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1.
Artigo em Inglês | MEDLINE | ID: mdl-32692428

RESUMO

Organic electroactive compounds are attractive to serve as the cathode materials of aqueous zinc-ion batteries (ZIBs) because of their resource renewability, environmentally friendliness and structural diversity. Up to now, various organic electrode materials have been developed and different redox mechanisms are observed in aqueous Zn/organic battery systems. In this Minireview, we present the recent developments in the energy storage mechanisms and design of the organic electrode materials of aqueous ZIBs, including carbonyl compounds, imine compounds, conductive polymers, nitronyl nitroxides, organosulfur polymers and triphenylamine derivatives. Furthermore, we highlight the design strategies to improve their electrochemical performance in the aspects of specific capacity, output voltage, cycle life and rate capability. Finally, we discuss the challenges and future perspectives of aqueous Zn/organic batteries.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32543738

RESUMO

Smart self-protection is essential for addressing safety issues of energy-storage devices. However, conventional strategies based on sol-gel transition electrolytes often suffer from unstable self-recovery performance. Herein, smart separators based on thermal-gated poly(N-isopropylacrylamide) (PNIPAM) hydrogel electrolytes were developed for rechargeable zinc-ion batteries (ZIBs). Such PNIPAM-based separators not only display a pore structure evolution from opened to closed states, but also exhibit a surface wettability transition from hydrophilic to hydrophobic behaviors when the temperature rises. This behavior can suppress the migration of electrolyte ions across the separators, realizing the self-protection of ZIBs at high temperatures. Furthermore, the thermal-gated behavior is highly reversible, even after multiple heating/cooling cycles, because of the reversibility of temperature-dependent structural evolution and hydrophilic/hydrophobic transition. This work will pave the way for designing thermal-responsive energy-storage devices with safe and controlled energy delivery.

3.
Chem Soc Rev ; 49(13): 4203-4219, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32478772

RESUMO

Rechargeable zinc-ion batteries (ZIBs) are promising for large scale energy storage and portable electronic applications due to their low cost, material abundance, high safety, acceptable energy density and environmental friendliness. This tutorial review presents an introduction to the fundamentals, challenges, recent advances and prospects related to ZIBs. Firstly, the intrinsic chemical properties, challenges and strategies of metallic zinc anodes are underscored. Then, the multiple types of cathode materials are classified and comparatively discussed in terms of their structural and electrochemical properties, issues and remedies. Specific attention is paid to the mechanistic understanding and structural transformation of cathode materials based on Zn ion-(de)intercalation chemistry. After that, the widely investigated electrolytes are elaborated by discussing their effect on Zn plating/stripping behaviours, reaction kinetics, electrode/electrolyte interface chemistries, and cell performances. Finally, the remaining challenges and future perspectives are outlined for the development of ZIBs.

4.
ACS Nano ; 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32432458

RESUMO

Among various energy storage devices, aqueous zinc-ion batteries (ZIBs) have captured great attention due to their high safety and low cost. One of the most promising cathodes of aqueous ZIBs is layered vanadium-based compounds. However, they often suffer from the capacity decaying during cycling. Herein, we prepared KV3O8·0.75H2O (KVO) and further incorporated it into a single-walled carbon nanotube (SWCNT) network, achieving freestanding KVO/SWCNT composite films. The KVO/SWCNT cathodes exhibit a Zn2+/H+ insertion/extraction mechanism, resulting in fast kinetics of ion transfer. In addition, the KVO/SWCNT composite films possess a segregated network structure, which offers the fast kinetics of electron transfer and guarantees an intimate contact between KVO and SWCNTs during cycling. As a result, the resultant batteries deliver a high capacity of 379 mAh g-1, excellent rate capability, and an ultralong cycle life up to 10,000 cycles with a high capacity retention of 91%. In addition, owing to the high conductivity and flexibility of KVO/SWCNT films, flexible soft-packaged ZIBs based on KVO/SWCNT film cathodes were assembled and displayed stable electrochemical performance at different bending states.

