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1.
Angew Chem Int Ed Engl ; : e202407118, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849318

ABSTRACT

Cross-electrophile coupling (XEC) between aryl halides and alkyl halides is a streamlined approach for C(sp2)-C(sp3) bond construction, which is highly valuable in medicinal chemistry. Based on a key NiII aryl amido intermediate, we developed a highly selective and scalable Ni-catalyzed electrochemical XEC reaction between (hetero)aryl halides and primary and secondary alkyl halides. Experimental and computational mechanistic studies indicate that an amine secondary ligand slows down the oxidative addition process of the Ni-polypyridine catalyst to the aryl bromide and a NiII aryl amido intermediate is formed in-situ during the reaction process. The relatively slow oxidative addition is beneficial for enhancing the selectivity of the XEC reaction. The NiII aryl amido intermediate stabilizes the NiII-aryl species to prevent the aryl-aryl homo-coupling side reactions and acts as a catalyst to activate the alkyl bromide substrates. This electrosynthesis system provides a facile, practical, and scalable platform for the formation of (hetero)aryl-alkyl bonds using standard Ni catalysts under mild conditions. The mechanistic insights from this work could serve as a great foundation for future studies on Ni-catalyzed cross-couplings.

2.
iScience ; 27(4): 109409, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38577100

ABSTRACT

China has promoted campus soccer for over a decade due to its potential health benefits. The study aimed to explore soccer knowledge (SK), soccer attitude (SA), soccer practice (SP), and health status among Chinese freshmen and sophomore undergraduates who had received campus soccer education. Of the 7419 participants, 1,069 were valid and included in the analysis. Structural equation modeling (SEM) results indicated SK is positively associated with SA (p < 0.001), but negatively with SP (p < 0.01). SA was positively linked to SP (p < 0.001). SK indirectly affected SP through SA (Z = 13.677). Random forest-tree-structured Parzen estimators (RF-TPE) with SHAP indicated SP holds primary importance with a strong negative impact on health. Additionally, differences in rankings for SK, SA, and SP were observed among gender and urban-rural groups. These results reveal current campus soccer education is suboptimal to health promotion.

3.
BMC Sports Sci Med Rehabil ; 15(1): 143, 2023 Oct 28.
Article in English | MEDLINE | ID: mdl-37898786

ABSTRACT

BACKGROUND: Substitutions are generally used to promote the match performance of the whole team. This study aimed to analyze the performance of substitute players and explore the performance difference among substitute players, completed players, and replaced players across each position. METHODS: Chinese Super Soccer League (CSL) matches in the season 2018 including 5871 individual observation from 395 professional soccer players were analyzed by establishing linear mixed models to quantify the performance difference among substitute players (SP) (n = 1,071), entire match players (EMP) (n = 3,454), and replaced players (RP) (n = 1,346), and then separately for each position (central defenders, fullbacks, central midfielders, wide midfielders, and attackers). RESULTS: The results show SP display higher high intensity distance and sprint distance significantly (p < 0.05) relative to playing time than RP and EMP. SP in offensive positions (attackers, wide midfielders) showed significantly higher (p < 0.05) passing and organizing performance such as passes, ball control, short passes, and long passes than RP or EMP. The scoring performances of central midfielders of SP including goals, shots, and shots on target are significantly higher (p < 0.05) than RP or EMP. Central defenders of SP showed higher shot blocks and pass blocks (p < 0.05) while lower passing and organizing performance (p < 0.05). CONCLUSION: Depending on different playing positions, substitute players could indeed improve physical and technical performance related to scoring, passing, and defending as offensive substitute players can boost organizing performance and substitute defenders enhance defending performance. These could help coaches better understand substitute players' influence on match performance and optimize the substitution tactic.

4.
Sci Rep ; 13(1): 11533, 2023 07 17.
Article in English | MEDLINE | ID: mdl-37460573

ABSTRACT

This study adopts a new approach, SHapley Additive exPlanation (SHAP), to diagnose the table tennis matches based on a hybrid algorithm, namely Long Short-Term Memory-Back Propagation Neural Network (LSTM-BPNN). 100 male singles competitions (8535 rallies) from 2019 to 2022 are analyzed by a hybrid technical-tactical analysis theory, which hybridizes the double three-phase and four-phase evaluation theories. A k-means cluster analysis is conducted to classify 59 players' winning rates into three levels (high, medium, and low). The results show that LSTM-BPNN has excellent performance (MSE = 0.000355, MAE = 0.014237, RMSE = 0.018853, and [Formula: see text] = 0.988311) compared with six typical artificial intelligence algorithms. Using LSTM-BPNN to calculate the SHAP value of each feature, the global results find that the receive-attack and serve-attack phases of the ending match have essential impacts on the mutual winning probabilities. Finally, case applications show that the SHAP can directly obtain each feature importance on one or more matches, which is more objective and reliable than the traditional simulation method. This research explores an innovative way to understand and analyze matches, and these results have implications for the performance analysis of table tennis and related racket sports.


