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1.
Nat Commun ; 15(1): 4303, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773073

RESUMEN

Uncontrollable zinc (Zn) plating and hydrogen evolution greatly undermine Zn anode reversibility. Previous electrolyte designs focus on suppressing H2O reactivity, however, the accumulation of alkaline byproducts during battery calendar aging and cycling still deteriorates the battery performance. Here, we present a direct strategy to tackle such problems using a strong Brønsted acid, bis(trifluoromethanesulfonyl)imide (HTFSI), as the electrolyte additive. This approach reformulates battery interfacial chemistry on both electrodes, suppresses continuous corrosion reactions and promotes uniform Zn deposition. The enrichment of hydrophobic TFSI- anions at the Zn|electrolyte interface creates an H2O-deficient micro-environment, thus inhibiting Zn corrosion reactions and inducing a ZnS-rich interphase. This highly acidic electrolyte demonstrates high Zn plating/stripping Coulombic efficiency up to 99.7% at 1 mA cm-2 ( > 99.8% under higher current density and areal capacity). Additionally, Zn | |ZnV6O9 full cells exhibit a high capacity retention of 76.8% after 2000 cycles.

2.
Nat Commun ; 15(1): 2033, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448427

RESUMEN

Constraining the electrochemical reactivity of free solvent molecules is pivotal for developing high-voltage lithium metal batteries, especially for ether solvents with high Li metal compatibility but low oxidation stability ( <4.0 V vs Li+/Li). The typical high concentration electrolyte approach relies on nearly saturated Li+ coordination to ether molecules, which is confronted with severe side reactions under high voltages ( >4.4 V) and extensive exothermic reactions between Li metal and reactive anions. Herein, we propose a molecular anchoring approach to restrict the interfacial reactivity of free ether solvents in diluted electrolytes. The hydrogen-bonding interactions from the anchoring solvent effectively suppress excessive ether side reactions and enhances the stability of nickel rich cathodes at 4.7 V, despite the extremely low Li+/ether molar ratio (1:9) and the absence of typical anion-derived interphase. Furthermore, the exothermic processes under thermal abuse conditions are mitigated due to the reduced reactivity of anions, which effectively postpones the battery thermal runaway.

3.
Chem Sci ; 15(12): 4238-4274, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38516064

RESUMEN

In response to societal developments and the growing demand for high-energy-density battery systems, alkali metal batteries (AMBs) have emerged as promising candidates for next-generation energy storage. Despite their high theoretical specific capacity and output voltage, AMBs face critical challenges related to high reactivity with electrolytes and unstable interphases. This review, from the perspective of electrolytes, analyzes AMB failure mechanisms, including interfacial side reactions, active materials loss, and metal dendrite growth. It then reviews recent advances in innovative electrolyte molecular designs, such as ether, ester, sulfone, sulfonamide, phosphate, and salt, aimed at overcoming the above-mentioned challenges. Finally, we propose the current molecular design principles and future promising directions that can help future precise electrolyte molecular design.

4.
ACS Appl Mater Interfaces ; 16(9): 11585-11594, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38404137

RESUMEN

The ether-based electrolytes show excellent performance on anodes in sodium-ion batteries (SIBs), but they still show poor compatibility with the cathodes. Here, ether electrolytes with NaBF4 as the main salt or additive were applied in NFM//HC full cells and showed enhanced performance than the electrolyte with NaPF6. Then, BF4- was found to have a stronger interaction with Na+, which could reduce the solvation of Na+ with the solvent, thus inducing the formation of the cathode electrolyte interface (CEI) and solid electrolyte interface (SEI) layers rich in inorganic species. Moreover, the morphology, structure, composition, and solubility of CEI and SEI were explored, concluding that NaBF4 could induce more stable CEI and SEI layers rich in B-containing species and inorganics. This work proposes using NaBF4 as the main salt or additive to improve the performance of ether electrolytes in NFM//HC full cells, which provides a strategy to improve the compatibility of ether-based electrolytes and cathodes.

