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1.
Adv Sci (Weinh) ; 11(20): e2307995, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38468444

RESUMO

Heterogeneous structures and doping strategies have been intensively used to manipulate the catalytic conversion of polysulfides to enhance reaction kinetics and suppress the shuttle effect in lithium-sulfur (Li-S) batteries. However, understanding how to select suitable strategies for engineering the electronic structure of polar catalysts is lacking. Here, a comparative investigation between heterogeneous structures and doping strategies is conducted to assess their impact on the modulation of the electronic structures and their effectiveness in catalyzing the conversion of polysulfides. These findings reveal that Co0.125Zn0.875Se, with metal-cation dopants, exhibits superior performance compared to CoSe2/ZnSe heterogeneous structures. The incorporation of low Co2+ dopants induces the subtle lattice strain in Co0.125Zn0.875Se, resulting in the increased exposure of active sites. As a result, Co0.125Zn0.875Se demonstrates enhanced electron accumulation on surface Se sites, improved charge carrier mobility, and optimized both p-band and d-band centers. The Li-S cells employing Co0.125Zn0.875Se catalyst demonstrate significantly improved capacity (1261.3 mAh g-1 at 0.5 C) and cycle stability (0.048% capacity delay rate within 1000 cycles at 2 C). This study provides valuable guidance for the modulation of the electronic structure of typical polar catalysts, serving as a design directive to tailor the catalytic activity of advanced Li-S catalysts.

2.
Zookeys ; 1149: 1-15, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250914

RESUMO

Recent studies have revealed that the Kerivouladepressa complex should be divided into two species, K.depressa distributed mainly in Myanmar, Vietnam, Laos and Cambodia, and K.dongduongana found only in the Annamite Mountains of Vietnam, Laos and Cambodia. In November 2018 and April 2019, 24 woolly bats were collected by two-band harp traps in Xishuangbanna, Yunnan, China. Based on morphological, morphometric, and phylogenetic (COI, Cytb, and RAG2 gene sequences) analyses, these bats were identified as K.depressa and K.dongduongana, representing two new species records for the country. Including the new records, six Kerivoula species have been recorded in China, namely K.depressa, K.dongduongana, K.furva, K.kachinensis, K.picta and K.titania. To facilitate their identification and biological research in the future, we have provided an up-to-date key to all Kerivoula species occurring in China.

3.
ACS Appl Mater Interfaces ; 15(2): 2881-2890, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36608156

RESUMO

Li-rich Mn-based layered oxides are proposed to be candidates for high-energy Li-ion batteries. However, their large-scale production is still hampered by poor rate capability and severe voltage decay. It was mainly attributed to the irreversible oxygen loss, which induces transition metal ion migration, electrolyte consumption, and structural evolution. Herein, we propose an effective strategy of phosphorylation, in which the phosphate ion is induced to remove the surface labile oxygen. It urges the Li2MnO3 component to transform to the spinel-like structure and promotes the anionic redox process, thus facilitating lithium-ion diffusion and improving structural stability. As a result, the Li2MnO3 component is more prone to be activated, with the capacity increased by 18% in comparison with the pristine one. It also exhibits a superior capacity retention of 86.1% after 150 extended cycles and better rate performance delivering a capacity of 148.1 mA h g-1 even at 10 C. The effective phosphorylation opens a new way to tune anion redox chemistry and obtain structurally stable materials.

4.
Adv Mater ; 34(47): e2206039, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36165216

RESUMO

The anionic redox reaction (ARR) has attracted extensive attention due to its potential to enhance the reversible capacity of cathode materials in Li/Na-ion batteries (LIBs/SIBs). However, the understanding of its activation mechanism is still limited by the insufficient mastering of the underlying thermodynamics and kinetics. Herein, a series of Mg/Li/Zn-substituted Nax MnO2 and Lix MnO2 cathode materials are designed to investigate their ARR behaviors. It is found that the ARR can be activated in only Li-substituted Lix MnO2 and not for Mg- and Zn-substituted ones, while all Mg/Li/Zn-substituted Nax MnO2 cathode materials exhibit ARR activities. Combining theoretical calculations with experimental results, such a huge difference between Li and Na cathodes is closely related to the migration of substitution ions from the transition metal layer to the alkali metal layer in a kinetic aspect, which generates unique Li(Na)-O-□TM and/or □Li/ Na -O-□TM configurations and reducing reaction activation energy to trigger the ARR. Based on these findings, an ion-migration mechanism is proposed to explain the different ARR behaviors between the Nax MnO2 and Lix MnO2 , which can not only reveal the origin of ARR in the kinetic aspect, but also provide a new insight for the development of high-capacity metal oxide cathode materials for LIBs/SIBs.

