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1.
Small ; 14(13): e1703969, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29363874

RESUMEN

The designable structure with 3D structure, ultrathin 2D nanosheets, and heteroatom doping are considered as highly promising routes to improve the electrochemical performance of carbon materials as anodes for lithium-ion batteries. However, it remains a significant challenge to efficiently integrate 3D interconnected porous frameworks with 2D tunable heteroatom-doped ultrathin carbon layers to further boost the performance. Herein, a novel nanostructure consisting of a uniform ultrathin N-doped carbon layer in situ coated on a 3D graphene framework (NC@GF) through solvothermal self-assembly/polymerization and pyrolysis is reported. The NC@GF with the nanosheets thickness of 4.0 nm and N content of 4.13 at% exhibits an ultrahigh reversible capacity of 2018 mA h g-1 at 0.5 A g-1 and an ultrafast charge-discharge feature with a remarkable capacity of 340 mA h g-1 at an ultrahigh current density of 40 A g-1 and a superlong cycle life with a capacity retention of 93% after 10 000 cycles at 40 A g-1 . More importantly, when coupled with LiFePO4 cathode, the fabricated lithium-ion full cells also exhibit high capacity and excellent rate and cycling performances, highlighting the practicability of this NC@GF.

2.
Phys Chem Chem Phys ; 18(46): 31361-31377, 2016 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-27845454

RESUMEN

The increasing demand for energy and growing concerns for environmental issues are promoting the development of organic electrode materials. Among these, conjugated carbonyl compounds (CCCs) represent one of the most attractive and promising candidates for sustainable and eco-benign energy storage devices in the coming future. However, most of the current compounds suffer from dissolution in organic electrolytes and low electronic conductivity, which result in severe capacity decay and poor rate performance. Recently, researchers have achieved considerable progress by introducing electroactive carbonyl compounds into carbon nanomaterials. This perspective provides an overview of the up-to-date development of these nanocomposites in metal ion batteries (lithium-ion batteries or sodium-ion batteries) and supercapacitors (SCs), including the synthesis, performance improvement and applications. We mainly focus on carbon nanotubes (CNTs), graphene and mesoporous carbon (MC) as carbon nanomaterials because of their high specific surface area, good conductivity, electrochemical stability and favourable interaction with conjugated carbonyl compounds. This strategy opens up new possibilities to realize cost-effective, sustainable and versatile energy storage devices.

3.
Autoimmun Rev ; 23(10): 103614, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39222675

RESUMEN

OBJECTIVES: We performed a systematic review and meta-analysis to assess whether patients with connective tissue disease (CTD)-associated interstitial lung diseases (ILD) have an increased prevalence of cardiovascular (CV) disease and to validate associated risk factors. METHODS: The PRISMA guidelines and PICO model were followed. We searched PubMed, Embase, Cochrane Library databases, Scopus, and Directory of Open Access Journals from inception to April 2024. RESULTS: Thirteen studies comprising of 12,520 patients were included. Patients with CTD-ILD had a significantly increased risk of CV disease than patients with CTD (relative risk [RR] = 1.65, 95 % confidence interval [CI]: 1.41, 1.93), which are related to the proportion of men (P = 0.001) and the proportion of smokers (P = 0.045). Subgroup analysis found that patients with CTD-ILD had a higher risk of heart failure (RR = 2.84, 95 % CI: 1.50, 5.39), arrhythmia (RR = 1.55, 95 % CI: 1.22, 1.97) than patients with CTD. Another subgroup analysis showed that RA-ILD and SSc-ILD were associated with an increased risk of CV disease, but not IIM-ILD and MCTD-ILD (RA-ILD: RR = 2.19, 95 % CI: 1.27, 3.80; SSc-ILD: RR = 1.53, 95 % CI: 1.29, 1.82). Besides, patients with CTD-ILD had a higher prevalence of pulmonary arterial hypertension (RR = 2.48, 95 % CI: 1.69, 3.63) than patients with CTD. CONCLUSIONS: Patients with CTD-ILD had a 1.65 times increased risk of CV than patients with CTD-non-ILD, with increased prevalence of heart failure and arrhythmia. The risk of CV disease in SSc-ILD and RA-ILD is increased and we should pay more attention to male smokers. In addition, compared with CTD patients, CTD-ILD patients had a higher risk of pulmonary arterial hypertension.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedades del Tejido Conjuntivo , Enfermedades Pulmonares Intersticiales , Estudios Observacionales como Asunto , Humanos , Enfermedades Pulmonares Intersticiales/epidemiología , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades Pulmonares Intersticiales/complicaciones , Enfermedades del Tejido Conjuntivo/complicaciones , Enfermedades del Tejido Conjuntivo/epidemiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Factores de Riesgo , Prevalencia
4.
Adv Mater ; 29(40)2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28856731