5.
Ann Hematol ; 103(5): 1435-1454, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37581713

RESUMEN

Lymphomas, complex and heterogeneous malignant tumors, originate from the lymphopoietic system. These tumors are notorious for their high recurrence rates and resistance to treatment, which leads to poor prognoses. As ongoing research has shown, epigenetic modifications like DNA methylation, histone modifications, non-coding RNA regulation, and RNA modifications play crucial roles in lymphoma pathogenesis. Epigenetic modification-targeting drugs have exhibited therapeutic efficacy and tolerability in both monotherapy and combination lymphoma therapy. This review discusses pathogenic mechanisms and potential epigenetic therapeutic targets in common lymphomas, offering new avenues for lymphoma diagnosis and treatment. We also discuss the shortcomings of current lymphoma treatments, while suggesting potential areas for future research, in order to improve the prediction and prognosis of lymphoma.


Asunto(s)
Linfoma , Neoplasias , Humanos , Metilación de ADN , Epigénesis Genética , Neoplasias/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Linfoma/genética , Pronóstico
6.
Angew Chem Int Ed Engl ; 62(23): e202219310, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37016460

RESUMEN

Albeit ethers are favorable electrolyte solvents for lithium (Li) metal anode, their inferior oxidation stability (<4.0 V vs. Li/Li+ ) is problematic for high-voltage cathodes. Studies of ether electrolytes have been focusing on the archetype glyme structure with ethylene oxide moieties. Herein, we unveil the crucial effect of ion coordination configuration on oxidation stability by varying the ether backbone structure. The designed 1,3-dimethoxypropane (DMP, C3) forms a unique six-membered chelating complex with Li+ , whose stronger solvating ability suppresses oxidation side reactions. In addition, the favored hydrogen transfer reaction between C3 and anion induces a dramatic enrichment of LiF (a total atomic ratio of 76.7 %) on the cathode surface. As a result, the C3-based electrolyte enables greatly improved cycling of nickel-rich cathodes under 4.7 V. This study offers fundamental insights into rational electrolyte design for developing high-energy-density batteries.

7.
Chem Sci ; 14(5): 1184-1193, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36756331

RESUMEN

Nonflammable electrolytes are critical for the safe operation of high-voltage lithium-ion batteries (LIBs). Although organic phosphates are effective flame retardants, their poor electrochemical stability with a graphite (Gr) anode and Ni-rich cathodes would lead to the deterioration of electrode materials and fast capacity decay. Herein, we develop a safe and high-performance electrolyte formulation for high-voltage (4.6 V-class) LIBs using flame-retarding ethoxy(pentafluoro) cyclotriphosphazene (PFPN) as a non-solvating diluent for the high-concentration carbonate-ether hybrid electrolyte. In contrast to conventional nonflammable additives with restricted dosage, the high level of PFPN (69% mass ratio in our electrolyte design) could significantly increase the electrolyte flash point and protect the favored anion-rich inner solvation sheath because of its non-solvating feature, thus preventing solvent co-intercalation and structural damage to the Gr anode. The nonflammable electrolyte could also form a stable LiF-rich cathode electrolyte interphase (CEI), which enables superior electrochemical performances of Gr‖LiNi0.8Mn0.1Co0.1O2 (NMC811) full cells at high voltages (∼82.0% capacity retention after 1000 cycles at 4.5 V; 89.8% after 300 cycles at 4.6 V) and high temperatures (50 °C). This work sheds light on the electrolyte design and interphase engineering for developing practical safe high-energy-density LIBs.

8.
Angew Chem Int Ed Engl ; 62(9): e202217671, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36592001

RESUMEN

Electrolyte freezing under low temperatures is a critical challenge for the development of aqueous batteries (ABs). While lowering the freezing point of the electrolyte has caught major research efforts, limited attention has been paid to the structural evolution during the electrolyte freezing process and regulating the frozen electrolyte structure for low temperature ABs. Here, we reveal the formation process of interconnected liquid regions for ion transport in frozen electrolytes with various in situ variable-temperature technologies. More importantly, the low-temperature performance of ABs was significantly improved with the colloidal electrolyte design using graphene oxide quantum dots (GOQDs), which effectively inhibits the growth of ice crystals and expands the interconnected liquid regions for facial ion transport. This work provides new insights and a promising strategy for the electrolyte design of low-temperature ABs.