Subject(s)
Athletic Performance , Tennis , Male , Humans , Artificial Intelligence , Neural Networks, Computer , Algorithms
5.
Small ; 19(18): e2206067, 2023 May.
Article in English | MEDLINE | ID: mdl-36720012

ABSTRACT

It is essential but still challenging to design and construct inexpensive, highly active bifunctional oxygen electrocatalysts for the development of high power density zinc-air batteries (ZABs). Herein, a CoFe-S@3D-S-NCNT electrocatalyst with a 3D hierarchical structure of carbon nanotubes growing on leaf-like carbon microplates is designed and prepared through chemical vapour deposition pyrolysis of CoFe-MOF and subsequent hydrothermal sulfurization. Its 3D hierarchical structure shows excellent hydrophobicity, which facilitates the diffusion of oxygen and thus accelerates the oxygen reduction reaction (ORR) kinetic process. Alloying and sulfurization strategies obviously enrich the catalytic species in the catalyst, including cobalt or cobalt ferroalloy sulfides, their heterojunction, core-shell structure, and S, N-doped carbon, which simultaneously improve the ORR/OER catalytic activity with a small potential gap (ΔE = 0.71 V). Benefiting from these characteristics, the corresponding liquid ZABs show high peak power density (223 mW cm-2 ), superior specific capacity (815 mA h gZn -1 ), and excellent stability at 5 mA cm-2 for ≈900 h. The quasi-solid-state ZABs also exhibit a very high peak power density of 490 mW cm-2 and an excellent voltage round-trip efficiency of more than 64%. This work highlights that simultaneous composition optimization and microstructure design of catalysts can effectively improve the performance of ZABs.

6.
BMC Sports Sci Med Rehabil ; 14(1): 208, 2022 Dec 09.
Article in English | MEDLINE | ID: mdl-36494746

ABSTRACT

BACKGROUND: Due to the COVID-19 pandemic, the 2020 season Chinese Super League (CSL) was held in neutral venues, this study aims to analyse the impact of removing home advantage (HA) in CSL. METHOD: 240 games of the CSL 2019 season (home and away double round-robin system) and 160 games of the 2020 season (in neutral venues) were analysed. 27 technical and tactical performance indicators were involved as dependent variables. A multiple linear regression model was established to analyse the influence of removing HA on the performance indicators. RESULTS: After moving from home stadium to neutral venue in 2020 season, goal, shot, shot on target, shot from outside box, shot from inside box, shot on target from inside box, corner kick, key pass, cross, breakthrough, tackle decreased significantly (p < 0.05), while yellow card and foul increased steeply (p < 0.05). Comparing with playing away match, in neutral venue, free kicks and pass accuracy enhanced radically (p < 0.05), while tackle, clearance and block shot dropped noticeably (p < 0.05). CONCLUSION: When removing HA and playing in the neutral venue, teams' performance dropped significantly. This study confirmed the positive impact of HA on the teams' performance and may help elite football teams make proper playing strategies regarding different match locations.

7.
Front Psychol ; 13: 1038733, 2022.
Article in English | MEDLINE | ID: mdl-36467172

ABSTRACT

Purpose: In football, attacking has seen evolving for decades and attacking pattern detection is an important topic in this sport. The purpose of this study was to identify the general and threatening attacking patterns of different playing styles in world top football matches, which represented the latest evolvement of soccer attacking. Methods: Attacking sequence data of the top three teams from 21 matches in the 2018 World Cup were collected. The three teams were classified into two playing styles according to a previous study, France was a direct-play team, and Croatia and Belgium were possession-play teams. The football field was divided into 12 zones and Markov transition matrix-based zone models were applied to assess the attacking pattern in the 21 matches. Both descriptive analysis and simulative analysis were conducted using this model. Results: The results revealed that (1) flanker attacks were frequently taken among all three teams, and possession playing teams (Croatia and Belgium) played more often than direct playing teams (France) in their center of the midfield zone and (2) forward passes across/through zones toward the middle of attacking quarter (A1/4) have a positive impact of creating a chance of a goal. Conclusion: Using Markov transition matrix, general and threatening attacking patterns were found. The combination of possession play and counterattack was a new trend that emerged in the 2018 World Cup. These findings can help coaches to develop corresponding strategies when facing opponents of different playing styles.

