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1.
Small ; : e2400767, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38676351

RESUMEN

Fluorides are viewed as promising conversion-type Li-ion battery cathodes to meet the desired high energy density. FeOF is a typical member of conversion-type fluorides, but its major drawback is sluggish kinetics upon deep discharge. Herein, a heterostructured FeOF-MXene composite (FeOF-MX) is demonstrated to overcome this limitation. The rationally designed FeOF-MX electrode features a microsphere morphology consisting of closely packed FeOF nanoparticles, providing fast transport pathways for lithium ions while a continuous wrapping network of MXene nanosheets ensures unobstructed electron transport, thus enabling high-rate lithium storage with enhanced pseudocapacitive contribution. In/ex situ characterization techniques and theoretical calculations, both reveal that the lithium storage mechanism in FeOF arises from a hybrid intercalation-conversion process, and strong interfacial interactions between FeOF and MXene promote Li-ion adsorption and migration. Remarkably, through demarcating the conversion-type reaction with a controlled potential window, a symmetric full battery with prelithiated FeOF-MX as both cathode and anode is fabricated, achieving a high energy density of 185.5 Wh kg-1 and impressive capacity retention of 88.9% after 3000 cycles at 1 A g-1. This work showcases an effective route toward high-performance MXene engineered fluoride-based electrodes and provides new insights into constructing symmetric batteries yet with high-energy/power densities.

2.
J Colloid Interface Sci ; 664: 96-106, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38460388

RESUMEN

The means of structural hybridization such as heterojunction construction and carbon-coating engineering for facilitating charge transfer and electron transport are considered viable strategies to address the challenges associated with the low rate capability and poor cycling stability of sulfide-based anodes in potassium-ion batteries (PIBs). Motivated by these concepts, we have successfully prepared a hydrangea-like bimetallic sulfide heterostructure encapsulated in nitrogen-doped carbon (FMS@NC) using a simple solvothermal method, followed by poly-dopamine wrapping and a one-step sulfidation/carbonization process. When served as an anode for PIBs, this FMS@NC demonstrates a high specific capacity (585 mAh g-1 at 0.05 A/g) and long cycling stability. Synergetic effects of mitigated volume expansions and enhanced conductivity that are responsbile for such high performance have been verified to originate from the heterostructured sulfides and the N-doped carbon matrix. Meanwhile, comprehensive characterization reveals existence of an intercalation-conversion hybrid K-ion storage mechanism in this material. Impressively, a K-ion capacitor with the FMS@NC anode and a commercial activated carbon cathode exhibits a superior energy density of up to 192 Wh kg-1, a high power density, and outstanding cycling stability. This study provides constructive guidance for designing high-performance and durable potassium-ion storage anodes for next-generation energy storage devices.

3.
Psychol Res Behav Manag ; 17: 1087-1102, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38495087

RESUMEN

Background: The emergence of new technologies, such as artificial intelligence (AI), may manifest as technology panic in some people, including adolescents who may be particularly vulnerable to new technologies (the use of AI can lead to AI dependence, which can threaten mental health). While the relationship between AI dependence and mental health is a growing topic, the few existing studies are mainly cross-sectional and use qualitative approaches, failing to find a longitudinal relationship between them. Based on the framework of technology dependence, this study aimed to determine the prevalence of experiencing AI dependence, to examine the cross-lagged effects between mental health problems (anxiety/depression) and AI dependence and to explore the mediating role of AI use motivations. Methods: A two-wave cohort program with 3843 adolescents (Male = 1848, Mage = 13.21 ± 2.55) was used with a cross-lagged panel model and a half-longitudinal mediation model. Results: 17.14% of the adolescents experienced AI dependence at T1, and 24.19% experienced dependence at T2. Only mental health problems positively predicted subsequent AI dependence, not vice versa. For AI use motivation, escape motivation and social motivation mediated the relationship between mental health problems and AI dependence whereas entertainment motivation and instrumental motivation did not. Discussion: Excessive panic about AI dependence is currently unnecessary, and AI has promising applications in alleviating emotional problems in adolescents. Innovation in AI is rapid, and more research is needed to confirm and evaluate the impact of AI use on adolescents' mental health and the implications and future directions are discussed.