5.
Small ; : e1907153, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32285595

RESUMO

Lithium-sulfur (Li-S) batteries as a promising energy storage candidate have attracted attention due to their high energy density (2600 Wh kg-1 ). However, the serious shuttle effect caused by the dissolution of the lithium polysulfides (LiPS) in electrolyte significantly degrades their cycling life and rate performance. Herein, the "binary active sites" concept in a Li-S battery system via the design of a cobalt vanadium oxide (CVO) modified multifunctional separator is designed. In the case of CVO, active vanadium sites simultaneously anchor the LiPS through the chemical affinity and active cobalt sites can dominate a rapid kinetic conversion. Such a synergistic effect contributes to improving the utilization of sulfur in the electrochemical process for the enhanced electrochemical performance. As a result, the Li-S battery with the CVO modified separator possesses a high reversible capacity of 1585.5 mAh g-1 at 0.1 C and superior cycling stability with 0.012% capacity decay cycle-1 after 3000 cycles. More impressively, the assembled soft-packaged Li-S devices can exhibit the excellent stability under bending states. This binary active sites strategy provides a route to design the functional materials for modifying separators of Li-S batteries to improve the performance.

6.
Angew Chem Int Ed Engl ; 59(29): 11800-11807, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32301196

RESUMO

The reversible capacity of AlCl4 - intercalation/de-intercalation in conventional cathodes of aluminum-ion batteries (AIBs) is difficult to improve due to the large size of AlCl4 - anions. Therefore, it is highly desirable to realize the intercalation/de-intercalation of smaller Al-based ions. Here, we fabricated polyaniline/single-walled carbon nanotubes (PANI/SWCNTs) composite films and protonated the PANI nanorods. The protonation endows PANI with more active sites and enhanced conductivity. Hyper self-protonated PANI (PANI(H+ )) exhibits reversible AlCl2 + intercalation/de-intercalation during the discharge/charge process. As a result, the discharge capacity of the Al/PANI(H+ ) battery is twice as high as that of the initial composite films. PANI(H+ )@SWCNT electrodes also have a stable cycling life with only 0.003 % capacity decay per cycle over 8000 cycles. Owing to the excellent mechanical properties, PANI(H+ )@SWCNT composite films can act as the electrodes of flexible AIBs.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31943699

RESUMO

Proton storage in rechargeable aqueous zinc-ion batteries (ZIBs) is attracting extensive attention owing to the fast kinetics of H+ insertion/extraction. However, it has not been achieved in organic materials-based ZIBs with a mild electrolyte. Now, aqueous ZIBs based on diquinoxalino [2,3-a:2',3'-c] phenazine (HATN) in a mild electrolyte are developed. Electrochemical and structural analysis confirm for the first time that such Zn-HATN batteries experience a H+ uptake/removal behavior with highly reversible structural evolution of HATN. The H+ uptake/removal endows the Zn-HATN batteries with enhanced electrochemical performance. Proton insertion chemistry will broaden the horizons of aqueous Zn-organic batteries and open up new opportunities to construct high-performance ZIBs.

8.
Chem Rev ; 120(2): 1184-1249, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31580651

RESUMO

The surface and interfaces of heterogeneous catalysts are essential to their performance as they are often considered to be active sites for catalytic reactions. With the development of nanoscience, the ability to tune surface and interface of nanostructures has provided a versatile tool for the development and optimization of a heterogeneous catalyst. In this Review, we present the surface and interface control of nanoparticle catalysts in the context of oxygen reduction reaction (ORR), electrochemical CO2 reduction reaction (CO2 RR), and tandem catalysis in three sections. In the first section, we start with the activity of ORR on the nanoscale surface and then focus on the approaches to optimize the performance of Pt-based catalyst including using alloying, core-shell structure, and high surface area open structures. In the section of CO2 RR, where the surface composition of the catalysts plays a dominant role, we cover its reaction fundamentals and the performance of different nanosized metal catalysts. For tandem catalysis, where adjacent catalytic interfaces in a single nanostructure catalyze sequential reactions, we describe its concept and principle, catalyst synthesis methodology, and application in different reactions.

9.
Chem Rev ; 120(2): 623-682, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31868347

RESUMO

The use of well-defined materials in heterogeneous catalysis will open up numerous new opportunities for the development of advanced catalysts to address the global challenges in energy and the environment. This review surveys the roles of nanoparticles and isolated single atom sites in catalytic reactions. In the second section, the effects of size, shape, and metal-support interactions are discussed for nanostructured catalysts. Case studies are summarized to illustrate the dynamics of structure evolution of well-defined nanoparticles under certain reaction conditions. In the third section, we review the syntheses and catalytic applications of isolated single atomic sites anchored on different types of supports. In the final part, we conclude by highlighting the challenges and opportunities of well-defined materials for catalyst development and gaining a fundamental understanding of their active sites.

