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1.
ACS Appl Mater Interfaces ; 16(10): 12599-12611, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38437708

RESUMEN

The rapid decline of the reversible capacity originating from microcracks and surface structural degradation during cycling is still a serious obstacle to the practical utilization of Ni-rich LiNixCoyAl1-x-yO2 (x ≥ 0.8) cathode materials. In this research, a feasible Hf-doping method is proposed to improve the electrochemical performance of LiNi0.9Co0.08Al0.02O2 (NCA90) through microstructural optimization and structural enhancement. The addition of Hf refines the primary particles of NCA90 and develops them into a short rod shape, making them densely arranged along the radial direction, which increases the secondary particle toughness and reduces their internal porosity. Moreover, Hf-doping stabilizes the layered structure and suppresses the side reactions through the introduction of robust Hf-O bonding. Multiple advantages of Hf-doping allowed significant improvement of the cycling stability of LiNi0.895Co0.08Al0.02Hf0.005O2 (NCA90-Hf0.5), with a reversible capacity retention rate of 95.3% after 100 cycles at 1 C, as compared with only 82.0% for the pristine NCA90. The proposed synergetic strategy combining microstructural engineering and crystal structure enhancement can effectively resolve the inherent capacity fading of Ni-rich layered cathodes, promoting their practical application for next-generation lithium-ion batteries.

2.
ACS Nano ; 18(10): 7666-7676, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38415604

RESUMEN

Constructing a robust solid electrolyte interphase (SEI) is extremely critical to developing high-energy-density silicon (Si)-based lithium-ion batteries. However, it is still elusive how to accurately manipulate the chemical composition and structure of the SEI layer. Herein, a LiF-dominated SEI film intertwined by a highly elastic polymer is achieved by regulating the defluorination mechanism of the fluorinated carbonate additive on the Si electrode surface. The experimental and computational results confirm that the decomposition route of trans-difluoroethylene carbonate (DFEC) molecules can be significantly altered in the presence of lithium difluoro(oxalato)borate (LiDFOB) additive. The induction of direct defluorination of DFEC step by LiDFOB, as opposed to the breaking of C-O bonds without LiDFOB addition, is crucial in ensuring the exclusive formation of LiF-dominated SEI and maintaining the cyclic structure of DFEC. The defluorinated DFEC easily polymerizes to form poly(vinylene carbonate), enhancing the elasticity of the SEI. The resulting LiF-dominated SEI film with a polymer interwoven outer layer shows enhanced ionic conductivity and mechanical stability, which can effectively accelerate electrode reaction kinetics and maintain the structural stability of the Si electrode. As a result, the Si electrode with the electrolyte containing the designed dual-additive exhibits superior cycling stability and excellent rate performance, delivering a high reversible capacity of 1487.3 mAh g-1 after 1000 cycles at 2 A g-1.

3.
ACS Nano ; 17(8): 7806-7812, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37023331

RESUMEN

An efficient surface modification strategy is proposed to significantly increase the initial Coulombic efficiency (ICE) of SiO anode material. The SiO@Fe material with the Fe nanocluster homogeneously decorating on the SiO surface is successfully prepared by a chemical vapor deposition process. The well-dispersed Fe nanoclusters realize an Ohmic contact with lithium silicates, the commonly regarded irreversible lithiation product, which effectively lowers the electron conduction barriers and promotes the concomitant lithium-ion release of the lithium silicates upon the delithiation process, increasing the ICE of the SiO anode. The prepared SiO@Fe exhibits a much higher ICE of 87.2% compared to 64.4% of pristine SiO, with the largest increment (23%) never reported, except for the prelithiation, and delivers significantly enhanced cycling and rate performance. These findings provide an effective way to convert the "inert" phase to "active" which essentially increases the ICE of the electrode.

4.
Small Methods ; 7(4): e2201138, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36843320

RESUMEN

Perovskites have shown tremendous promise as functional materials for several energy conversion and storage technologies, including rechargeable batteries, (electro)catalysts, fuel cells, and solar cells. Due to their excellent operational stability and performance, high-entropy perovskites (HEPs) have emerged as a new type of perovskite framework. Herein, this work reviews the recent progress in the development of HEPs, including synthesis methods and applications. Effective strategies for the design of HEPs through atomistic computations are also surveyed. Finally, an outlook of this field provides guidance for the development of new and improved HEPs.

