperative venous blood samples. Microplastics were not universally present in all tissue samples, but nine types were found across five types of tissue with the largest measuring 469 µm in diameter. Nine types of microplastics were also detected in pre- and postoperative blood samples with a maximum diameter of 184 µm, and the type and diameter distribution of microplastics in the blood showed alterations following the surgical procedure. Moreover, the presence of poly(methyl methacrylate) in the left atrial appendage, epicardial adipose tissue, and pericardial adipose tissue cannot be attributed to accidental exposure during surgery, providing direct evidence of microplastics in patients undergoing cardiac surgery. Further research is needed to examine the impact of surgery on microplastic introduction and the potential effects of microplastics in internal organs on human health.

14.
Nano Lett ; 22(21): 8574-8583, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36279311

RESUMEN

A highly stable interface for aqueous rechargeable Zn batteries is of importance to inhibit the growth of Zn dendrites and suppress the side reactions. In this work, we have developed a stable honeycomb-like ZnO passivation protective layer on the Zn surface, which is in situ generated with the assistance of a nonionic surfactant additive (polyethylene glycol tert-octylphenyl ether, denoted as PEGTE). The ZnO passivation layer can facilitate the uniform distribution of the electric field, guiding the uniform deposition of Zn2+ and inhibit the generation of dendrites. As a result, the symmetric cell using the electrolyte with PEGTE shows an excellent performance at high areal capacity, reflected by stable cycling for over 2400 h at 5 mAh/cm2 and 1300 h at 10 mAh/cm2. The full cell paired with V2O5 demonstrates a long lifespan for more than 600 cycles at a low negative/positive capacity ratio.

15.
Nano Lett ; 22(3): 1302-1310, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35089723

RESUMEN

For practical sodium-ion batteries, both high electrochemical performance and cost efficiency of the electrode materials are considered as two key parameters. Prussian blue analogues (PBAs) are broadly recognized as promising cathode materials due to their low cost, high theoretical capacity, and cycling stability, although they suffer from low-crystallinity-induced performance deterioration. Herein, a facile "ice-assisted" strategy is presented to prepare highly crystallized PBAs without any additives. By suppressing structure defects, the cathode exhibits a high capacity of 123 mAh g-1 with initial Coulombic efficiency of 87.2%, a long cycling lifespan of 3000 cycles, and significantly enhanced high/low temperature performance and calendar life. Remarkably, the low structure distortion and high sodium diffusion coefficient have been identified via in situ synchrotron powder diffraction and first-principles calculations, while its thermal stability has been analyzed by in situ heated X-ray powder diffraction. We believe the results could pave the way to the low-cost and large-scale application of PBAs in all-climate sodium-ion batteries.

16.
Small ; 18(43): e2106635, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35218294

RESUMEN

As one of the most competitive candidates for large-scale energy storage, zinc-air batteries (ZABs) have attracted great attention due to their high theoretical specific energy density, low toxicity, high abundance, and high safety. It is highly desirable but still remains a huge challenge, however, to achieve cheap and efficient electrocatalysts to promote their commercialization. Recently, Fe-based single-atom and dual-atom catalysts (SACs and DACs, respectively) have emerged as powerful candidates for ZABs derived from their maximum utilization of atoms, excellent catalytic performance, and low price. In this review, some fundamental concepts in the field of ZABs are presented and the recent progress on the reported Fe-based SACs and DACs is summarized, mainly focusing on the relationship between structure and performance at the atomic level, with the aim of providing helpful guidelines for future rational designs of efficient electrocatalysts with atomically dispersed active sites. Finally, the great advantages and future challenges in this field of ZABs are also discussed.