10.
Medicine (Baltimore) ; 98(41): e17387, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31593088

RESUMO

BACKGROUND: Double-lumen bronchial tubes (DLBT) and bronchial blockers (BB) are commonly used in the anesthesia for clinical thoracic surgery. But there are few systematic clinical comparisons between them. In this study, the effects of BB and DLBT on one-lung ventilation (OLV) are studied. METHODS: The 200 patients with thoracic tuberculosis undergoing thoracic surgery, were randomly assigned to group A (DLBT) and group B (BB). Intubation time, hemodynamic changes (mean arterial pressure [MAP], heart rate [HR]), and arterial blood gas indicators (arterial partial pressure of carbon dioxide [PaCO2], arterial partial pressure of oxygen [PaO2], airway plateau pressure [Pplat], and airway peak pressure [Ppeak]) at 4 time points were recorded. Complications such as hoarseness, pulmonary infection, pharyngalgia, and surgical success rate were also evaluated postoperatively. RESULTS: Intubation times were shorter in group B. Both MAP and HR in group A were significantly higher 1 minute after intubation than before, but also higher than those in group B. PaO2 levels were lower in both groups during (OLV) than immediately after anesthesia and after two-lung ventilation (TLV), with PaO2 being lower after 60 minutes of OLV than after 20 minutes of OLV. Furthermore, at both points during OLV, PaO2 was lower in group A than in group B. No significant differences in PaCO2 were found between the 2 groups. Ppeak and Pplat were increased in both groups during OLV, with both being higher in group A than in group B. The incidence of postoperative hoarseness, pulmonary infection, and pharyngalgia were lower in group B. There was no significant difference in the success rate of operation between the 2 groups. CONCLUSIONS: Compare with using DLBT, implementation of BB in general anesthesia has less impact on hemodynamics, PaO2 and airway pressures, and achieves lower incidence of postoperative complication.


Assuntos
Anestesia Geral/métodos , Broncoconstritores/administração & dosagem , Ventilação Monopulmonar/métodos , Procedimentos Cirúrgicos Torácicos/métodos , Tuberculose Pulmonar/cirurgia , Idoso , Feminino , Hemodinâmica , Humanos , Intubação Intratraqueal , Masculino , Pessoa de Meia-Idade , Pressão Parcial
11.
Angew Chem Int Ed Engl ; 58(46): 16451-16455, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31482655

RESUMO

Alloying anodes are promising high-capacity electrode materials for K-ion batteries (KIBs). However, KIBs based on alloying anodes suffer from rapid capacity decay due to the instability of K metal and large volume expansion of alloying anodes. Herein, the effects of salts and solvents on the cycling stability of KIBs based on a typical alloying anode such as amorphous red phosphorus (RP) are investigated, and the potassium bis(fluorosulfonyl)imide (KFSI) salt-based carbonate electrolyte is versatile to achieve simultaneous stabilization of K metal and RP electrodes for highly stable KIBs. This salt-solvent complex with a moderate solvation energy can alleviate side reactions between K metal and the electrolyte and facilitate K+ ion diffusion/desolvation. Moreover, robust SEI layers that form on K metal and RP electrodes can suppress K dendrite growth and resist RP volume change. This strategy of electrolyte regulation can be applicable to other alloying anodes for high-performance KIBs.

12.
Nanoscale ; 11(38): 17630-17636, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31538168

RESUMO

The recent development of flexible and wearable electronic devices has increased the demand for energy storage devices with excellent flexibility and structural stability. Aqueous zinc-ion batteries (ZIBs) are promising energy storage devices due to their low cost, high safety, and eco-friendliness. Therefore, flexible ZIBs have to be considered. Herein, we design the flexible all-in-one ZIBs, where the reduced graphene oxide/polyaniline (rGO/PANI) cathode, cellulose nanofiber (CNF) separator, and exfoliated graphene (EG)/Zn anode are integrated together using an all-freeze-casting strategy. The continuous seamless connection of such all-in-one ZIBs can avoid displacing and detaching between the electrodes and separator under different bending states and improve the load-transfer capacity and interface strength between the neighboring component layers. As a result, the all-in-one ZIBs show excellent flexibility and superior electrochemical stability under different bending states.