4.
Adv Mater ; 36(21): e2312927, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38373357

RESUMEN

All-solid-state lithium batteries (ASSLBs) face critical challenges of low cathode loading and poor rate performances, which handicaps their energy/power densities. The widely-accepted aim of high ionic conductivity and low interfacial resistance seems insufficient to overcome these challenges. Here, it is revealed that an efficient ion percolating network in the cathode exerts a more critical influence on the electrochemical performance of ASSLBs. By constructing vertical alignment of Li0.35La0.55TiO3 nanowires (LLTO NWs) in solid-state cathode through magnetic manipulation, the ionic conductivity of the cathode increases twice compared with the cathode consisted of randomly distributed LLTO NWs. The all-solid-state LiFePO4/Li cells using poly(ethylene oxide) as the electrolyte is able to deliver high capacities of 151 mAh g-1 (2 C) and 100 mAh g-1 (5 C) at 60 °C, and a room-temperature capacity of 108 mAh g-1 can be achieved at a charging rate of 2 C. Furthermore, the cell can reach a high areal capacity of 3 mAh cm-2 even with a practical LFP loading of 20 mg cm-2. The universality of this strategy is also presented showing the demonstration in LiNi0.8Co0.1Mn0.1O2 cathodes. This work offers new pathways for designing ASSLBs with improved energy/power densities.

5.
J Colloid Interface Sci ; 661: 671-680, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38310773

RESUMEN

Metallic sulfides are currently considered as ideal anode materials for potassium-ion batteries by virtue of their high specific capacities. However, their low intrinsic electronic conductivity, large volume variation and dissolution of polysulfides in electrochemical reactions hinder their further development toward practical applications. Here, we propose an effective structural design strategy by encapsulating CoS2/SnS2 in sulfur-doped carbon layers, in which internal voids are created to relieve the strain in the CoS2/SnS2 core, while the sulfur-doped carbon layer serves to improve the electron transport and inhibit the dissolution of polysulfides. These features enable the as-designed anode to deliver a high specific capacity (520 mAh/g at 0.1 A/g), a high rate capability (185 mA h g-1 at 10 A/g) and lifespan (0.016 % capacity loss per cycle up to 1500 cycles). Our comprehensive electrochemical characterization reveals that the heterostructure of CoS2/SnS2 not only promotes charge transfer at its interfaces, but also enhances the rate of K+ diffusion. Additionally, potassium-ion capacitors based on this novel anode are able to attain an energy density up to 162 Wh kg-1 and âˆ¼ 96 % capacity retention after 3000 cycles at 10 A/g.The demonstrated design rule combining morphological and structural engineering strategies sheds light on the development of advanced electrodes for high performance potassium-based energy storage devices.

6.
Adv Mater ; 36(1): e2307219, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37699330

RESUMEN

Aqueous Zn metal batteries are promising candidates for large-scale energy storage due to their intrinsic advantages. However, Zn tends to deposit irregularly and forms dendrites driven by the uneven space electric field distribution near the Zn-electrolyte interphase. Herein it is demonstrated that trace addition of Co single atom anchored carbon (denoted as CoSA/C) in the electrolyte regulates the microspace electric field at the Zn-electrolyte interphase and unifies Zn deposition. Through preferential adsorption of CoSA/C on the Zn surface, the atomically dispersed Co-N3 with strong charge polarization effect can redistribute the local space electric field and regulate ion flux. Moreover, the dynamic adsorption/desorption of CoSA/C upon plating/stripping offers sustainable long-term regulation. Therefore, Zn||Zn symmetric cells with CoSA/C electrolyte additive deliver stable cycling up to 1600 h (corresponding to a cumulative plated capacity of 8 Ah cm-2 ) at a high current density of 10 mA cm-2 , demonstrating the sustainable feature of microspace electric field regulation at high current density and capacity.

7.
Chem Commun (Camb) ; 60(5): 566-569, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38093681

RESUMEN

To mitigate Zn corrosion, dendrite growth and hydrogen evolution reactions (HER) in Zn-anode based electrochromic devices, hydrophobic CuZn5 alloy was coated on Zn@CuZn with lower nucleation potential, high coulombic efficiency, inhibited HER, and prolonged reversibility, enabling improved switching kinetics and cycling stability in an electrochromic Zn@CuZn||Prussian Blue (PB) device.