5.
Materials (Basel) ; 15(24)2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36556543

RESUMEN

Cu-content La1-xSrxNi1-yCuyO3-δ perovskites with A-site strontium doping have been tuned as cobalt-free cathode materials for high-performance anode-supported SOFCs, working at an intermediate-temperature range. All obtained oxides belong to the R-3c trigonal system, and phase transitions from the R-3c space group to a Pm-3m simple perovskite have been observed by HT-XRD studies. The substitution of lanthanum with strontium lowers the phase transition temperature, while increasing the thermal expansion coefficient (TEC) and oxygen non-stoichiometry δ of the studied materials. The thermal expansion is anisotropic, and TEC values are similar to commonly used solid electrolytes (e.g., 14.1 × 10-6 K-1 for La0.95Sr0.05Ni0.5Cu0.5O3-δ). The oxygen content of investigated compounds has been determined as a function of temperature. All studied materials are chemically compatible with GDC-10 but react with LSGM and 8YSZ electrolytes. The anode-supported SOFC with a La0.95Sr0.05Ni0.5Cu0.5O3-δ cathode presents an excellent power density of 445 mW·cm-2 at 650 °C in humidified H2. The results indicate that La1-xSrxNi1-yCuyO3-δ perovskites with strontium doping at the A-site can be qualified as promising cathode candidates for anode-supported SOFCs, yielding promising electrochemical performance in the intermediate-temperature range.

6.
Membranes (Basel) ; 12(10)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36295767

RESUMEN

In this work, magnesium-doped Sr2Fe1.2Mg0.2Mo0.6O6-δ and Sr2Fe0.9Mg0.4Mo0.7O6-δ double perovskites with excellent redox stability have been successfully obtained. The physicochemical properties including: crystal structure properties, redox stability, thermal expansion properties in oxidizing and reducing conditions, oxygen content as a function of temperature and transport properties, as well as the chemical compatibility with typical electrolytes have been systematically investigated. The in situ oxidation of reduced samples using high-temperature XRD studies shows the crystal structure of materials stable at up to a high-temperature range. The in situ reduction and oxidation of sinters with dilatometer measurements prove the excellent redox stability of materials, with the thermal expansion coefficients measured comparable with electrolytes. The oxygen nonstoichiometry δ of compounds was determined and recorded in air and argon up to 900 °C. Sr2Fe1.2Mg0.2Mo0.6O6-δ oxide presents satisfactory values of electrical conductivity in air (56.2 S·cm-1 at 600 °C) and reducing conditions (10.3 S·cm-1 at 800 °C), relatively high coefficients D and k, and good ionic conductivity (cal. 0.005 S·cm-1 at 800 °C). The stability studies show that both compounds are compatible with Ce0.8Gd0.2O1.9 but react with the La0.8Sr0.2Ga0.8Mg0.2O3-d electrolyte. Therefore, the magnesium-doped double perovskites with excellent redox stability can be potentially qualified as electrode materials for symmetrical SOFCs and are of great interest for further investigations.

7.
Asia Pac J Clin Nutr ; 31(3): 371-377, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36173209

RESUMEN

BACKGROUND AND OBJECTIVES: The dietary glycemic index (GI) and glycemic load (GL) have garnered scholarly attention for their roles in weight management and glycemic control. Flaxseed is a good source of fiber, lignans, and omega-3 fatty acids. This study evaluated healthy individuals' acute glycemic response and satiety following the consumption of flaxseed-enriched snack bars. METHODS AND STUDY DESIGN: Nineteen healthy men and women consumed flaxseed bars or a glucose solution containing 50 g of available carbohydrates. Capillary blood glucose concentrations were obtained through the finger-prick test. The GI and GL values of the flaxseed bars were calculated using incremental area under the glucose response curve. Over 2 h, subjective satiety was examined at 0 (fasting), 15, 30, 45, 60, 90 and 120min following the consumption of flaxseed bars or saltine crackers containing 300 kcal by using a visual analogue scale (VAS). RESULTS: Compared with that of the glucose solution, the glucose concentrations of the flaxseed bars (15-90 min) were significantly lower (p<0.001). The GI and GL values of the flaxseed bars were 30.0±23.0 and 2.3±0.2, respectively. Compared with saltine cracker consumption, flaxseed bars consumption resulted in lower hunger and higher satiety. The satiety index score of the flaxseed bars was 1.6 times higher than that of the saltine crackers. CONCLUSIONS: Although further studies are warranted to evaluate the long-term effects of flaxseed-enriched snacks on glycemia and energy balance, our findings suggest that the incorporation of flaxseed into snack bars is a viable strategy for the management of obesity and diabetes.


Asunto(s)
Ácidos Grasos Omega-3 , Lino , Lignanos , Glucemia , Estudios Cruzados , Ácidos Grasos Omega-3/farmacología , Femenino , Lino/metabolismo , Glucosa , Índice Glucémico/fisiología , Humanos , Lignanos/farmacología , Masculino , Bocadillos
8.
Nanoscale ; 13(48): 20481-20487, 2021 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-34853845

RESUMEN

Despite the advantage of high capacity, practical implementation of the tin disulfide (SnS2) anode for lithium-ion batteries is still plagued by the inferior rate performance due to its low intrinsic electronic conductivity and mediocre ion transport in the bulk. Herein, to address these issues, a peculiar heterojunction of SnS2-SnS quantum dots (QDs) closely coupled with reduced graphene oxide (rGO) sheets was developed. Because of the typical n-type and p-type semiconductor characteristics of SnS2 and SnS, respectively, the formed pn junction at the SnS2/SnS interface will induce a built-in electric field, which can significantly accelerate lithium-ion transport through the SnS2/SnS interface. The ultrafine SnS2 and SnS nano-domains with superlong pn junction interfacial length construct an accelerated lithium-ion diffusion network, while the conductive rGO nanosheets provide a high-speed electron conduction pathway. Meanwhile, the flexible rGO chemically coupled with SnS2/SnS buffers the volumetric variation during repeated lithiation/delithiation processes and guarantees robust structural durability. These merits afford the designed SnS2-SnS/rGO electrode with fast electrode reaction kinetics and good structural durability upon cycling. Consequently, the delicate SnS2-SnS/rGO electrode harvests a superlative rate capability of 926 and 865 mA h g-1 at 5 and 10 A g-1, respectively, and excellent long-term cycling stability with a high reversible capacity of 1075 mA h g-1 at 1 A g-1 up to 1000 cycles with negligible degradation.

9.
ACS Appl Mater Interfaces ; 13(41): 48569-48581, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34636230

RESUMEN

Porphyrins and their derivatives are a unique class of multifunctional and modifiable π-conjugated heterocyclic organic molecules, which have been widely applied in the fields of optoelectronic devices and catalysis. However, the application of porphyrins in polymer electrolytes for all-solid-state lithium-ion batteries (ASSLIBs) has rarely been reported. Herein, porphyrin molecules modified by polyether chains are used for composite solid-state polymer electrolytes (CSPEs) for the first time. The introduction of a modified porphyrin in an electrolyte can not only promote the electrochemical properties by constructing ordered ion channels via the intermolecular interaction between π-conjugated heterocyclic porphyrins, but also significantly improve the mechanical strength and interface contact between the electrolyte membrane and the lithium metal anode. Consequently, the all-solid-state batteries assembled by the modified porphyrin composite polymer electrolyte, LiFePO4 cathodes, and Li anodes deliver a higher discharge capacity of 158.2 mA h g-1 at 60 °C, 0.2 C, which remains at 153.6 mA h g-1 after 120 cycles with an average coulombic efficiency of ∼99.60%. Furthermore, the flexible porphyrin-based composite polymer electrolyte can also enable a Li || LiCoO2 battery to exhibit a maximum discharge capacity of 108.6 mA h g-1 at 60 °C, 0.1 C with an active material loading of 2-3 mg cm-2, which is unable to realize for the corresponding batteries with a pure PEO-based polymer electrolyte. This work not only broadens the application scope of porphyrins, but also proposes a novel method to fabricate CSPEs with improved electrochemical and mechanical properties, which may shed new light on the development of CSPEs for next-generation high-energy-density lithium-ion batteries.

10.
ACS Appl Mater Interfaces ; 13(7): 8445-8454, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33560822

RESUMEN

Polyanion-type Na3V2(PO4)3 (NVP) is an overwhelmingly attractive cathode material for sodium-ion batteries (SIBs) because of its high structural stability and fast Na+ mobility. However, its practical application is strongly plagued by either nanoscale particle size or poor rate performance. Herein, a micro/nanocomposite NVP cathode with a hierarchical porous structure is proposed to solve the problem. The microscale NVP material assembled by interconnected nanoflakes with N-doped carbon coating that is capable of simultaneously providing fast carrier transmission dynamics and outstanding structural integrity exhibits precedent sodium-storage behavior. It delivers a superior rate capability (79.1 mAh g-1 at 200C) and excellent long-life cycling (capacity retention of 73.4% after 10 000 cycles at 100C). Remarkably, a pouch-type sodium-ion full cell consisting of the as-obtained NVP cathode and a hard carbon anode demonstrates the gravimetric energy density as high as 212 Wh kg-1 and an exceptional rate performance (71.8 mAh g-1 at 10C). Such structural design of fabricating micro/nanocomposite electrode materials is expected to accelerate the practical applications of SIBs for large-scale energy storage.

11.
ACS Appl Mater Interfaces ; 13(2): 3287-3294, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33400481

RESUMEN

Exsolution of catalytic nanoparticles (NPs) from perovskites has arisen as a flexible method to develop high-performance functional materials with enhanced durability for energy conversion and catalytic synthesis applications. Here, we unravel the interface structure of the in situ exsolved alloy nanoparticles from the double perovskite substrate on the atomic scale. The results show that the Co-Fe alloy NPs exsolved topologically from the {100} facets terminations of the Sr2FeMo0.65Co0.35O6-δ (SFMC) double perovskite along ⟨100⟩ directions exhibiting the same orientation and identical crystal structure. The lattice planes of these two phases align and insert into each other at the interface, forming a smooth and continuous coherent connection. The presence of moiré patterns at the interface confirms the topological exsolution mechanism. The coherent interface can significantly reduce the interfacial energy and therefore stabilize the exsolved nanoparticles. Therefore, excellent and stable electrochemical performance of the NP-decorated SFMC perovskite is observed as the anode for solid oxide fuel cells. Our contribution promotes a fundamental understanding of the interface structure of the in situ exsolved alloy nanoparticles from perovskite substrate.

12.
ACS Appl Mater Interfaces ; 10(42): 35963-35971, 2018 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-30251835

RESUMEN

Na3V2(PO4)3 has shown great promise in next-generation cathode materials for sodium-ion batteries owning to its fast Na+ diffusion in the three-dimensional open NASICON framework and high theoretical energy density. However, Na3V2(PO4)3 suffers from undesirable rate performance and unstable cyclability arising from low electronic conductivity. Herein, we propose a facile approach for significantly enhancing the electrochemical properties of Na3V2(PO4)3 by Ti doping at V site and constructing nanoparticle@carbon core-shell nanostructure. This material design provides fast electron conduction network within the whole active particles because of the mixed valence Ti4+/3+ in bulk and highly conductive carbon shell on the surface. Lattice doping and carbon coating reduce the electrode polarization and facilitate the electrode reaction kinetics, while the nanostructure enhances the ionic conduction by shortening the diffusion distance and offers sufficient contact of active particles with organic electrolyte. The multiple synergetic effects enable a superior electrochemical performance. The optimized Na3V1.9Ti0.1(PO4)3@C cathode shows a high specific capacity (116.6 mAh g-1 at 1C), an unprecedented rate performance (93.4 mAh g-1 at 400C), and an exceptional long-term high-rate cycling stability (capacity retention of 69.5% after 14 000 cycles at 100C, corresponding to 0.0002% decay per cycle).

13.
Phys Chem Chem Phys ; 20(33): 21685-21692, 2018 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-30101266

RESUMEN

The effects of A-site substitutions on the interstitial oxygen formation energy and the migration energy in layered A2-xA'xNiO4+δ (A = selected lanthanides, A' = Ba, Sr, Ca) are investigated by first principles calculations. The interstitial oxygen formation energy is negative, in the range of -4.81 eV to -3.45 eV, strongly supporting easiness of formation of the interstitial oxygen defects in the (A,A')O rock salt plane. The Pr2NiO4+δ compound shows the lowest formation energy, indicating the highest amount of interstitial oxygen. Doping with alkaline earth cations (A') increases the formation energy of the interstitial oxygen, which prefers to be located far away from the dopants. Nevertheless, Ca seems to be the best choice, due to relatively low formation energy. Calculations for the four kinds of diffusion paths allow it to be predicted that the oxygen transport in A2-xA'xNiO4+δ is governed by the interstitialcy mechanism in the ab plane, because of the significantly lower energy barriers for this mechanism. An interesting finding is achieved for A2NiO4+δ (A = Pr, Nd, Sm), for which the energy barriers for the interstitialcy transport are negative (-0.47 eV, -0.33 eV and -0.02 eV, respectively), implying that the transition state is more stable than the assumed initial state. A new structural configuration is proposed in this work, with the adjacent apical oxygen located at the adjacent interstitial site, which shows ca. 0.5 eV lower free energy than that of the initial model. This result provides a new understanding for the location of the interstitial and the adjacent apical oxygens from an energetic point of view and supports previously published experimental data. It is found that alkaline earth doping at the A-site deteriorates the interstitial oxygen diffusion in La2-xA'xNiO4.25 materials, but concerning overall transport properties, Ca seems to be a good dopant from an energetic point of view, when compared with Ba and Sr.

14.
ACS Appl Mater Interfaces ; 10(34): 28533-28540, 2018 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-30074762

RESUMEN

Two-dimensional (2D) tin disulfide (SnS2) has attracted intensive research owing to its high specific capacity for Li and Na storage, natural abundance, as well as environmental friendliness. However, the poor reaction kinetics, low intrinsic electrical conductivity, and severe volumetric variation upon cycling processes of SnS2 impede its widespread application. In this work, SnS2 nanosheets with active-site-enriched surface intimately grown on reduced graphene oxide (rGO) via C-O-Sn chemical bonds are prepared. The aligning affords more active sites for electrode reaction and short transport pathways for Li+/Na+ and electrons. The strong chemical bonding enhances the interfacial affinity of SnS2 with rGO and inhibits the detachment of active SnS2 from rGO during repeated charge and discharge processes, which can ensure an integrated electrode structure. The 3D conductive and flexible rGO network improves the conductivity of the entire composite and buffers the volume change of SnS2 upon charge/discharge. These advantages enable the designed SnS2/rGO nanocomposite to have high specific capacity, superior rate capability, and outstanding long-cycling stability for both Li and Na storage.

15.
ACS Appl Mater Interfaces ; 9(41): 35880-35887, 2017 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-28948774

RESUMEN

Tin disulfide is considered to be a promising anode material for Li ion batteries because of its high theoretical capacity as well as its natural abundance of sulfur and tin. Practical implementation of tin disulfide is, however, strongly hindered by inferior rate performance and poor cycling stability of unoptimized material. In this work, carbon-encapsulated tin disulfide nanoplates with a (101) plane orientation are prepared via a facile hydrothermal method, using polyethylene glycol as a surfactant to guide the crystal growth orientation, followed by a low-temperature carbon-coating process. Fast lithium ion diffusion channels are abundant and well-exposed on the surface of such obtained tin disulfide nanoplates, while the designed microstructure allows the effective decrease of the Li ion diffusion length in the electrode material. In addition, the outer carbon layer enhances the microscopic electrical conductivity and buffers the volumetric changes of the active particles during cycling. The optimized, carbon coated tin disulfide (101) nanoplates deliver a very high reversible capacity (960 mAh g-1 at a current density of 0.1 A g-1), superior rate capability (796 mAh g-1 at a current density as high as 2 A g-1), and an excellent cycling stability of 0.5 A g-1 for 300 cycles, with only 0.05% capacity decay per cycle.

16.
ACS Nano ; 10(9): 8526-35, 2016 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-27556425

RESUMEN

A designed nanostructure with MoS2 nanosheets (NSs) perpendicularly grown on graphene sheets (MoS2/G) is achieved by a facile and scalable hydrothermal method, which involves adsorption of Mo7O24(6-) on a graphene oxide (GO) surface, due to the electrostatic attraction, followed by in situ growth of MoS2. These results give an explicit proof that the presence of oxygen-containing groups and pH of the solution are crucial factors enabling formation of a lamellar structure with MoS2 NSs uniformly decorated on graphene sheets. The direct coupling of edge Mo of MoS2 with the oxygen from functional groups on GO (C-O-Mo bond) is proposed. The interfacial interaction of the C-O-Mo bonds can enhance electron transport rate and structural stability of the MoS2/G electrode, which is beneficial for the improvement of rate performance and long cycle life. The graphene sheets improve the electrical conductivity of the composite and, at the same time, act not only as a substrate to disperse active MoS2 NSs homogeneously but also as a buffer to accommodate the volume changes during cycling. As an anode material for lithium-ion batteries, the manufactured MoS2/G electrode manifests a stable cycling performance (1077 mAh g(-1) at 100 mA g(-1) after 150 cycles), excellent rate capability, and a long cycle life (907 mAh g(-1) at 1000 mA g(-1) after 400 cycles).

