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1.
Front Public Health ; 12: 1271409, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716248

RESUMO

Compensatory Health Beliefs (CHBs), the notion that healthy behaviors can offset the negative effects of unhealthy actions, have been widely explored in Western contexts. Yet, their relevance within the Chinese cultural milieu remains underexplored. The primary objective of this research was to develop and validate a Chinese version of the CHBs scale (CHBs-C), addressing the gap in the literature regarding the applicability of CHBs within the Chinese cultural context. A multi-stage translation (from English to Chinese) was first completed, and exploratory factor analysis was conducted (n = 476), yielding the 14-item scale (CHBs-C scale). Confirmatory factor analysis was conducted to assess the validity, and the 2-week test-retest reliability, internal consistency and convergent validity of the scale were also assessed (n = 308). Predict validity was verified through testing the relationships between CHBs and health behaviors and habits (n = 274). Factor analysis showed a different factor structure in Chinese context, with only one factor identical to the original version. The fitness index of the new factor structure was good. However, while the scale exhibited acceptable internal consistency and high test-retest reliability, its convergent validity and predictive validity was found to be limited on a general level. Despite this, significant correlations at the subscale level were identified, highlighting nuanced interactions between CHBs and specific health behaviors within the Chinese population. This study not only establishes the CHBs-C scale as a valid and reliable instrument for assessing compensatory health beliefs in China but also lays the groundwork for further exploration of its applications and the potential cultural adaptability of CHBs.


Assuntos
Comportamentos Relacionados com a Saúde , Psicometria , Humanos , Feminino , Masculino , Reprodutibilidade dos Testes , Adulto , Inquéritos e Questionários/normas , China , Análise Fatorial , Pessoa de Meia-Idade , Conhecimentos, Atitudes e Prática em Saúde , Adulto Jovem , Adolescente , Traduções
2.
Chem Commun (Camb) ; 59(77): 11536-11539, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37674372

RESUMO

Aqueous zinc-halogen batteries suffer from poor coulombic efficiency and short cycle life owing to the formation and dissolution of polyhalides in electrolytes. Herein, we apply a zinc-dual-halide complex strategy to confine free halides and suppress polyhalide formation. The high stabilities of zinc-dual-halide complexes are identified to be essential for effective confinement. The resulting Zn-Br2 and Zn-I2 cells deliver excellent rate capability and cycling stability, as well as high coulombic efficiency and energy efficiency.

3.
Chem Commun (Camb) ; 58(39): 5905-5908, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35474475

RESUMO

The transformation of polyanion cathodes into oxides in aqueous Zn batteries results in voltage decay. Herein, we uncover a polyanion dissolution and oxide re-electrodeposition process for this transformation. Accordingly, the dissolution is inhibited by reducing the water activity in the electrolyte with the hydrogen bond regulator of glucose (Glu). In the 4 m Zn(OTf)2/5.5 m Glu electrolyte, the VOPO4·2H2O cathode maintains the redox reactions at a high voltage of 1.6 V/1.5 V with stable capacity retention during cycling at different rates. It also shows promising electrochemical activity and stability at temperatures down to -20 °C.


Assuntos
Fontes de Energia Elétrica , Zinco , Eletrólitos , Ligação de Hidrogênio , Óxidos , Água
4.
Chem Commun (Camb) ; 58(31): 4845-4848, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35344986

RESUMO

The Mn2+ dissolution of MnO2 cathode materials causes rapid capacity decay in aqueous zinc batteries. We herein show that the dissolved Mn2+ can be deposited back to the cathode with the aid of a suitable conductive agent. The active material is thus retained for energy storage, and this MnO2/Mn2+ redox process also provides capacity. In the Mn2+ free ZnSO4 electrolyte, MnO2 delivers 325 mA h g-1 capacity at 0.1 A g-1, and 90.4% capacity retention is achieved after 3000 cycles at 5 A g-1. Our work demonstrates an effective strategy to realize stable cycling of MnO2 cathodes in aqueous zinc batteries without Mn2+ additives.

5.
ACS Appl Mater Interfaces ; 14(8): 10526-10534, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35175021

RESUMO

Aqueous rechargeable Zn-manganese dioxide (Zn-MnO2) hybrid batteries based on dissolution-deposition mechanisms exhibit ultrahigh capacities and energy densities due to the two-electron transformation between MnO2/Mn2+. However, the reported Zn-MnO2 hybrid batteries usually use strongly acidic and/or alkaline electrolytes, which may lead to environmental hazards and corrosion issues of the Zn anodes. Herein, we propose a new Zn-MnO2 hybrid battery by adding Al3+ into the sulfate-based electrolyte. The hybrid battery undergoes reversible MnO2/Mn2+ transformation and exhibits good electrochemical performances, such as a high discharge capacity of 564.7 mAh g-1 with a discharge plateau of 1.65 V, an energy density of 520.8 Wh kg-1, and good cycle life without capacity decay upon 2000 cycles. Experimental results and theoretical calculation suggest that the aquo Al3+ with Brønsted weak acid nature can act as the proton-donor reservoir to maintain the electrolyte acidity near the electrode surface and prevent the formation of Zn4(OH)6(SO4)·0.5H2O during discharging. In addition, Al3+ doping during charging introduces oxygen vacancies in the oxide structure and weakens the Mn-O bond, which facilitates the dissolution reaction during discharge. The mechanistic investigation discloses the important role of Al3+ in the electrolyte, providing a new fundamental understanding of the promising aqueous Zn-MnO2 batteries.

6.
Nat Commun ; 12(1): 4424, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285215

RESUMO

Rechargeable aqueous zinc-organic batteries are promising energy storage systems with low-cost aqueous electrolyte and zinc metal anode. The electrochemical properties can be systematically adjusted with molecular design on organic cathode materials. Herein, we use a symmetric small molecule quinone cathode, tetraamino-p-benzoquinone (TABQ), with desirable functional groups to protonate and accomplish dominated proton insertion from weakly acidic zinc electrolyte. The hydrogen bonding network formed with carbonyl and amino groups on the TABQ molecules allows facile proton conduction through the Grotthuss-type mechanism. It guarantees activation energies below 300 meV for charge transfer and proton diffusion. The TABQ cathode delivers a high capacity of 303 mAh g-1 at 0.1 A g-1 in a zinc-organic battery. With the increase of current density to 5 A g-1, 213 mAh g-1 capacity is still preserved with stable cycling for 1000 times. Our work proposes an effective approach towards high performance organic electrode materials.

7.
Chem Commun (Camb) ; 57(51): 6253-6256, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34060576

RESUMO

The energy storage behavior of the Li3V2(PO4)3 cathode in zinc batteries is evaluated. The dissolution or decomposition into vanadium oxide in aqueous electrolytes is revealed. Using the optimal combination of water and acetonitrile solvents in electrolyte, those processes are effectively prevented without sacrificing the Zn2+ de/insertion kinetics. Further investigation demonstrates a water induced phase transformation into a VOPO4 type structure, which is still a polyanion material and preserves the high voltage. It delivers 128 mA h g-1 capacity at 1C with 1.45 V discharge voltage, and 87 mA h g-1 capacity is retained at 10C. A stable cycling is obtained for 1000 cycles.

8.
Chemistry ; 26(37): 8190-8204, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32096256

RESUMO

Various cathode materials have been proposed for high-performance rechargeable batteries. Vanadyl phosphate is an important member of the polyanion cathode family. VOPO4 has seven known crystal polymorphs with tunneled or layered frameworks, which allow facile cation (de)intercalations. Two-electron transfer per formula unit can be realized by using VV /VIV and VIV /VIII redox couples. The electrochemical performance is closely related to the structures of VOPO4 and the types of inserted cations. This Review outlines the crystal structures of VOPO4 polymorphs and their lithiated phases. The research progress of vanadyl phosphate cathode materials for different energy storage systems, including lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, multivalent batteries, and supercapacitors, as well as the related mechanism investigations are summarized. It is hoped that this Review will help with future directions of using vanadyl phosphate materials for energy storage.

9.
ACS Appl Mater Interfaces ; 11(45): 42000-42005, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31647213

RESUMO

The degradation or dendrite formation of zinc metal electrodes has shown to limit the cycle life of rechargeable aqueous zinc batteries, and a few anode protection methods are proposed. We herein demonstrate that, except for external protections, a simple design of an electrolyte can effectively promote stable and facile Zn stripping/plating from/on zinc electrodes. By using Zn(ClO4)2 in the aqueous electrolyte, reversible Zn stripping/plating is achieved for over 3000 h at 1 mA cm-2 current density and 1 mA h cm-2 capacity, superior to the conventional ZnSO4 electrolyte. The overpotential is constant within each cycle and only increases slightly with the increase of current densities. The excellent performance is guaranteed by the controlled formation of a Cl- containing layer, which limits continuous side reactions. The Zn(ClO4)2 electrolyte shows anodic stability up to 2.4 V, and excellent electrochemical performance is achieved for an example cell with the VO2 cathode, confirming the applicability of the electrolyte for Zn batteries.

10.
Angew Chem Int Ed Engl ; 58(45): 16057-16061, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31482627

RESUMO

VOPO4 ⋅x H2 O has been proposed as a cathode for rechargeable aqueous zinc batteries. However, it undergoes significant voltage decay in conventional Zn(OTf)2 electrolyte. Investigations show the decomposition of VOPO4 ⋅x H2 O into VOx in the electrolyte and voltage drops after losing the inductive effect from polyanions.PO4 3- was thus added to shift the decomposition equilibrium. A high concentration of cheap, highly soluble ZnCl2 salt in the electrolyte further prevents VOPO4 ⋅x H2 O dissolution. The cathode shows stable capacity and voltage retentions in 13 m ZnCl2 /0.8 m H3 PO4 aqueous electrolyte, in direct contrast to that in Zn(OTf)2 where the decomposition product VOx provides most electrochemical activity over cycling. Sequential H+ and Zn2+ intercalations into the structure are revealed, delivering a high capacity (170 mAh g-1 ). This work shows the potential issue with polyanion cathodes in zinc batteries and proposes an effective solution using fundamental chemical principles.

11.
Angew Chem Int Ed Engl ; 57(50): 16359-16363, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30307094

RESUMO

Rechargeable aqueous zinc batteries are promising energy-storage systems for grid applications. Highly conductive polyaniline (PANI) is a potential cathode, but it tends to deactivate in electrolytes with low acidity (i.e. pH >1) owing to deprotonation of the polymer. In this study, we synthesized a sulfo-self-doped PANI electrode by a facile electrochemical copolymerization process. The -SO3 - self-dopant functions as an internal proton reservoir to ensure a highly acidic local environment and facilitate the redox process in the weakly acidic ZnSO4 electrolyte. In a full zinc cell, the self-doped PANI cathode provided a high capacity of 180 mAh g-1 , excellent rate performance of 70 % capacity retention with a 50-fold current-density increase, and a long cycle life of over 2000 cycles with coulombic efficiency close to 100 %. Our study opens a door for the use of conducting polymers as cathode materials for high-performance rechargeable zinc batteries.

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