9.
Opt Lett ; 47(7): 1610-1613, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35363690

RESUMEN

Silicon-based integrated optoelectronics has become a hotspot in the field of computers and information processing systems. An integrated coherent light source on-chip with a small footprint and high efficiency is one of the most important unresolved devices. Here, we realize a silicon-based vertical cavity surface-emitting laser in the near-infrared communication band by making efforts in both controlled preparation of high-gain erbium silicate materials and novel design of high optical feedback microcavity. Single-crystal erbium/ytterbium silicate microplates with erbium concentration as high as 5 × 1021 cm-3 are controlled prepared by a chemical vapor deposition method. They can produce strong luminescence with quite a long lifetime (2.3 ms) at the wavelength of 1.5 µm. By embedding the erbium silicate microplates between two dielectric Bragg reflectors, we construct a vertical cavity surface-emitting laser at 1.5 µm, with a lasing threshold as low as 20 µJ/cm2 and Q factor of nearly 2000. Our study provides a new pathway to achieve a sub-micrometer coherent light source for optical communication.

10.
RSC Adv ; 12(8): 4939-4945, 2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35425495

RESUMEN

Flexible optoelectronic devices have numerous applications in personal wearable devices, bionic detectors, and other systems. There is an urgent need for functional materials with appealing electrical and optoelectronic properties, stretchable electrodes with outstanding mechanical flexibility, and gate medium with flexibility and low power consumption. Two-dimensional transition metal dichalcogenides (TMDCs), a novel kind of widely studied optoelectrical material, have good flexibility for their ultrathin nature. P(VDF-TrFE) is a kind of organic material with good flexibility which has been proved to be a well-performing ferroelectric gate material for photodetectors. Herein, we directly fabricated a well-performing photodetector based on ReS2 and P(VDF-TrFE) on a flexible substrate. The device achieved a high responsivity of 11.3 A W-1 and a high detectivity of 1.7 × 1010 Jones from visible to near-infrared. Moreover, with strain modulation, the device's responsivity improved 2.6 times, while the detectivity improved 1.8 times. This research provides a prospect of flexible photodetectors in the near-infrared wavelength.

11.
Sensors (Basel) ; 22(2)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35062451

RESUMEN

It is challenging to obtain wafer-scaled aligned films for completely exploiting the promising properties of semiconducting single-walled carbon nanotubes (s-SWCNTs). Aligned s-SWCNTs with a large area can be obtained by combining water evaporation and slow withdrawal-induced self-assembly in a dip-coating process. Moreover, the tunability of deposition morphology parameters such as stripe width and spacing is examined. The polarized Raman results show that s-SWCNTs can be aligned in ±8.6°. The derived two terminal photodetector shows both a high negative responsivity of 41 A/W at 520 nm and high polarization sensitivity. Our results indicate that aligned films with a large area may be useful to electronics- and optoelectronics-related applications.