17.
Small ; 18(8): e2104296, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34873861

RESUMEN

The investigation of carbonaceous-based anode materials will promote the fast application of low-cost potassium-ion batteries (PIBs). Here a nitrogen and oxygen co-doped yolk-shell carbon sphere (NO-YS-CS) is constructed as anode material for K-ion storage. The novel architecture, featuring with developed porous structure and high surface specific area, is beneficial to achieving excellent electrochemical kinetics behavior and great electrode stability from buffering the large volume expansion. Furthermore, the N/O heteroatoms co-doping can not only boost the adsorption and intercalation ability of K-ion but also increase the electron transfer capability. It is also demonstrated by experimental results and DFT calculations that K-ion insertion/extraction proceeds through both intercalation and surface capacitive adsorption mechanisms. As expected, the NO-YS-CS electrodes show high initial charge capacity of 473.7 mAh g-1 at 20 mA g-1 , ultralong cycling life over 2500 cycles with the retention of 85.8% at 500 mA g-1 , and superior rate performance (183.3 mAh g-1 at 1.0 A g-1 ). The K-ion full cell, with a high energy density of 271.4 Wh kg-1 and an excellent cyclic stability over 500 cycles, is successfully fabricated with K2 Fe[Fe(CN)6 ] cathode. This work will provide new insight on the synthesis and mechanism understanding of high-performance hard carbon anode for PIBs.

18.
Nano Lett ; 21(24): 10453-10461, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34846156

RESUMEN

Lithium/sodium metal batteries have attracted enormous attention as promising candidates for high-energy storage devices. However, their practical applications are impeded by the growth of dendrites upon Li/Na plating. Here, we report that holey 2D N-doped TiNb2O7 (N-TNO) nanosheets with high electroactive surface area and large amounts of lithiophilic/sodiophilic sites can effectively regulate Li/Na deposition as an interfacial layer, leading to an excellent cycling stability. The N-TNO interfacial layer enables the Li||Li symmetric cell to sustain stable electrodeposition over 1000 h as well as the Na||Na cell to stably cycle for 2400 h at 1 mA cm-2 and 3 mA h cm-2 with a depth of discharge as high as 50%. The full cells of the Li/Na anodes based on the N-TNO layer paired with the LiFePO4 and NaTi2(PO4)3 cathodes, respectively, show a very stable cycling over 1000 cycles at a negative-to-positive electrode capacity (N/P) ratio up to 3.

19.
Nano Lett ; 21(19): 7970-7978, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34605652

RESUMEN

The performance of single-atom catalysts strongly depends on their particular coordination environments in the near-surface region. Herein, we discover that engineering extra Pt single atoms in the subsurface (Ptsubsurf) can significantly enhance the catalytic efficiency of surface Pt single atoms toward the oxygen reduction reaction (ORR). We experimentally and theoretically investigated the effects of the Ptsubsurf single atoms implanted in different positions of the subsurface of Co particles. The local environments and catalytic properties of surface Pt1 are highly tunable via Ptsubsurf doping. Specifically, the obtained Pt1@Co/NC catalyst displays a remarkable performance for ORR, achieving mass activity of 4.2 mA µgPt-1 (28 times higher than that of commercial Pt/C) at 0.9 V versus reversible hydrogen electrode (RHE) in 0.1 M HClO4 solution with high stability over 30000 cycles.

20.
Nano Lett ; 21(1): 619-627, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33300798

RESUMEN

Sodium (Na) metal is considered as a promising anode candidate for large-scale energy storage systems because of its high theoretical capacity and low electrochemical redox potential. However, Na anode suffers from a few challenges, such as the dendrite growth and severe parasitic reactions with electrolytes, which greatly hinder its practical applications. In this work, we demonstrate that an organosulfur compound additive (tetramethylthiuram disulfide) provides a facile and promising approach to overcome the above challenges in carbonate-based electrolytes. This unique organosulfur additive can in situ form a stable interfacial protection layer rich in organic sulfide salts on the sodium metal surface during cycling, leading to a stable stripping/plating cycling. Additionally, a cycling Coulombic efficiency of 94.25% is achieved, and the full battery using Prussian Blue as a cathode delivers a reversible capacity of 86.2 mAh g-1 with a capacity retention of 80% after 600 cycles at 4 C.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA