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1.
Angew Chem Int Ed Engl ; : e202411443, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39034634

RESUMO

The main challenges faced by aqueous rechargeable nickel-zinc batteries are their comparatively low energy density and poor cycling stability. Moreover, the preparation procedures of these cathodes are complex and not easily scalable. Herein, we utilized MXene to improve the electrodeposition preparation of NiCo layered double hydroxides (LDH). Benefiting from the improved interfacial contact between nickel foam (NF) and platting solution and the enhanced ionic conductivity of platting product based on MXene additives, the resulting binder-free NiCo LDH electrode can achieve ultrahigh areal loading (~65 mg cm-2) with abundant active surface for redox reactions and maintained short transport pathway for ion diffusion and charge transfer. Furthermore, the as-fabricated alkaline NiCo LDH-based battery delivers high discharge capacity, up to 20.2 mAh cm-2 (311 mAh g-1), accompanied by remarkable rate performance (9.6 mAh cm-2 or 148 mAh g-1 at 120 mA cm-2). Due to the high structural and chemical stability of MXenes/LDH-based electrode, excellent cycling life can also be achieved with 88.6% capacity retention after 10000 cycles. In addition, ultrahigh areal energy density (31.2 mWh cm-2) and gravimetric energy density (465 Wh kg-1) can be simultaneously achieved. This work has inspired the design of advanced cathode materials to develop high-performance aqueous zinc batteries.

2.
Angew Chem Int Ed Engl ; : e202412830, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39157915

RESUMO

In the electrochemical nitrogen reduction reaction (NRR), a leverage relationship exists between NH3-producing activity and selectivity because of the competing hydrogen evolution reaction (HER), which means that high activity with strong protons adsorption causes low product selectivity. Herein, we design a novel metal-organic hydrogen bonding framework (MOHBF) material to modulate this leverage relationship by a hydrogen-bond-regulated proton transfer pathway. The MOHBF material was composited with reduced graphene oxide (rGO) to form a Ni-N2O2 molecular catalyst (Ni-N2O2/rGO). The unique structure of O atoms in Ni-O-C and N-O-H could form hydrogen bonds with H2O molecules to interfere with protons being directly adsorbed onto Ni active sites, thus regulating the proton transfer mechanism and slowing the HER kinetics, thereby modulating the leverage relationship. Moreover, this catalyst has abundant Ni-single-atom sites enriched with Ni-N/O coordination, conducive to the adsorption and activation of N2. The Ni-N2O2/rGO exhibits simultaneously enhanced activity and selectivity of NH3 production with a maximum NH3 yield rate of 209.7 µg h-1 mgcat.-1 and a Faradaic efficiency of 45.7%, outperforming other reported single-atom NRR catalysts.

3.
J Am Chem Soc ; 145(37): 20521-20529, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37672393

RESUMO

Chalcogens, especially tellurium (Te), as conversion-type cathodes possess promising prospects for zinc batteries (ZBs) with potential rich valence supply and high energy density. However, the conversion reaction of Te is normally restricted to the Te2-/Te0 redox with a low voltage plateau at ∼0.59 V (vs Zn2+/Zn) rather than the expected positive valence conversion of Te0 to Ten+, inhibiting the development of Te-based batteries toward high output voltage and energy density. Herein, the desired reversible Te2-/Te0/Te2+/Te4+ redox behavior with up to six-electron transfer was successfully activated by employing a highly concentrated Cl--containing electrolyte (Cl- as strong nucleophile) for the first time. Three flat discharge plateaus located at 1.24, 0.77, and 0.51 V, respectively, are attained with a total capacity of 802.7 mAh g-1. Furthermore, to improve the stability of Ten+ products and enhance the cycling stability, a modified ionic liquid (IL)-based electrolyte was fabricated, leading to a high-performance Zn∥Te battery with high areal capacity (7.13 mAh cm-2), high energy density (542 Wh kgTe-1 or 227 Wh Lcathdoe+anode-1), excellent cycling performance, and a low self-discharge rate based on 400 mAh-level pouch cell. The results enhance the understanding of tellurium chemistry in batteries, substantially promising a remarkable route for advanced ZBs.

4.
Inorg Chem ; 62(15): 6138-6146, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37000131

RESUMO

Atomically precise metal nanoclusters (NCs) have emerged as feasible alternatives to traditional photosensitizers in solar energy conversion due to the unique atomic stacking mode, quantum size effect, and abundant active sites. Despite the sporadic advancement in fabricating metal NC-based photosystems, most of which are predominantly centered on Au NCs, unleashing atomically precise silver nanoclusters as light-harvesting antennas has still been in the infant stage, with the charge transfer mechanism remaining elusive. Herein, we comprehensively demonstrate the photosensitization effect of Ag NCs in the photoelectrochemical (PEC) water-splitting reaction and strictly evaluate the correlation of photosensitization efficiency with atomic architecture. To these ends, tailor-made negatively charged l-glutathione (GSH)-capped Ag NCs [Agx, Ag9(GSH)6, Ag16(GSH)9, Ag31(GSH)19] as building blocks are controllably deposited on the metal oxide (MOs = TiO2, WO3, Fe2O3) substrate by a facile self-assembly strategy. Benefiting from the highly efficient photosensitization effect of atomically precise Ag NCs, these self-assembled MOs/Ag NC heterostructured photoanodes with an elegant charge transfer interface demonstrate significantly enhanced photoelectrochemical water oxidation performances under visible-light irradiation on account of efficient charge transport from Ag NCs to the MO substrate, substantially prolonging the charge lifetime of Ag NCs. Our work would significantly inspire ongoing interest in unlocking the generic photosensitization capability of atomically precise metal NCs for solar energy conversion.

5.
Angew Chem Int Ed Engl ; 62(14): e202218745, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36705089

RESUMO

Aqueous rechargeable batteries are prospective candidates for large-scale grid energy storage. However, traditional anode materials applied lack acid-alkali co-tolerance. Herein, we report a covalent organic framework containing pyrazine (C=N) and phenylimino (-NH-) groups (HPP-COF) as a long-cycle and high-rate anode for both acidic and alkaline batteries. The HPP-COF's robust covalent linkage and the hydrogen bond network between -NH- and water molecules collectively improve the acid-alkaline co-tolerance. More importantly, the hydrogen bond network promotes the rapid transport of H+ /OH- by the Grotthuss mechanism. As a result, the HPP-COF delivers a superior capacity and cycle stability (66.6 mAh g-1 @ 30 A g-1 , over 40000 cycles in 1 M H2 SO4 electrolyte; 91.7 mAh g-1 @ 100 A g-1 , over 30000 cycles @ 30 A g-1 in 1 M NaOH electrolyte). The work opens a new direction for the structural design and application of COF materials in acidic and alkaline batteries.

6.
Chem Rec ; 22(10): e202200132, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35896955

RESUMO

Aqueous rechargeable batteries (ARBs) are considered promising electrochemical energy storage systems for grid-scale applications due to their low cost, high safety, and environmental benignity. With the demand for a wide range of application scenarios, batteries are required to work in various harsh conditions, especially the cold weather. Nevertheless, electrolytes would freeze at extremely low temperatures, resulting in dramatically sluggish kinetics and severe performance degradation. Here, we discuss the behaviors of hydrogen bonds and basic principles of anti-freezing mechanisms in aqueous electrolytes. Then, we present a systematical review of the optimization strategies of electrolytes for low-temperature aqueous batteries. Finally, the challenges and promising routes for further development of aqueous low-temperature electrolytes are provided. This review can serve as a comprehensive reference to boost the further development and practical applications of advanced ARBs operated at low temperatures.

7.
J Am Chem Soc ; 142(52): 21899-21912, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33322903

RESUMO

Conjugated polymers are deemed as conductive carrier mediators for engendering the π electrons along the molecular framework, while the role of nonconjugated insulated polymers has been generally overlooked without the capability to participate in the solar-powered oxidation-reduction kinetics and charge-transfer process. Alternatively, considering the ultrashort charge lifetime and significant deficiency of metal nanocluster (NC)-based photosystems, the fine tuning of charge migration over atomically precise ultrasmall metal NCs as novel light-harvesting antennas has so far not yet been unleashed. Here, we unlock the charge-transfer capability of a nonconjugated polymer to modulate the charge flow over metal NCs (Aux and Au25) by such a solid-state nonconductive polymer via a conceptually new chemistry strategy by which l-glutathione (GSH)-capped gold (Aux@GSH) NCs and poly(diallyl-dimethylammonium chloride) (PDDA) were alternately self-assembled on the metal oxide (MO: WO3, Fe2O3, and TiO2) substrates. The ultrathin nonconjugated PDDA interim layer periodically intercalated in-between Aux (Au25) NC layers concurrently serves as an unexpected charge-transfer mediator to foster the unidirectional electron flow from Aux(Au25) NCs to MOs by forming a tandem charge-transfer chain, hence endowing the multilayered MO/(PDDA-Aux)n heterostructures with significantly boosted photoelectrochemical water oxidation performance under light irradiation. The unanticipated role of PDDA as a cascade charge mediator is demonstrated to be universal. Our work would unlock the potential charge-transport capability of nonconjugated polymers as a novel charge mediator for solar-to-chemical conversion.