8.
Front Neurol ; 13: 929781, 2022.
Article in English | MEDLINE | ID: mdl-36158946

ABSTRACT

Psychiatric and neurodegenerative diseases, including major depression disorder (MDD), bipolar disorder, and Alzheimer's disease, are a burden to society. Deficits of adult hippocampal neurogenesis (AHN) have been widely considered the main hallmark of psychiatric diseases as well as neurodegeneration. Herein, exploring applicable targets for improving hippocampal neural plasticity could provide a breakthrough for the development of new treatments. Emerging evidence indicates the broad functions of mitochondria in regulating cellular behaviors of neural stem cells, neural progenitors, and mature neurons in adulthood could offer multiple neural plasticities for behavioral modulation. Normalizing mitochondrial functions could be a new direction for neural plasticity enhancement. Exercise, a highly encouraged integrative method for preventing disease, has been indicated to be an effective pathway to improving both mitochondrial functions and AHN. Herein, the relative mechanisms of mitochondria in regulating neurogenesis and its effects in linking the effects of exercise to neurological diseases requires a systematic summary. In this review, we have assessed the relationship between mitochondrial functions and AHN to see whether mitochondria can be potential targets for treating neurological diseases. Moreover, as for one of well-established alternative therapeutic approaches, we summarized the evidence to show the underlying mechanisms of exercise to improve mitochondrial functions and AHN.

9.
Front Psychol ; 13: 907336, 2022.
Article in English | MEDLINE | ID: mdl-35859824

ABSTRACT

This study explored factors that influence actual playing time by comparing the Chinese Super League (CSL) and English Premier League (EPL). Eighteen factors were classified into anthropogenic and non-anthropogenic factors. Fifty CSL matches (season 2019) and 50 EPL matches (season 2019-2020) were analyzed. An independent sample t-test with effect size (Cohen's d) at a 95% confidence interval was used to evaluate differences in the influencing factors between the CSL and EPL. Two multiple linear regression models regarding the CSL and EPL were conducted to compare the influencing factors' impact on actual playing time. The results showed that the average actual playing time (p < 0.05, 0.6 < ES = 0.610 < 1.2) and average game density (p < 0.05, 0.2 < ES = 0.513 < 0.6) in the EPL were significantly higher than in the CSL. The average time per game for general fouls (p < 0.05, 1.2 < ES = 1.245 < 2.0) and minor injuries (p < 0.05, 0.2 < ES = 0.272 < 0.6) in the CSL was significantly higher than in the EPL. The average time allocated to off-field interferences in the CSL was significantly higher than in the EPL, while the average time allocated to throw-ins (out-of-bounds) in the CSL was significantly lower than in the EPL (p < 0.05, 0.2 < ES = 0.556 < 0.6). The study showed that actual playing time in CSL games was more affected by anthropogenic factors than in the case of EPL games, while both leagues were equally affected by non-anthropogenic factors. This study provides a reference for coaches to design effective training and formulate game strategies for elite soccer leagues.

10.
Materials (Basel) ; 15(11)2022 May 27.
Article in English | MEDLINE | ID: mdl-35683147

ABSTRACT

Understanding the relationships between the local structures and physical properties of low-dimensional ferroelectrics is of both fundamental and practical importance. Here, pressure-induced enhancement in the photocurrent of SbSI is observed by using pressure to regulate the lone-pair electrons (LPEs). The reconfiguration of LPEs under pressure leads to the inversion symmetry broken in the crystal structure and an optimum bandgap according to the Shockley-Queisser limit. The increased polarization caused by the stereochemical expression of LPEs results in a significantly enhanced photocurrent at 14 GPa. Our research enriches the foundational understanding of structure-property relationships by regulating the stereochemical role of LPEs and offers a distinctive approach to the design of ferroelectric-photovoltaic materials.