13.
Adv Mater ; 31(40): e1903955, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31423664

RESUMO

Lithium-sulfur (Li-S) batteries have arousing interest because of their high theoretical energy density. However, they often suffer from sluggish conversion of lithium polysulfides (LiPS) during the charge/discharge process. Single nickel (Ni) atoms on nitrogen-doped graphene (Ni@NG) with Ni-N4 structure are prepared and introduced to modify the separators of Li-S batteries. The oxidized Ni sites of the Ni-N4 structure act as polysulfide traps, efficiently accommodating polysulfide ion electrons by forming strong Sx 2- ⋅⋅⋅NiN bonding. Additionally, charge transfer between the LiPS and oxidized Ni sites endows the LiPS on Ni@NG with low free energy and decomposition energy barrier in an electrochemical process, accelerating the kinetic conversion of LiPS during the charge/discharge process. Furthermore, the large binding energy of LiPS on Ni@NG also shows its ability to immobilize the LiPS and further suppresses the undesirable shuttle effect. Therefore, a Li-S battery based on a Ni@NG modified separator exhibits excellent rate performance and stable cycling life with only 0.06% capacity decay per cycle. It affords fresh insights for developing single-atom catalysts to accelerate the kinetic conversion of LiPS for highly stable Li-S batteries.

14.
Chemistry ; 25(64): 14480-14494, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31407398

RESUMO

Rechargeable aqueous zinc-ion batteries (ZIBs) have garnered tremendous attention in the field of next energy storage devices due to their high safety, low cost, abundant resources, and eco-friendliness. As an important component of the zinc-ion battery, the electrolyte plays a vital role in the electrochemical properties, since it will provide a pathway for the migrations of the zinc ions between the cathode and anode, and determine the ionic conductivity, electrochemically stable potential window, and reaction mechanism. In this Minireview, a brief introduction of electrochemical principles of the aqueous ZIBs is discussed and the recent advances of various aqueous electrolytes for ZIBs, including liquid, gel, and multifunctional hydrogel electrolytes are also summarized. Furthermore, the remaining challenges and future directions of electrolytes in aqueous ZIBs are also discussed, which could provide clues for the following development.

15.
Angew Chem Int Ed Engl ; 58(46): 16358-16367, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31050086

RESUMO

Aqueous zinc-ion batteries (ZIBs) are considered promising energy storage devices for large-scale energy storage systems as a consequence of their safety benefits and low cost. In recent years, various vanadium-based compounds have been widely developed to serve as the cathodes of aqueous ZIBs because of their low cost and high theoretical capacity. Furthermore, different energy storage mechanisms are observed in ZIBs based on vanadium-based cathodes. In this Minireview, we present a comprehensive overview of the energy storage mechanisms and structural features of various vanadium-based cathodes in ZIBs. Furthermore, we discuss strategies for improving the electrochemical performance of vanadium-based cathodes; including, insertion of metal ions, adjustment of structural water, selection of conductive additives, and optimization of electrolytes. Finally, this Minireview offers insight into potential future directions in the design of innovative vanadium-based electrode materials.

16.
Chem Sci ; 10(15): 4306-4312, 2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31057757

RESUMO

All-solid-state sodium batteries have great potential for large-scale energy storage applications. However, constructing a compatible Na anode/solid-state electrolyte (SSE) interface is still challenging because most SSEs are unstable toward Na metal. A succinonitrile (SN) SSE shows high room-temperature ionic conductivity (10-3 S cm-1) but easily deteriorates if in contact with Na metal, leading to continuously increased interfacial resistance. Here we present an extremely simple approach to introduce a compact NaF-rich interphase on a Na surface via chemical reactions between fluoroethylene carbonate-Na+ and Na metal, resulting in a compatible Na anode/SN-based electrolyte interface. The in situ formed NaF-rich interphase can not only prevent side reactions between the SN-based electrolyte and Na anode but also regulate the uniform deposition of dendrite-free Na. As a result, the symmetric cells show a low overpotential of 150 mV after cycling for 4000 h. Furthermore, all-solid-state Na-CO2 batteries (4Na + 3CO2 ↔ 2Na2CO3 + C) with the compatible interface can run for 50 cycles with a small overpotential increase of 0.33 V. This work provides a promising method to build a stable interface that enables the use of an SSE which is unstable toward Na in Na metal batteries.