5.
Angew Chem Int Ed Engl ; 61(27): e202203698, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35441768

RESUMO

Capacity fading and voltage decay is one of the biggest obstacles for the practical application of Li-rich layered oxides due to the serious surface-related detrimental reactions. Herein, we develop a versatile and scalable method to construct a robust surface-integrated structure. All the designed samples deliver outstanding capacity and voltage stability, among which the Zn-treated sample possesses the best electrochemical performance. Its capacity retention is larger than 90 % after 400 cycles with a voltage decay ratio as small as 0.73 mV per cycle. What is more, the rules of surface-integrated structure with different cations in terms of capacity and voltage stability is further deciphered by combining with density function theory (DFT) calculations. It is found that to obtain advanced Li-rich layered oxide cathodes, cations in Li-sites should firstly ensure the binding energy of the surface-integrated structure in a lower level and then provide Bader charge for the nearest O atoms as small as possible.

6.
Medicine (Baltimore) ; 100(12): e25241, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33761717

RESUMO

BACKGROUND: There are no clinical trials evaluating the efficacy of combined music and Tai Chi therapy for patients with major depression. Therefore, the primary objective of the present study was to evaluate the efficacy of Tai Chi and music therapy on psychological status and quality of life among patients with major depressive disorder in China. METHODS: This work is a part of a comprehensive research project to assess and provide intervention that potentially improves psychological status and quality of life among patients with major depressive disorder. This research project has been received ethical approval from the Medical Research and Ethics Committee in Taizhou Second People's Hospital (no. tzey2020023). After the introductory briefing, the acceptance to take the presession questionnaire implied the participant's consent to participate in the study. Eligible participants are divided into 3 groups according to completely randomized design: combined group (music therapy + Tai Chi), music therapy alone group, and Tai Chi alone group. The analyses will be performed using SPSS 22.0.0 (SPSS Inc, Chicago, IL). RESULTS: This protocol will provide a reliable theoretical basis for the following research. CONCLUSION: The sample came from a single health center. Therefore, the results cannot be generalized for the entire population. TRIAL REGISTRATION: This study protocol was registered in Research Registry (researchregistry6597).


Assuntos
Transtorno Depressivo Maior , Musicoterapia/métodos , Qualidade de Vida , Tai Chi Chuan , Adulto , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/psicologia , Transtorno Depressivo Maior/terapia , Feminino , Humanos , Masculino , Música/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Tai Chi Chuan/métodos , Tai Chi Chuan/psicologia , Resultado do Tratamento
7.
Chem Commun (Camb) ; 57(28): 3512-3515, 2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33690759

RESUMO

Uniform distribution of Li2MnO3 and LiMO2 components in a Co-free Li-rich layered oxide is achieved by treating precursors with NH3·H2O, which expands the lattice parameter and promotes the activation of Li2MnO3, resulting in excellent electrochemical performance. What's more, it also contributes to the storage stability of Li-rich layered oxides.

8.
Chem Commun (Camb) ; 56(80): 12009-12012, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32901619

RESUMO

The effect of fluoride coatings, an effective approach to suppress HF corrosion, on the cycling stability of NCM523 cathodes is systematically studied. It is the first study to reveal that fluoride coatings significantly restrain interfacial reactions when, simultaneously, the fluoride suspension possesses an appropriate pH (near 4.0) and there is a small cation ionic radius.

9.
Angew Chem Int Ed Engl ; 59(20): 7778-7782, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32030866

RESUMO

Voltage decay and capacity fading are the main challenges for the commercialization of Li-rich Mn-based layered oxides (LLOs). Now, a three-in-one surface treatment is designed via the pyrolysis of urea to improve the voltage and capacity stability of Li1.2 Mn0.6 Ni0.2 O2 (LMNO), by which oxygen vacancies, spinel phase integration, and N-doped carbon nanolayers are synchronously built on the surface of LMNO microspheres. Oxygen vacancies and spinel phase integration suppress irreversible O2 release and help lithium ion diffusion, while N-doped carbon nanolayer mitigates the corrosion of electrolyte with excellent conductivity. The electrochemical performance of LMNO after the treatment improves significantly; the capacity retention rate after 500 cycles at 1 C is still as high as 89.9 % with a very small voltage fading rate of 1.09 mV cycle-1 . This three-in-one surface treatment strategy can suppress the voltage decay and capacity fading of LLOs.

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