11.
Front Psychol ; 13: 1054275, 2022.
Article in English | MEDLINE | ID: mdl-36619136

ABSTRACT

Purpose: School health education is an effective strategy for cultivating adolescent physical exercise habits by transmitting healthy knowledge; it helps to form healthy behaviours and encourages students to participate in physical exercise. The purpose of this study was to explore the relationship between school health education and student participation in physical exercise. Methods: CEPS (China Education Penal Survey, 2014-2015) survey data were used to empirically analyse the impact of school health education on the time that students spend on physical exercise and the underlying mechanism of influence. Results: The results showed that receiving a school health education increased the time that students spent on physical exercise. 1) Compared with receiving health education in only primary school or secondary school, receiving health education in both primary and secondary school had a greater impact on students spending time on physical exercise. 2) Receiving a school health education improved the time that students spend on physical exercise by improving students' health perception and their sports interests. 3) Receiving a school health education had a more obvious impact on the physical exercise time of male students, nonrural resident students, and students from multi-child households. These findings can provide a reference for the seasonable settings of health education curriculum in schools.

12.
Front Psychol ; 12: 722200, 2021.
Article in English | MEDLINE | ID: mdl-34659035

ABSTRACT

The purpose of this study was to investigate the impact of high (HPBPT) and low percentage ball possession teams (LPBPT) on physical and technical-tactical performance indicators in the Chinese Football Super League (CSL). Eight physical performance indicators and 26 technical-tactical performance indicators from all 240 matches from season 2018 were analyzed, as well as three contextual variables (team strength, quality of opposition, and match location). Players were divided according to five positions: fullbacks, central defenders, wide midfielders, central midfielders, and attackers. A k-means cluster analysis was conducted to classify all match observations into two groups: HPBPT (n = 229) and LPBPT (n = 251). A mixed linear model was fitted with contextual variables as covariates. When significant interactions or main effects were detected, a post hoc comparison was used to compare physical and technical/tactical differences between HPBPT and LPBPT. Results showed that central defenders and fullbacks covered more high-intensity and sprint running distance in the high possession teams, while wide midfielders and forward covered more high-intensity and sprint running distance in the low possession teams. Meanwhile, players from high ball possession teams were strong in technical indicators, especially in attacking organization. These results may help coaches to understand current football development trends and develop suitable training plans and tests for elite football players.

13.
Front Psychol ; 12: 662708, 2021.
Article in English | MEDLINE | ID: mdl-34122250

ABSTRACT

The aim of this study was to explore the effect of scoring first on match outcomes in the Chinese Football Super League (CSL). A total of 1,116 matches in which at least one goal was scored from the 2014 to 2018 seasons were collected. Match outcomes, absolute goal differences, the minute of the first goal, match locations, and teams' budgets were analyzed. A team's budget was measured in terms of a team's value at the beginning of the season, and teams were clustered into two groups (high and low budget with means of 50.77 and 13.77 million dollars, respectively). A descriptive analysis was conducted, and two generalized linear models (a multinomial logit model and a Poisson model; p < 0.05) were applied. The results showed a favorable outcome for the team that scored first both in match outcome and goal difference. Regarding the teams that scored first, 66.31% won their matches, 20.70% achieved a draw, and 12.99% lost. Specifically, home teams were more likely to win (13.42%) and less likely to lose (9.52%) or draw (3.90%) than away teams. Home teams also had a higher likelihood of obtaining a larger goal difference. Higher budget teams were more likely to win (14.90%) and less likely to lose (9.75%) or draw (5.14%) than low-budget teams. Additionally, for each minute, the team scores closer to the end of the match, and the average probability of winning increased by 0.0028. These findings can guide the strategies of coaches in different match scenarios according to the match location and the opponent's quality.

14.
Article in English | MEDLINE | ID: mdl-31963397

ABSTRACT

It is well known that increasing participation in physical activities is not only positive for individual health promotion, but also beneficial for community-level public health by enhancing the individual's social well-being by facilitating social inclusion. Although the provision of community sports affects participation in physical activities, the magnitude and direction of this effect are still not clear. Under this circumstance, this paper examined the effects of community sports provision on social inclusion and public health using the micro-level data from a household survey conducted in eight provinces of rural China. For the purpose of this paper, the degree of social inclusion was proxied by participation in community sports, while public health was measured by the probability of getting ill for members of each household. The empirical results show that community sports provision was partially effective in promoting inclusion and health in rural areas. Specifically, constructing public sports facilities significantly increases participation in community sports and decreases the risk of getting ill. In contrast, organizing public sports activities increases the opportunity for households to play sports. Nonetheless, it does not promote public health. Equally important is that economic growth (reflected in the increase in income level) may enhance public health through advancing medical technologies and improving sanitary conditions instead of encouraging participation in community sports.