17.
Angew Chem Int Ed Engl ; 58(21): 7062-7067, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-30893503

RESUMO

Rechargeable aqueous zinc-ion batteries (ZIBs) are promising energy-storage devices owing to their low cost and high safety. However, their energy-storage mechanisms are complex and not well established. Recent energy-storage mechanisms of ZIBs usually depend on cationic redox processes. Anionic redox processes have not been observed owing to the limitations of cathodes and electrolytes. Herein, we describe highly reversible aqueous ZIBs based on layered VOPO4 cathodes and a water-in-salt electrolyte. Such batteries display reversible oxygen redox chemistry in a high-voltage region. The oxygen redox process not only provides about 27 % additional capacity, but also increases the average operating voltage to around 1.56 V, thus increasing the energy density by approximately 36 %. Furthermore, the oxygen redox process promotes the reversible crystal-structure evolution of VOPO4 during charge/discharge processes, thus resulting in enhanced rate capability and cycling performance.

18.
Angew Chem Int Ed Engl ; 58(13): 4313-4317, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30697965

RESUMO

The self-healing of zinc-ion batteries (ZIBs) will not only significantly improve the durability and extend the lifetime of devices, but also decrease electronic waste and economic cost. A poly(vinyl alcohol)/zinc trifluoromethanesulfonate (PVA/Zn(CF3 SO3 )2 ) hydrogel electrolyte was fabricated by a facile freeze/thaw strategy. PVA/Zn(CF3 SO3 )2 hydrogels possess excellent ionic conductivity and stable electrochemical performance. Such hydrogel electrolytes can autonomously self-heal by hydrogen bonding without any external stimulus. All-in-one integrated ZIBs can be assembled by incorporating the cathode, separator, and anode into hydrogel matrix since the fabrication of PVA/Zn(CF3 SO3 )2 hydrogel is a process of converting the liquid to quasi-solid state. The ZIBs show an outstanding self-healing and can recover electrochemical performance completely even after several cutting/healing cycles.

19.
ACS Nano ; 12(12): 12503-12511, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30507142

RESUMO

The recent boom in flexible and wearable electronic devices has increased the demand for flexible energy storage devices. The flexible lithium-sulfur (Li-S) battery is considered to be a promising candidate due to its high energy density and low cost. Herein, a flexible Li-S battery was fabricated based on an all-in-one integrated configuration, where a multiwalled carbon nanotubes/sulfur (MWCNTs/S) cathode, MWCNTs/manganese dioxide (MnO2) interlayer, polypropylene (PP) separator, and Li anode were integrated together by combining blade coating with vacuum evaporation methods. Each component of the all-in-one structure can be seamlessly connected with the neighboring layers. Such an optimal interfacial connection can effectively enhance electron- and/or load-transfer capacity by avoiding the relative displacement or detachment between two neighboring components at bending strain. Therefore, the flexible all-in-one Li-S batteries display fast electrochemical kinetics and have stable electrochemical performance under different bending states.

20.
ACS Nano ; 12(9): 9578-9586, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30199634

RESUMO

Lithium-sulfur (Li-S) batteries are strongly considered as promising energy storage devices due to their high capacity and large theoretical energy density. However, the shuttle of polysulfides and their sluggish kinetic conversion in electrochemical processes seriously reduce the utilization of active sulfur, leading to a rapid capacity fading. Herein we introduced indium nitride (InN) nanowires into Li-S batteries through separator modification. Both the indium cation and electron-rich nitrogen atom of InN served as the polysulfide traps through strong chemical affinity. Meanwhile, the rapid electron transfer on the surface of InN accelerated the conversion of polysulfides in a working battery. The bifunction of InN nanowires effectively suppressed the shuttle effect. Therefore, Li-S batteries with InN-modified separators exhibit excellent rate performance and high stable cycling life with only 0.015% capacity decay per cycle after 1000 cycles, which affords fresh insights into the energy chemistry of high-stable Li-S batteries.

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