12.
Appl Opt ; 61(36): 10669-10680, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36606925

RESUMEN

Deposited substances generated from hydrofluoric acid based (HF-based) etching are found to be the precursors that deteriorate the resistance of fused silica optics to laser damage. In this paper, the surface of polished fused silica was treated with a buffer oxide etchant (BOE, 5-10%wt. HF + 10%wt. N H 4 F+80-85% w t.H 2 O). The optic surface area affected by the etching-induced deposits (N H 4)S i F 6 was found to increase significantly with the amount of material removal and sensitivity to the post-cleaning procedure. Three shapes of deposited particles are simultaneously identified on the treated samples. The 3D finite-difference time-domain (FDTD) was used to simulate the light field distribution near the deposited particles, which demonstrates that fused silica is subject to more light modulation when a particle is exposed on the front surface laser than on the rear surface laser. In addition, dense particles barely increase the light intensification factor (LIF) while markedly increase the light focused probability inside fused silica. Moreover, a multiple linear regression (MLR) analysis for the LIF builds a fitting plane model of the LIF and the particle height as well as the horizontal size, revealing that the LIF increases with the size of the deposited particle, especially its height. The laser damage testing results indicate that a deposited layer of  ∼76n m in height had little influence on the laser-induced damage threshold (LIDT) of the optics and larger deposited particles with up to 9 µm thickness may deteriorate the LIDT to 41.62% that of the reference sample. Both the simulation and experimental results demonstrate that deposited particles with a height of more than 0.1 µm should be inhibited to achieve fused silica with superior laser damage performance.

13.
Small ; 17(4): e2006765, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33345467

RESUMEN

2D layered photodetectors have been widely researched for intriguing optoelectronic properties but their application fields are limited by the bandgap. Extending the detection waveband can significantly enrich functionalities and applications of photodetectors. For example, after breaking through bandgap limitation, extrinsic Si photodetectors are used for short-wavelength infrared or even long-wavelength infrared detection. Utilizing extrinsic photoconduction to extend the detection waveband of 2D layered photodetectors is attractive and desirable. However, extrinsic photoconduction has yet not been observed in 2D layered materials. Here, extrinsic photoconduction-induced short-wavelength infrared photodetectors based on Ge-based chalcogenides are reported for the first time and the effectiveness of intrinsic point defects are demonstrated. The detection waveband of room-temperature extrinsic GeSe photodetectors with the assistance of Ge vacancies is broadened to 1.6 µm. Extrinsic GeSe photodetectors have an excellent external quantum efficiency (0.5%) at the communication band of 1.31 µm and polarization-resolved capability to subwaveband radiation. Moreover, room-temperature extrinsic GeS photodetectors with a detection waveband to the communication band of 1.55 µm further verify the versatility of intrinsic point defects. This approach provides design strategies to enrich the functionalities of 2D layered photodetectors.

14.
Opt Lett ; 45(24): 6571-6574, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33325842

RESUMEN

Two-dimensional (2D) semiconductors of graphene, as well as transition-metal dichalcogenides, have performed strong interaction with light. Here the strong light-matter interaction between monolayer tungsten disulphide (WS2) excitons and microcavity photons at room temperature is well studied by the introduction of a gain material embedded dielectric optical microcavity structure. A Rabi splitting of about 36 meV is observed in angle-resolved reflectance spectra at room temperature, which agrees well with the theoretical results simulated by using the transfer matrix method. Since the cavity structures and 2D semiconductors can be prepared, the cavity and the gain materials, respectively, can be optimized separately in this platform. An all-dielectric Fabry-Pérot microcavity provides a simple but effective way to study the room temperature strong coupling between cavity photons and 2D excitons.

15.
Small ; 16(22): e2000420, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32350995

RESUMEN

MoS2 , one of the most valued 2D materials beyond graphene, shows potential for future applications in postsilicon digital electronics and optoelectronics. However, achieving hole transport in MoS2 , which is dominated by electron transport, is always a challenge. Here, MoS2 transistors gated by electrolyte gel exhibit the characteristics of hole and electron transport, a high on/off ratio over 105 , and a low subthreshold swing below 50 mV per decade. Due to the electrolyte gel, the density of electrons and holes in the MoS2 channel reaches ≈9 × 1013 and 8.85 × 1013 cm-2 , respectively. The electrolyte gel-assisted MoS2 phototransistor exhibits adjustable positive and negative photoconductive effects. Additionally, the MoS2 p-n homojunction diode affected by electrolyte gel shows high performance and a rectification ratio over 107 . These results demonstrate that modifying the conductance of MoS2 through electrolyte gel has great potential in highly integrated electronics and optoelectronic photodetectors.

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