Subject(s)
Community Participation/statistics & numerical data , Health Promotion , Public Health/statistics & numerical data , Social Participation/psychology , Sports/statistics & numerical data , China , Exercise , Humans
15.
Angew Chem Int Ed Engl ; 58(21): 6967-6971, 2019 May 20.
Article in English | MEDLINE | ID: mdl-30834664

ABSTRACT

Mg batteries are a promising energy storage system because of the physicochemical merits of Mg as an anode material. However, the lack of electrochemically and chemically stable Mg electrolytes impedes the development of Mg batteries. In this study, a newly designed chloride-free Mg perfluorinated pinacolatoborate, Mg[B(O2 C2 (CF3 )4 )2 ]2 (abbreviated as Mg-FPB), was synthesized by a convenient method from commercially available reagents and fully characterized. The Mg-FPB electrolyte delivered outstanding electrochemical performance, specifically, 95 % Coulombic efficiency and 197 mV overpotential, enabling reversible Mg deposition, and an anodic stability of up to 4.0 V vs. Mg. The Mg-FPB electrolyte was applied to assemble a high voltage, rechargeable Mg/MnO2 battery with a discharge capacity of 150 mAh g-1 .

16.
Dalton Trans ; 48(15): 4867-4878, 2019 Apr 09.
Article in English | MEDLINE | ID: mdl-30882832

ABSTRACT

The interactions between pendant amines in the second coordination sphere and ligands in the first coordination sphere are important for understanding the structures and reactivity of complexes containing PR2NR'2 ligands, which have been shown to be highly active H2 oxidation/production catalysts. A series of [Fe(PPh2NBn2)2(X)(Y)]n+ complexes have been prepared and structurally characterized. These complexes have two different ligands with which the pendant amines of the diphosphine ligand can interact. The solid state structure of cis-Fe(PPh2NBn2)2Cl2 reveals that the six-membered rings adjacent to the P atoms are in a boat confirmation, resulting in close NP distances that suggests the P atoms have a greater affinity for the lone pair of electrons on the N atom than chloride ligands. Similarly, boat conformations are observed for both rings adjacent to the hydride ligands of trans-[HFe(PPh2NBn2)2(CH3CN)]+ and trans-HFe(PPh2NBn2)2Cl, resulting in short NH distances. Spectroscopic and computational studies of trans-[HFe(PPh2NBn2)2(CO)]+, trans-[HFe(PPh2NBn2)(PPh2NBn2H)(CO)]2+, and trans-[HFe(PPh2NBn2)2(H2)]+ indicate the complexes are more stable when the pendant amines in boat conformations are adjacent to the hydride ligand. These data suggest an attractor ordering of H- > CO > H2 > PR3 > Cl- ∼ CH3CN.

17.
Angew Chem Int Ed Engl ; 57(1): 231-235, 2018 01 02.
Article in English | MEDLINE | ID: mdl-29181865

ABSTRACT

Extending the conjugation of viologen by a planar thiazolo[5,4-d]thiazole (TTz) framework and functionalizing the pyridinium with hydrophilic ammonium groups yielded a highly water-soluble π-conjugation extended viologen, 4,4'-(thiazolo[5,4-d]thiazole-2,5-diyl)bis(1-(3-(trimethylammonio)propyl)pyridin-1-ium) tetrachloride, [(NPr)2 TTz]Cl4 , as a novel two-electron storage anolyte for aqueous organic redox flow battery (AORFB) applications. Its physical and electrochemical properties were systematically investigated. Paired with 4-trimethylammonium-TEMPO (NMe -TEMPO) as catholyte, [(NPr)2 TTz]Cl4 enables a 1.44 V AORFB with a theoretical energy density of 53.7 Wh L-1 . A demonstrated [(NPr)2 TTz]Cl4 /NMe -TEMPO AORFB delivered an energy efficiency of 70 % and 99.97 % capacity retention per cycle.