8.
Inorg Chem ; 59(10): 7325-7334, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32338507

RESUMO

Modulation of photoinduced charge separation/migration and construction of controllable charge transfer pathway over photoelectrodes have been attracting enduring interest in semiconductor-based photoelectrochemical (PEC) cells but suffer from sluggish charge transport kinetics. Here, we report a general approach to fabricate NP-TNTAs/(TMCs QDs/PSS)n (X = Te, Se, S) photoanodes via a facile and green electrostatic layer-by-layer (LbL) self-assembly strategy, for which transition-metal chalcogenides quantum dots (TMCs QDs) [CdX (X = Se, Te, S)] and poly(sodium 4-styrenesulfonate) (PSS) were periodically deposited on the nanoporous TiO2 nanotube arrays (NP-TNTAs) via substantial electrostatic force, resulting in the continuous charge transfer pathway. NP-TNTAs/(TMCs QDs/PSS)n photoanodes demonstrate significantly enhanced solar-driven photoelectrochemical (PEC) water oxidation activities, relative to NP-TNTAs and TMCs QDs under visible and simulated sunlight irradiation, predominantly because of the suitable energy level configuration between NP-TNTAs and TMCs QDs, unique integration mode, and high-speed interfacial charge separation rate endowed by LbL assembly. The ultrathin PSS intermediate layer functions as "molecule glue" for pinpoint and uniform self-assembly of TMCs QDs on the framework of NP-TNTAs and photosensitization effect of TMCs QDs triggers the unidirectional charge transfer cascade, synergistically boosting the charge separation/transfer efficiency. Our work offers an efficacious approach to craft multilayered photoelectrodes and spur further interest in finely tuning the spatial charge flow in PEC cell for solar-to-hydrogen conversion.

9.
Inorg Chem ; 59(2): 1364-1375, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31904943

RESUMO

Metal nanoparticles (NPs) have been deemed an imperative sector of nanomaterial for triggering the Schottky-junction-driven electron flow in photoredox catalysis, but they suffer from sluggish charge-transfer kinetics, rendering efficient charge flow difficult. Here, we report the construction of unidirectional charge-transfer channel in a metal/semiconductor heterostructure via a ligand-triggered self-assembly method, by which hierarchically branched ligands (DMAP)-capped Pd NPs were controllably attached on the WO3 nanorods (NRs) scaffold, resulting in the well-defined Pd@DMAP/WO3 NRs heterostructures. The pinpointed deposition of Pd@DMAP on the WO3 NRs endows the Pd@DMAP/WO3 NRs heterostructure with conspicuously improved photoactivities for organic pollutant mineralization, as well as the capacities for photocatalytic selective oxidation of aromatic alcohols to aldehydes and photoreduction of chromium ions under the irradiation of simulated sunlight and visible light, far surpassing the applicability of blank WO3 NRs. This is due to the imperative contribution of Pd@DMAP as efficient electron reservoir in accelerating the unidirectional flow of electrons from Pd@DMAP to WO3 NRs, overcoming the confinement of spatially hierarchically branched ligand and interface configuration. Moreover, interfacial charge transport efficiency is finely tuned by the interface configuration engineering. The active species in the multifarious photoreactions were unveiled, and a linker-triggered photoredox catalysis mechanism was put forward. It is hoped that our current work would afford new strategies for strategically constructing metal/semiconductor heterostructures for versatile photocatalytic applications.

10.
Inorg Chem ; 59(6): 4129-4139, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32141289

RESUMO

The capability of noble metal nanoparticles (NPs) as efficient charge transfer mediators to stimulate Schottky-junction-triggered charge flow in multifarious photocatalysis has garnered enormous attention in the past decade. Nevertheless, fine-tuning and controllable fabrication of a directional charge transport channel in metal/semiconductor heterostructures via suitable interface engineering is poorly investigated. Here, we report the progressive fabrication of a tailor-made directional charge transfer channel in Pt nanoparticles (NPs)-inlaid WO3 (Pt-WO3) nanocomposites via an efficient electrostatic layer-by-layer (LbL) self-assembly integrated with a thermal reduction treatment, by which oppositely charged metal precursor ions and polyelectrolyte building blocks were intimately and alternately assembled on the WO3 nanorods (NRs) by substantial electrostatic interaction. LbL self-assembly buildup and in situ self-etching-induced structural variation of WO3 NRs to a microsized superstructure occur simultaneously. We found that such exquisitely crafted Pt-WO3 nanocomposites exhibit conspicuously enhanced and versatile photoactivities for nonselective mineralizing of organic dye pollution and reduction of heavy metal ions at ambient conditions under both visible and simulated sunlight irradiation, demonstrating a synergistic effect. This is attributed to the imperative contribution of Pt NPs as electron traps to accelerate the directional high-efficiency electron transport from WO3 to Pt NPs, surpassing the confinement of electron transfer kinetics of WO3 owing to low conduction level. More intriguingly, photoredox catalysis can also be triggered simultaneously in the same reaction system. The primary in situ produced active species in the photocatalytic reactions were specifically analyzed, and underlying photocatalytic mechanisms were determined. Our work would provide a universal synthesis strategy for constructing various metal-decorated semiconductor nanocomposites for widespread photocatalytic utilizations.

11.
Inorg Chem ; 59(4): 2562-2574, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32013411

RESUMO

Directional and high-efficiency charge transport to the target active sites of photocatalyst is central to boost the solar energy conversion but is retarded by the sluggish charge transfer kinetics and deficiency of active sites. Here, we report the elaborate design of cascade unidirectional charge transfer channel over spatially multilayered CdS@CdTe@MoS2 dual core-shell ternary heterostructures by partial transformation of CdS to CdTe interim layer followed by seamless encapsulation with an ultrathin MoS2 layer. The suitable energy-level alignment and unique coaxial multilayered assembly mode among the building blocks accelerate the interfacial charge separation and transport, endowing the CdS@CdTe@MoS2 heterostructures with conspicuously enhanced visible-light-driven photocatalytic hydrogen generation performances along with good photostability. The integrated roles of ultrathin CdTe intermediate layer in passivating the defect sites of CdS NWs framework, mediating the unidirectional charge transfer cascade and prolonging the charge lifetime, were ascertained. Besides, the crucial role of the outermost MoS2 layer as the metal-free cocatalyst in enriching the surface active sites for hydrogen evolution was also determined. Our work would provide new alternatives for finely tuning the charge flow toward promising solar-to-hydrogen conversion efficiency.

13.
Yao Xue Xue Bao ; 49(5): 596-601, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25151727

RESUMO

This study is to investigate the protective effect of mangiferin on NF-kappaB (P65) and IkappaBalpha expression in peripheral blood mononuclear cell (PBMC) in rats with cigarette smoke induced chronic bronchitis. The rat model with chronic bronchitis was established by cigarette smoke. Real-time fluorescence RT-PCR was executed for evaluating the NF-kappaB (P65) and IKkappaBalpha gene expression in mononuclear cell, and flow cytometry for their protein expression. The serum hs-CRP (high-sensitivity C-reactive proteins) and TNF-alpha (tumor necrosis factor-alpha) were detected by enzyme-linked immunosorbent assay. The histopathological score was obtained from lung tissue HE staining slides of lung tissue. The results showed that mangiferin could markedly suppress the NF-kappaB (P65) mRNA and protein expression in mononuclear cell, while promote the IkappaBalpha mRNA and protein expression. Furthermore, mangiferin could lower serum hs-CRP and TNF-alpha level, and reduce the chronic inflammatory damage of bronchiole. These results suggested that mangiferin could notably ameliorate chronic bronchiole inflammation induced by cigarette smoke, and this protective effect might be linked to the regulation of NF-kappaB (P65) and IkappaBalpha expression in mononuclear cell.