17.
ACS Nano ; 10(9): 8660-9, 2016 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-27529355

RESUMEN

A metallic nanoparticle-decorated ceramic anode was prepared by in situ reduction of the perovskite Sr2FeMo0.65Ni0.35O6-δ (SFMNi) in H2 at 850 °C. The reduction converts the pure perovksite phase into mixed phases containing the Ruddlesden-Popper structure Sr3FeMoO7-δ, perovskite Sr(FeMo)O3-δ, and the FeNi3 bimetallic alloy nanoparticle catalyst. The electrochemical performance of the SFMNi ceramic anode is greatly enhanced by the in situ exsolved Fe-Ni alloy nanoparticle catalysts that are homogeneously distributed on the ceramic backbone surface. The maximum power densities of the La0.8Sr0.2Ga0.8Mg0.2O3-δ electrolyte supported a single cell with SFMNi as the anode reached 590, 793, and 960 mW cm(-2) in wet H2 at 750, 800, and 850 °C, respectively. The Sr2FeMo0.65Ni0.35O6-δ anode also shows excellent structural stability and good coking resistance in wet CH4. The prepared SFMNi material is a promising high-performance anode for solid oxide fuel cells.

19.
ACS Appl Mater Interfaces ; 7(3): 1693-8, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-25561398

RESUMEN

Si-based electrodes for lithium ion batteries typically exhibit high specific capacity but poor cycling performance. A possible strategy to improve the cycling performance is to design a novel electrode nanostructure. Here we report the design and fabrication of Ni/Si-nanoparticles/graphite clothing hybrid electrodes with a sandwich structure. An efficient dip-coating of Si-NPs combined with carbon deposition was adopted to synthesize the unique architecture, where the Si-NPs are sandwiched between the Ni matrix and the graphite clothing. This material architecture offers many critical features that are desirable for high-performance Si-based electrodes, including efficient ion diffusion, high conductivity, and structure durability, thus ensuring the electrode with outstanding electrochemical performance (reversible capacity of 1800 mA h g(-1) at 2 A g(-1) after 500 cycles). In addition, the hybrid anode does not require any polymeric binder and conductive additives and holds great potential for application in Li-ion batteries.

20.
BMJ Qual Saf ; 23(10): 847-56, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24736029

RESUMEN

BACKGROUND: Existing patient safety climate instruments, most of which have been developed in the USA, may not accurately reflect the conditions in the healthcare systems of other countries. OBJECTIVES: To develop and evaluate a patient safety climate instrument for healthcare workers in Chinese hospitals. METHODS: Based on a review of existing instruments, expert panel review, focus groups and cognitive interviews, we developed items relevant to patient safety climate in Chinese hospitals. The draft instrument was distributed to 1700 hospital workers from 54 units in six hospitals in five Chinese cities between July and October 2011, and 1464 completed surveys were received. We performed exploratory and confirmatory factor analyses and estimated internal consistency reliability, within-unit agreement, between-unit variation, unit-mean reliability, correlation between multi-item composites, and association between the composites and two single items of perceived safety. RESULTS: The final instrument included 34 items organised into nine composites: institutional commitment to safety, unit management support for safety, organisational learning, safety system, adequacy of safety arrangements, error reporting, communication and peer support, teamwork and staffing. All composites had acceptable unit-mean reliabilities (≥0.74) and within-unit agreement (Rwg ≥0.71), and exhibited significant between-unit variation with intraclass correlation coefficients ranging from 9% to 21%. Internal consistency reliabilities ranged from 0.59 to 0.88 and were ≥0.70 for eight of the nine composites. Correlations between composites ranged from 0.27 to 0.73. All composites were positively and significantly associated with the two perceived safety items. CONCLUSIONS: The Chinese Hospital Survey on Patient Safety Climate demonstrates adequate dimensionality, reliability and validity. The integration of qualitative and quantitative methods is essential to produce an instrument that is culturally appropriate for Chinese hospitals.


Asunto(s)
Liderazgo , Cultura Organizacional , Seguridad del Paciente , Garantía de la Calidad de Atención de Salud , Administración de la Seguridad , Adolescente , Adulto , China , Femenino , Grupos Focales , Investigación sobre Servicios de Salud , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Modelos Organizacionales , Psicometría , Encuestas y Cuestionarios
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