18.
J Sports Sci ; 35(8): 806-811, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27267568

ABSTRACT

This retrospective study focuses on the comparison of different predictive models based on the results of a talent identification test battery for female gymnasts. We studied to what extent these models have the potential to optimise selection procedures, and at the same time reduce talent development costs in female artistic gymnastics. The dropout rate of 243 female elite gymnasts was investigated, 5 years past talent selection, using linear (discriminant analysis) and non-linear predictive models (Kohonen feature maps and multilayer perceptron). The coaches classified 51.9% of the participants correct. Discriminant analysis improved the correct classification to 71.6% while the non-linear technique of Kohonen feature maps reached 73.7% correctness. Application of the multilayer perceptron even classified 79.8% of the gymnasts correctly. The combination of different predictive models for talent selection can avoid deselection of high-potential female gymnasts. The selection procedure based upon the different statistical analyses results in decrease of 33.3% of cost because the pool of selected athletes can be reduced to 92 instead of 138 gymnasts (as selected by the coaches). Reduction of the costs allows the limited resources to be fully invested in the high-potential athletes.


Subject(s)
Aptitude , Discriminant Analysis , Gymnastics/economics , Neural Networks, Computer , Costs and Cost Analysis , Female , Humans , Retrospective Studies
19.
J Chem Theory Comput ; 11(1): 205-14, 2015 Jan 13.
Article in English | MEDLINE | ID: mdl-26574218

ABSTRACT

A series of different density functional theory (DFT) methodologies (24 functionals) in conjunction with a variety of six different basis sets (BSs) was employed to investigate the relative stabilities in the oxygenated isomers of diiron complexes that mimic the active site of [FeFe]-hydrogenase: (µ-pdt)[Fe(CO)2L][Fe(CO)2L'] (pdt = propane-1,3-dithiolate; L = L' = CO (1); L = PPh3, L' = CO (2); L = PMe3, L' = CO (3); L = L' = PMe3 (4). Although the enzyme may have a variety of possible sites for oxygenation, the model complexes would necessarily be oxygenated at either the diiron bridging site (µ-O) or at a sulfur (SO). Previous DFT studies with both B3LYP and TPSS functionals predicted a more stable µ-O isomer, whereas only the SO isomer was observed experimentally (J. Am. Chem. Soc. 2009, 131, 8296-8307). Here, further calculations reveal that the relative stabilities of the SO and µ-O isomers are extremely sensitive to the choice of the functional, moderately sensitive to the S basis set, but not to the Fe basis set. The relative free energies [Gsolv(µ-O) - Gsolv(SO)] range from +10 to -60 kcal/mol, a range much larger than what would have been expected on the basis of the previous DFT results. Benchmarking of these results against coupled cluster with single and double excitation calculations, which predict that the SO isomer is favored, shows that the best performing functionals are BP86 and PBE0, while B97-D, M05, and SVWN overestimate and B2PLYP, BH&HLYP, BMK, M06-HF, and M06-2X underestimate the energy differences. Most of the variation occurs with the µ-O isomer and appears to be associated with a functional's ability to predict the strength of the Fe-Fe bond in the reactant. With respect to the S basis set, it appears that the S═O bond is sensitive to the nature of the d polarization functions available on the S atom. The S seems to need a d function more diffuse than the d orbital optimized to provide polarization for the S atom alone; that is, S seems to need a d orbital that has strong overlap with the O atom's valence 2p. Other basis functions and the relative position of the PR3 (R = Ph and Me) substituent groups have smaller influences on the free energy differences.

20.
Angew Chem Int Ed Engl ; 54(30): 8684-7, 2015 Jul 20.
Article in English | MEDLINE | ID: mdl-25891480

ABSTRACT

Nonaqueous redox flow batteries hold the promise of achieving higher energy density because of the broader voltage window than aqueous systems, but their current performance is limited by low redox material concentration, cell efficiency, cycling stability, and current density. We report a new nonaqueous all-organic flow battery based on high concentrations of redox materials, which shows significant, comprehensive improvement in flow battery performance. A mechanistic electron spin resonance study reveals that the choice of supporting electrolytes greatly affects the chemical stability of the charged radical species especially the negative side radical anion, which dominates the cycling stability of these flow cells. This finding not only increases our fundamental understanding of performance degradation in flow batteries using radical-based redox species, but also offers insights toward rational electrolyte optimization for improving the cycling stability of these flow batteries.

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