8.
Small ; 20(23): e2308484, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38143292

RESUMEN

Prussian blue analogs (PBAs) show great promise as anode materials for potassium-ion batteries (PIBs) due to their high specific capacity. However, PBAs still suffer from the drawbacks of low electronic conductivity and poor structural stability, leading to inadequate rate and cyclic performance. To address these limitations, CoFe PBA nanocubes wrapped with N/S doped carbon network (CoFe PBA@NSC) as anode for PIBs is designed by using thermal-induced in situ conversion strategy. As expected, the structural advantages of nanosized PBA cubes, such as abundant interfaces and large surface area, enable the CoFe PBA@NSC electrode to demonstrate superior rate properties (557 and 131 mAh g-1 at 0.05 and 10 A g-1) and low capacity degradation (0.093% per cycle over 1000 cycles at 0.5 A g-1). Furthermore, several ex situ characterizations revealed the K-ion storage mechanism. Fe+ and Co0 are generated during potassicization, followed by a completely reversible chemical state of iron while some cobalt monomers remained during depotassication. Additionally, the as-built potassium-ion hybrid capacitor based on CoFe PBA@NSC anode exhibits a high energy density of 118 Wh kg-1. This work presents an alternative but promising synthesis route for Prussian blue analogs, which is significant for the advancement of PIBs and other related energy storage devices.

9.
Small Methods ; : e2301355, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-38072620

RESUMEN

Hard-soft carbon hybrid materials, harvesting the expanded interlayer spacing of hard carbon and the high conductivity of soft carbon, hold great promise as anode materials for potassium-ion batteries, but efficient and precise structural control remains a major challenge. Herein, hollow porous bowl-like hard-soft carbon hybrid materials (BHSCs) are facilely synthesized by an in situ hard-template strategy. It is found that the outer and inner walls of the hard carbon bowls are uniformly wrapped by graphene-like soft carbon, which accelerates electron transport and promotes the insertion of potassium ions. Finite element simulation further reveals that the soft-hard-soft carbon shell structure releases stress during the insertion of potassium ions. As a result, BHSC anode exhibits an extraordinary rate capability (209 mAh g-1 at 10 A g-1 ) and excellent cycle stability with a capacity of 208 mAh g-1 after 5000 cycles at 2 A g-1 . Impressively, the as-assembled potassium-ion hybrid capacitor based on BHSC anode delivers a great energy/power density (116 Wh kg-1 /12980 W kg-1 ) and outstanding capacity retention of 83% after 8000 cycles. This work provides guidance for rational structural design of hard-soft carbon hybrid materials to improve their potassium-ion storage performance.

10.
Nanoscale ; 15(48): 19629-19637, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38018883

RESUMEN

Growing energy and environmental challenges have imposed higher requirements for the development of novel multifunctional energy storage and energy-saving devices. Electrochromic devices having similar configurations and working mechanisms with secondary batteries exhibit promising applications in dual-functional electrochromic-energy storage (ECES) devices. Electrochromic Prussian blue (PB) as typical battery cathodes are of great interest for ECES devices although they suffer from poor stability and limited capacity. In this study, a transparent metal oxide (NiO nanosheets) interlayer was incorporated to enhance the structural stability and capacity of PB while offering enlarged optical modulation (ΔT) and accelerated switching kinetics in the NiO/PB film. Impressively, the NiO/PB nanocomposite film exhibited a high areal capacity of 50 mA h m-2 and excellent electrochemical stability, simultaneously manifesting a large ΔT (73.2% at 632.8 nm), fast switching time (tc = 1.4 s, tb = 2.6 s) and higher coloration efficiency (CE = 54.9 cm2 C-1), surpassing those of the bare PB film (ΔT = 69.1% at 632.8 nm, tc = 1.6 s, tb = 4.1 s, CE = 50.9 cm2 C-1). Finally, a prototype zinc anode-based electrochromic device assembled with NiO/PB nanocomposite film exhibited a self-bleaching function and ΔT retention of up to 92% after 1000 cycles, and a 100 cm2 large area device was also demonstrated for high performance. Such a transparent metal oxide interlayer has enabled the construction of durable and fast-switching dual-functional zinc anode-based electrochromic devices and will inspire more efforts in designing novel multifunctional ECES devices.

11.
J Colloid Interface Sci ; 652(Pt A): 590-598, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37611468

RESUMEN

Zinc ion hybrid capacitors (ZIHCs) are encouraging energy storage devices for large-scale applications. Nevertheless, the electrochemical performance of ZIHCs is often limited by the cathode materials which show low energy density and rate capability practically. One of the efficient strategies to overcome these challenges is the development of advanced carbon cathode materials with abundant physi/chemisorption sites. Herein, we develop a sulfate template strategy to prepare sulfur and oxygen doped carbon nanosheets (SOCNs) as a potential cathode active material for ZIHCs. The as-prepared SOCNs exhibit porous architectures with a large surface area of 1877 m2 g-1, substantial structural defects, and high heteroatom-doped contents (O: 7.9 at%, S: 0.7 at%). These exceptional features are vital to enhancing Zn ion storage. Consequently, the SOCN cathode shows a high capacity of 151 mAh g-1 at 0.1 A g-1, high cycle stability with 83% capacity retention at 5 A g-1 after 4000 cycles, and a superior energy density of 103.1 Wh kg-1. We also investigate the dynamic adsorption/desorption behaviors of Zn ions and anions of the ZIHCs carbon electrodes during the process of charge and discharge by ex-situ experiments. This work highlights the significance of the integration with a large specific surface area and bountiful heteroatoms in carbon electrodes for achieving high-performance ZIHCs.

12.
Small Methods ; 7(11): e2300714, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37541666

RESUMEN

Porous carbon is the most promising cathode material for Zn-ion hybrid capacitors (ZIHCs), but is limited by insufficient active adsorption sites and slow ion diffusion kinetics during charge storage. Herein, a pore construction-pore expansion strategy for synthesizing multi-channel hollow carbon nanofibers (MCHCNF) is proposed, in which the sacrificial template-induced multi-channel structure eliminates the diffusion barrier for enhancing ion diffusion kinetics, and the generated ultrahigh surface area and high-density defective structures effectively increase the quantity of active sites for charge storage. Additionally, a graphene-like shell structure formed on the carbon nanofiber surface facilitates fast electron transport, and the highly matchable pore size of MCHCNF with electrolyte-ions favors the accommodation of charge carriers. These advantages lead to the optimized ZIHCs exhibit high capacity (191.4 mAh g-1 ), high energy (133.1 Wh kg-1 ), along with outstanding cycling stability (93.0% capacity retention over 15000 cycles). Systematic ex situ characterizations reveal that the dual-adsorption of anions and cations synergistically ensures the outstanding electrochemical performance, highlighting the importance of the highly-developed porous structure of MCHCNF. This work not only provides a promising strategy for improving the capacitive capability of porous materials but also sheds light on charge storage mechanisms and rational design for advanced energy storage devices.

13.
Sci Bull (Beijing) ; 68(18): 2042-2053, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37574374

RESUMEN

Breakthrough in developing cost-effective Fe-based catalysts with superior oxygen reduction reaction (ORR) activities and ultra-long-term stability for application in Zn-air batteries (ZABs) remain a priority but still full of challenges. Herein, the neighboring NiN4 single-metal-atom and Fe2N5 dual-metal-atoms on the N-doped hollow carbon sphere (Fe/Ni-NHCS) were deliberately constructed as the efficient and robust ORR catalyst for ZABs. Both theory calculations and magnetic measurements demonstrate that the introduction of NiN4 provides a significant role on optimizing the electron spin state of Fe2N5 sites and reducing the energy barrier for the adsorption and conversion of the oxygen-containing intermediates, enabling the Fe/Ni-NHCS with excellent ORR performance and ultralow byproduct HO2- yield (0.5%). Impressively, the ZABs driven by Fe/Ni-NHCS exhibit unprecedented long-term rechargeable stability over 1200 h. This work paves a new venue to manipulate the spin state of active sites for simultaneously achieving superior catalytic activities and ultra-long-term stability in energy conversion technologies.

14.
J Colloid Interface Sci ; 647: 296-305, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37262992

RESUMEN

Constructing carbon electrodes with abundant heteroatoms and appropriate graphitic interlayer spacing remains a major challenge for achieving high gravimetric and volumetric potassium storage capacities with fast kinetics. Herein, we constructed 3D graphene-like N, F dual-doped carbon sheets induced by Ni template (N, F-CNS-Ni) with dense structure and rich active sites, providing a promising approach to address the facing obstacles. Highly reversible K-ion insertion/extraction is realized in the graphitic carbon structure, and K-adsorption capability is enhanced by introducing N/F heteroatoms. As a result, the N, F-CNS-Ni electrode exhibits ultrahigh gravimetric and volumetric capacities of 404.5 mA h g-1 and 281.3 mA h cm-3 at 0.05 A/g, respectively, and a superb capacity of 259.3 mA h g-1 with a capacity retention ratio of 90 % even after 600 cycles at 5 A/g. This work presents a simple Ni-based template method to prepare graphene-like carbon nanosheets with high packing density and rich heteroatoms, and offers mechanism insight for achieving superior K-ion storage.

15.
Comput Biol Med ; 158: 106832, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37037148

RESUMEN

BACKGROUND AND OBJECTIVE: The molecular dynamics (MD) simulation is a powerful tool for researching how cancer patients are treated. The efficiency of many factors may be predicted using this approach in great detail and with atomic accuracy. METHODS: The MD simulation method was used to investigate the impact of porosity and the number of cancer cells on the atomic behavior of cancer cells during the hematogenous spread. In order to examine the stability of simulated structures, temperature and potential energy (PE) values are used. To evaluate how cell structure has changed, physical parameters such as gyration radius, interaction force, and interaction energy are also used. RESULTS: The findings demonstrate that the samples' gyration radius, interaction energy, and interaction force rose from 41.33 Å, -551.38 kcal/mol, and -207.10 kcal/mol Å to 49.49, -535.94 kcal/mol, and -190.05 kcal/mol Å, respectively, when the porosity grew from 0% to 5%. Also, the interaction energy and force in the samples fell from -551.38 kcal/mol and -207.10 kcal/mol to -588.03 kcal/mol and -237.81 kcal/mol Å, and the amount of gyration radius reduced from 41.33 to 37.14 Å as the number of cancer cells rose from 1 to 5 molecules. The strength and stability of the simulated samples will improve when the radius of gyration is decreased. CONCLUSIONS: Therefore, high accumulation of cancer cells will make them resistant to atomic collapse. It is expected that the results of this simulation should be used to optimize cancer treatment processes further.


Asunto(s)
Simulación de Dinámica Molecular , Neoplasias , Humanos , Porosidad , Simulación del Acoplamiento Molecular
16.
Heliyon ; 9(4): e14897, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37095946

RESUMEN

Background and aims: Adolescents, who are undergoing brain changes, are vulnerable to many online risks in their use or overuse of digital technology. Parental media mediation (a set of practices parents use to guide children's media use and to reduce potential negative consequences of children from media) is considered an important way to help regulate and reduce adolescents' use or problematic use of digital media and protect them from online risks. However, previous studies have shown controversial results. These controversial results reflect a reproducibility crisis in psychological science due to selective reporting, selective analysis, and inadequate description of the conditions necessary to obtain results. Methods: To address this issue and reveal the authentic effect of parental media mediation strategies, this study presented the results of a specification curve analysis of 1176 combinations indicating the longitudinal effect of parental media mediation on adolescent smartphone use or problematic use. A total of 2154 parent-adolescent dyads (adolescents' ages ranged from 9 to 18, the average age was 12.13 ± 2.20, and 817 of the adolescents were male) participated in two waves of measurements. Results: The results showed that of the 12 parental media mediations, joint parental use for learning had the greatest effect in reducing future smartphone use or problematic use among adolescents. Overall, none of the parental media mediations had a substantial effect in reducing future smartphone use or problematic use among adolescents. Discussion and conclusions: The ineffectiveness of parental media mediation poses a challenge for researchers, the public, and policy-makers. More exploration is needed in the search of effective parental media mediations for adolescents.

17.
ACS Appl Mater Interfaces ; 14(40): 45364-45372, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36166856

RESUMEN

Potassium-metal batteries (PMBs) are attractive candidates for low-cost and large-scale energy storage systems due to the abundance of potassium. However, its application is hampered by large volume change and serious dendrite growth. Herein, a CoZn semicoherent structure nanoparticle-embedded nitrogen-doped hollow carbon tube (CoZn@HCT) electrode is prepared via coaxial electrospinning. Due to the high potassiophilic CoZn semicoherent structure nanoparticles and large potassium metal storage space, the free-standing CoZn@HCT host for K metal exhibits uniform K nucleation and stable plating/stripping (stable cycling 1000 h at 1 mA cm-2 with 1 mA h cm-2). Furthermore, enhanced electrochemical performance with good cycling stability and rate capability is achieved in (CoZn@HCT@K||PTCDA) full batteries. Our results highlight a promising strategy for dendrite-free K metal anodes and high-performance PMBs.