Assuntos
Bronquite Crônica/metabolismo , Quinase I-kappa B/metabolismo , Leucócitos Mononucleares/metabolismo , Fator de Transcrição RelA/metabolismo , Xantonas/farmacologia , Animais , Brônquios/patologia , Bronquite Crônica/sangue , Bronquite Crônica/etiologia , Bronquite Crônica/patologia , Proteína C-Reativa/metabolismo , Quinase I-kappa B/genética , Leucócitos Mononucleares/patologia , Masculino , Mangifera/química , Plantas Medicinais/química , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Poluição por Fumaça de Tabaco , Fator de Transcrição RelA/genética , Fator de Necrose Tumoral alfa/sangue , Xantonas/isolamento & purificação
14.
Nat Commun ; 15(1): 3841, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714710

RESUMO

Aqueous Zn-I flow batteries utilizing low-cost porous membranes are promising candidates for high-power-density large-scale energy storage. However, capacity loss and low Coulombic efficiency resulting from polyiodide cross-over hinder the grid-level battery performance. Here, we develop colloidal chemistry for iodine-starch catholytes, endowing enlarged-sized active materials by strong chemisorption-induced colloidal aggregation. The size-sieving effect effectively suppresses polyiodide cross-over, enabling the utilization of porous membranes with high ionic conductivity. The developed flow battery achieves a high-power density of 42 mW cm-2 at 37.5 mA cm-2 with a Coulombic efficiency of over 98% and prolonged cycling for 200 cycles at 32.4 Ah L-1posolyte (50% state of charge), even at 50 °C. Furthermore, the scaled-up flow battery module integrating with photovoltaic packs demonstrates practical renewable energy storage capabilities. Cost analysis reveals a 14.3 times reduction in the installed cost due to the applicability of cheap porous membranes, indicating its potential competitiveness for grid energy storage.

15.
Adv Mater ; 36(6): e2308210, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37916840

RESUMO

As the need for sustainable battery chemistry grows, non-metallic ammonium ion (NH4 + ) batteries are receiving considerable attention because of their unique properties, such as low cost, nontoxicity, and environmental sustainability. In this study, the solvation interactions between NH4 + and solvents are elucidated and design principles for NH4 + weakly solvated electrolytes are proposed. Given that hydrogen bond interactions dominate the solvation of NH4 + and solvents, the strength of the solvent's electrostatic potential directly determines the strength of its solvating power. As a proof of concept, succinonitrile with relatively weak electronegativity is selected to construct a metal-free eutectic electrolyte (MEE). As expected, this MEE is able to significantly broaden the electrochemical stability window and reduce the solvent binding energy in the solvation shell, which leads to a lower desolvation energy barrier and a fast charge transfer process. As a result, the as-constructed NH4 -ion batteries exhibit superior reversible rate capability (energy density of 65 Wh kg-1 total active mass at 600 W kg-1 ) and unprecedent long-term cycling performance (retention of 90.2% after 1000 cycles at 1.0 A g-1 ). The proposed methodology for constructing weakly hydrogen bonded electrolytes will provide guidelines for implementing high-rate and ultra-stable NH4 + -based energy storage systems.

16.
Adv Mater ; 36(6): e2309330, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38009647

RESUMO

Chlorine-based batteries with Cl0 to Cl- redox reaction (ClRR) are promising for high-performance energystorage due to their high redox potential and large theoretical capacity. However, the inherent gas-liquid conversion feature of ClRR together with poor Cl fixation can cause Cl2 leakage, reducing battery reversibility. Herein, we utilize a Se-based organic molecule, diphenyl diselenide (di-Ph-Se), as the Cl anchoring agent and realize an atomic level-Cl fixation through chalcogen-halogencoordinating chemistry. The promoted Cl fixation, with two oxidized Cl0 anchoring on a single Ph-Se, and the multivalence conversion of Se contributeto a six-electron conversion process with up to 507 mAh g-1 and an average voltage of 1.51 V, as well as a high energy density of 665 Wh Kg-1 . Based on the superior reversibility of thedeveloped di-Ph-Se electrode with ClRR, a remarkable rate performance (205 mAh g-1 at 5 A g-1 ) and cycling performance (capacity retention of 77.3 % after 500cycles) are achieved. Significantly, the pouch cell delivers a record arealcapacity of up to 6.87 mAh cm-2 and extraordinary self-discharge performance. This chalcogen-halogen coordination chemistry between the Se electrode and Cl provides a new insight for developing reversible and efficientbatteries with halogen redox reactions.