RESUMEN

Lithium-sulfur batteries, as one of the most promising next-generation batteries, attract tremendous attentions due to their high energy density and low cost. However, their practical application is hindered by their short cycling life and low volumetric capacity. Herein, compact, flexible, and free-standing films with a sandwich structure are designed simply by vacuum filtration, in which nanosulfur is homogenously coated by graphene and poly(3,4-ethylene-dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). This unique hierarchical structure not only provides a highly conductive network and intimate contacts between nanosulfur and graphene/PEDOT:PSS for effective charge transportation, but also offers synergistic physical restriction and chemical confinement of dissoluble intermediate lithium polysulfides during electrochemical processes. Therefore, these conductive compact films, used directly as cathodes, show the highest reversible volumetric capacity of 1432 Ah L-1 at 0.1 C and 1038 Ah L-1 at 1 C, and excellent cycling stability with a minimal decay rate of 0.04% per cycle over 500 cycles at 1 C. Meanwhile, remarkable rate performance with a high capacity of 701 mAh g-1 at 4 C is also achieved. Soft-packaged batteries based on this flexible cathode are further fabricated and demonstrate excellent mechanical and electrochemical properties with little capacity decay under folded state, highlighting the practical application of our deliberately designed electrode in a flexible power system.

5.
ChemSusChem ; 10(17): 3419-3426, 2017 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-28722277

RESUMEN

Small conjugated carbonyl compounds are intriguing candidates for organic electrode materials because of their abundance, high theoretical capacity, and adjustable molecular structure. However, their dissolution in aprotic electrolytes and poor conductivity eclipse them in terms of practical capacity, cycle life, and rate capability. Herein, we report a foldable and binder-free nanocomposite electrode consisting of 2-aminoanthraquinone (AAQ) nanowires wrapped within the 3 D graphene framework, which is prepared through antisolvent crystallization followed by a facile chemical reduction and selfassembly process. The nanocomposite exhibited a very high capacity of 265 mA h g-1 at 0.1 C for AAQ, realizing 100 % utilization of active material. Furthermore, the nanocomposite shows superior cycling stability (82 % capacity retention after 200 cycles at 0.2 C and 76 % capacity retention after 1000 cycles at 0.4 C) and excellent rate performance (153 mA h g-1 at 5 C). Particularly, the nanocomposite can deliver the highest capacity of 165 mA h g-1 among all reported anthraquinone- and anthraquinone-analogues-based electrodes per mass of the whole electrode, which is essential for practical application. Such outstanding electrochemical performance could be largely attributed to the wrapping structure of the flexible composite, which provides both conductivity and structural integrity.


Asunto(s)
Antraquinonas/química , Suministros de Energía Eléctrica , Grafito/química , Litio/química , Nanotecnología/métodos , Nanocables/química , Electrodos , Modelos Moleculares , Conformación Molecular
6.
ACS Appl Mater Interfaces ; 9(18): 15549-15556, 2017 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-28425698

RESUMEN

Polymer cathode materials are promising alternatives to inorganic counterparts for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) due to their high theoretical capacity, adjustable molecular structure, and strong adaptability to different counterions in batteries, etc. However, they suffer from poor practical capacity and low rate capability because of their intrinsically poor conductivity. Herein, we report the synthesis of self-assembled graphene/poly(anthraquinonyl sufide) (PAQS) composite aerogel (GPA) with efficient integration of a three-dimensional (3D) graphene framework with electroactive PAQS particles via a novel dispersion-assembly strategy which can be used as a free-standing flexible cathode upon mechanical pressing. The entire GPA cathode can deliver the highest capacity of 156 mAh g-1 at 0.1 C (1 C = 225 mAh g-1) with an ultrahigh utilization (94.9%) of PAQS and exhibits an excellent rate performance with 102 mAh g-1 at 20 C in LIBs. Furthermore, the flexible GPA film was also tested as cathode for SIBs and demonstrated a high-rate capability with 72 mAh g-1 at 5 C and an ultralong cycling stability (71.4% capacity retention after 1000 cycles at 0.5 C) which has rarely been achieved before. Such excellent electrochemical performance of GPA as cathode for both LIBs and SIBs could be ascribed to the fast redox kinetics and electron transportation within GPA, resulting from the interconnected conductive framework of graphene and the intimate interaction between graphene and PAQS through an efficient wrapping structure. This approach opens a universal way to develop cathode materials for powerful batteries with different metal-based counter electrodes.

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