18.
Front Psychiatry ; 13: 959103, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36147993

RESUMEN

Aims: Previous research determined the core symptoms (loss of control and being caught in the loop) of problematic smartphone use (PSU), which are of great importance to understand the structure and potential intervention targets of PSU. However, the cross-sectional design fails to reveal causality between symptoms and usually conflates the between- and within-subjects effects of PSU symptoms. This study aims to determine whether the core symptoms of PSU, indeed, dominate the future development of PSU symptoms from longitudinal between- and within-subjects levels. Materials and methods: In this study, 2191 adolescents were surveyed for 3 years for PSU symptoms. A cross-lagged panel model (CLPM) was used to explore longitudinal between-subjects causal relationships between symptoms, and a graphic vector autoregressive model (GVAR) was used to separate the between- and within-subjects effects and detect the longitudinal effect at the within-subject level. Results: The results of CLPM indicated that the core symptoms (both loss of control and being caught in the loop) of PSU, indeed, dominate the future development of PSU symptoms at a longitudinal between-subjects level. From T1 to T2, the cross-lagged model showed that both the loss of control (out-prediction = 0.042) and being caught in the loop (out-prediction = 0.053) at T1 have the highest out-prediction over other symptoms at T2. From T2 to T3, the loss of control (out-prediction = 0.027) and being caught in the loop (out-prediction = 0.037) at T2 also have the highest out-prediction over other symptoms of PSU at T3. While, after separating the between- and within-subjects effects, only being caught in the loop at T1 played a key role in promoting the development of other PSU symptoms at T3 at the within-subjects level. The contemporaneous network showed intensive connection, while the cross-sectional between-subjects network is very sparse. Conclusion: These findings not only confirm and extend the key roles of core symptoms in the dynamic aspect of PSU symptoms and PSU itself but also suggest that interventions should consider the core symptoms of PSU, individual- and group-level effects and that individualized intervention programs are needed in future.

19.
Adv Mater ; 34(34): e2204021, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35790038

RESUMEN

Employing seawater splitting systems to generate hydrogen can be economically advantageous but still remains challenging, particularly for designing efficient and high Cl- -corrosion resistant trifunctional catalysts toward the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER). Herein, single CoNC catalysts with well-defined symmetric CoN4 sites are selected as atomic platforms for electronic structure tailoring. Density function theory reveals that P-doping into CoNC can lead to the formation of asymmetric CoN3 P1 sites with symmetry-breaking electronic structures, enabling the affinity of strong oxygen-containing intermediates, moderate H adsorption, and weak Cl- adsorption. Thus, ORR/OER/HER activities and stability are optimized simultaneously with high Cl- -corrosion resistance. The asymmetric CoN3 P1 structure based catalyst with boosted ORR/OER/HER performance endows seawater-based Zn-air batteries (S-ZABs) with superior long-term stability over 750 h and allows seawater splitting to operate continuously for 1000 h. A self-driven seawater splitting powered by S-ZABs gives ultrahigh H2 production rates of 497 µmol h-1 . This work is the first to advance the scientific understanding of the competitive adsorption mechanism between Cl- and reaction intermediates from the perspective of electronic structure, paving the way for synthesis of efficient trifunctional catalysts with high Cl- -corrosion resistance.

20.
Adv Mater ; 34(29): e2202780, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35644837

RESUMEN

Charge transport is a key process that dominates battery performance, and the microstructures of the cathode, anode, and electrolyte play a central role in guiding ion and/or electron transport inside the battery. Rational design of key battery components with varying microstructure along the charge-transport direction to realize optimal local charge-transport dynamics can compensate for reaction polarization, which accelerates electrochemical reaction kinetics. Here, the principles of charge-transport mechanisms and their decisive role in battery performance are presented, followed by a discussion of the correlation between charge-transport regulation and battery microstructure design. The design strategies of the gradient cathodes, lithium-metal anodes, and solid-state electrolytes are summarized. Future directions and perspectives of gradient design are provided at the end to enable practically accessible high-energy and high-power-density batteries.

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