17.
Adv Mater ; 36(30): e2402898, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38862392

RESUMO

Sulfur is a promising conversion-type cathode for zinc batteries (ZBs) due to its high discharge capacity and cost-effectiveness. However, the redox conversion of multivalent S in ZBs is still limited, only having achieved S0/S2- redox conversion with low discharge voltage and poor reversibility. This study presents significant progress by demonstrating, for the first time, the reversible S2-/S4+ redox behavior in ZBs with up to six-electron transfer (with an achieved discharge capacity of ≈1284 mAh g-1) using a highly concentrated ClO4 --containing electrolyte. The developed succinonitrile-Zn(ClO4)2 eutectic electrolyte stabilizes the positive-valence S compound and contributes to an ultra-low polarization voltage. Notably, the achieved flat discharge plateaus demonstrate the highest operation voltage (1.54 V) achieved to date in Zn‖S batteries. Furthermore, the high-voltage Zn‖S battery exhibits remarkable conversion dynamics, excellent cycling performance (85.7% capacity retention after 500 cycles), high efficiency (98.4%), and energy density (527 Wh kg S -1). This strategy of positive-valence conversion of sulfur represents a significant advancement in understanding sulfur chemistry in batteries and holds promise for future high-voltage sulfur-based batteries.

18.
Adv Mater ; 36(26): e2401924, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593988

RESUMO

With the increasing need for reliable storage systems, the conversion-type chemistry typified by bromine cathodes attracts considerable attention due to sizeable theoretical capacity, cost efficiency, and high redox potential. However, the severe loss of active species during operation remains a problem, leading researchers to resort to concentrated halide-containing electrolytes. Here, profiting from the intrinsic halide exchange in perovskite lattices, a novel low-dimensional halide hybrid perovskite cathode, TmdpPb2[IBr]6, which serves not only as a halogen reservoir for reversible three-electron conversions but also as an effective halogen absorbent by surface Pb dangling bonds, C─H…Br hydrogen bonds, and Pb─I…Br halogen bonds, is proposed. As such, the Zn||TmdpPb2[IBr]6 battery delivers three remarkable discharge voltage plateaus at 1.21 V (I0/I-), 1.47 V (I+/I0), and 1.74 V (Br0/Br-) in a typical halide-free electrolyte; meanwhile, realizing a high capacity of over 336 mAh g-1 at 0.4 A g-1 and high capacity retentions of 88% and 92% after 1000 cycles at 1.2 A g-1 and 4000 cycles at 3.2 A g-1, respectively, accompanied by a high coulombic efficiency of ≈99%. The work highlights the promising conversion-type cathodes based on metal-halide perovskite materials.

19.
Adv Mater ; 36(33): e2406451, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38888505

RESUMO

Zinc metal is recognized as the most promising anode for aqueous energy storage but suffers from severe dendrite growth and poor reversibility. However, the coulombic efficiency lacks specificity for zinc dendrite growth, particularly in Zn||Zn symmetric cells. Herein, a novel indicator (fD) based on the characteristic crystallization peaks is proposed to evaluate the growth and distribution of zinc dendrites. As a proof of concept, triethylenetetramine (TETA) is adopted as an electrolyte additive to manipulate the zinc flux for uniform deposition, with a corroborating low fD value. A highly durable zinc symmetric cell is achieved, lasting over 2500 h at 10 mA cm-2 and 400 h at a large discharge of depth (10 mA cm-2, 10 mAh cm-2). Supported by the low fD value, the Zn||TETA-ZnSO4||MnO2 batteries overcome the sudden short circuit and fast capacity fading. The study provides a feasible method to evaluate zinc dendrites and sheds light on the design of highly reversible zinc anodes.

20.
Adv Mater ; : e2410209, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39300868

RESUMO

Organic materials are promising candidates for the electrodes of aqueous zinc-ion batteries due to their nonmetallic nature, environmental friendliness, and cost-effectiveness. However, they often suffer from significant dissolution during the charge-discharge process, which poses a major hurdle to their practical applications. Inspired by membrane-less organelles in cells, a simple and versatile strategy is proposed-constructing a Janus catholyte/cathode structured electrode based on liquid-liquid phase separation, in which redox-active organic molecules are confined in the liquid state within the activated carbon, thereby eliminating the volume effect and preventing their diffusion into the electrolyte. The customization of phase separation systems by leveraging the hydrophobicity/hydrophilicity differences of various anions is successfully demonstrated. This approach allows for precise regulation of ion cluster/coordination structures, enabling the confinement of active substances while ensuring efficient ion transport. Consequently, the as-constructed Zn||Janus catholyte/cathode cells exhibit superior reversible rate capacity (186 mA h g-1 at 5.0 A g-1) and remarkable cycling performance (retention of 72.5% after 12 000 cycles). The strategy in building Janus catholyte/cathode structured electrodes breaks free from the limitations imposed by traditional solid-state electrodes, offering tremendous opportunities for exploring diverse advanced battery systems.

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