Journal of Materials Chemistry A
·
2015
·Vol. 4
·期 6
·2089-2095
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IF 7.443
Yakun Tang,Lang Liu,Hongyang Zhao,Dianzeng Jia,Wei Liu
Porous CNT@Li4Ti5O12 core–sheath coaxial nanocables were designed using a sol–gel method combined with a following low temperature reflux process and a short post-annealing in the presence of bamboo-like polymer nanotubes acting as a template and a carbon source. As anodes for lithium ion batteries, coaxial nanocables exhibit a high reversible capacity of 322.5 mA h g−1 at 200 mA g−1 after 200 cycles. They also have excellent rate capability and superior long-term cycling stability at high current density, which could attain a high discharge capacity of 198.7 mA h g−1 at 2000 mA g−1 for up to 2000 cycles. Compared with the Li4Ti5O12 nanoparticles, the enhanced electrochemical performance of the CNT@Li4Ti5O12 nanocomposites benefits from the shortened Li+ diffusion distance, large contact surface area, high conductivity, and good structure stability of the coaxial nanocables, which simultaneously solves the major problems on the loss of electrical contact and the aggregation of particles for Li4Ti5O12 anodes. The material with a nanocable structure is a potential candidate for developing advanced electrochemical energy storage systems with high power and long life.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Nazir Ahmad,Nisar Muhammad,Hong Chen,Ji Wang,Chaohui Wei,Majid Khan,Ruizhi Yang
Developing improved anode materials is critical to the performance enhancement and the lifespan prolonging of sodium-ion batteries (SIBs). In this context, carbon-based nanostructures have emerged as a promising candidate. In this work, we have synthesized N, B, and P tri-doped carbon (NBPC) spheres using a one-step carbonization method. The as-prepared NBPC exhibits exceptional properties, including an expanded layer space, sufficient structural defects, and enhanced electrical conductivity . These characteristics synergistically contribute to the remarkable rate capability and ultra-long lifespan when NBPC is employed as an anode material for SIBs. The as-prepared NBPC demonstrates a reversible capacity of 290.6 mAh/g at 0.05 A/g, with a capacity retention of 98.4% after 800 cycles. Furthermore, NBPC exhibits an impressively ultra-long cycle life of 2400 cycles at 1.0 A/g with a reversible capacity of 140.2 mAh/g. First principle calculations confirm that the introduction of N, B, and P heteroatoms in carbon enhances the binding strength of sodium ions within NBPC. This work presents a novel approach for fabricating advanced anode materials, enabling the development of long-life SIBs for practical applications.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhiyu Ding,Qiming Tang,Yanchen Liu,Penghui Yao,Chen Liu,Xingjun Liu,Junwei Wu,Marino Lavorgna
Solid-state lithium metal batteries with higher energy density and safety are regarded as the promising next-generation energy storage devices. Porous materials hybrid with ionic liquids are becoming an important solid electrolyte due to the high ionic conductivity and enhanced interfacial compatibility. However, their poor electrochemical stability and limited Li + transport pathways remain challenged. Herein, an ionic-liquid-X zeolite hybrid is designed as the solid composite electrolyte to settle the above issues. The three-dimensional open framework of X zeolite acts as the “reservoir” of the ionic liquid providing a solid interconnected pathway to facilitate an effective lithium transmission. This transport is supported by both the TFSI − adsorption and EMIM + substitution in zeolite structure, which benefits the compatibility at electrolyte/lithium anode interface. The obtained composite electrolyte (Li-X-30) exhibits a superior ionic conductivity of 3.3 × 10 −4 S·cm −1 and a widened electrochemical window of 5.4 V. An ultralong lifespan of the assembled solid-state LiFePO 4 //metallic lithium battery is achieved with an outstanding capacity retention of 96% after 850 cycles. The designed electrolyte with ultra-long cycling stability may provide inspiration for the development of frontier solid electrolytes with potential applications in K, Na and other types of energy storage systems.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2022
·Vol. 24
·期 19
·3630-3636
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IF 3.756
Ding-Chong Han,Yu-Hui Tan,Jia-Hui Wen,Yun-Zhi Tang,Peng-Fei Wu,Yu-Kong Li,Ming-Yang Wan,Xiao-Wei Fan
Materials combining high-temperature phase transformation and fluorescence properties are not abundant, especially, stator–rotator-type inclusion compounds possessing excellent optical properties are extremely rare. In this study, a neoteric high-temperature crown ether inclusion luminophor: [(2,4,6-trifluoroanilinium)-(18-crown-6)][BF4] (1) was constructed, undergoing a reversible phase transition near Tp = 364 K. Differential thermal analysis (DTA), specific heat capacity (Cp) and differential scanning calorimetry (DSC) tests disclosed a reversible first-order phase transformation behavior of 1. Multiple-temperature PXRD analyses further demonstrated a structural transition from low- to high-symmetry. Permittivity tests for 1 exhibited a prominent step-like dielectric response near Tp, indicating that it is a promising dielectric switching material. Besides, 1 occupies a broad optical energy band of ca. 4.45 eV. The photoluminescence tests for 1 display a strong luminescence emission peak at 368 nm. Further research and computational analysis showed that the luminescence lifetime of 1 reaches up to 43.998 μs. The investigation opens up an alternative avenue to construct and synthesize phase-transition compounds possessing high-Tp and superior optical properties.
研究领域:
材料科学
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光学
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2021
·Vol. 31
·期 35
·2103978
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IF 18.808
Wenchao Wang,Xueqin Bai,Qing Ci,Lili Du,Xingang Ren,David Lee Phillips
Undesired photoelectronic dormancy through active species decay is adverse to photoactivity enhancement. An insufficient extrinsic driving force leads to ultrafast deep charge trapping and photoactive species depopulation in carbon nitride (g-C 3 N 4 ). Excitation of shallow trapping in g-C 3 N 4 with long-lived excited states opens up the possibility of pursuing high-efficiency photocatalysis. Herein, a near-field-assisted model is constructed consisting of an In 2 O 3 -cube/g-C 3 N 4 heterojunction associated with ultrafast photodynamic coupling. This In 2 O 3 -cube-induced near-field assistance system provides catalytic “hot areas”, efficiently enhances the lifetimes of excited states and shallow trapping in g-C 3 N 4 and this favors an increased active species density. Optical simulations combined with time-resolved transient absorption spectroscopy shows there is a built-in charge transfer and the active species lifetimes are longer in the In 2 O 3 -cube/g-C 3 N 4 hybrid. Besides these properties, the estimated overpotential and interfacial kinetics of the In 2 O 3 -cube/g-C 3 N 4 hybrid co-promotes the liquid phase reaction and also helps in boosting the photocatalytic performance. The photocatalytic results exhibit a tremendous improvement (34-fold) for visible-light-driven hydrogen production. Near-field-assisted long-lived active species and the influences of trap states is a novel finding for enhancing (g-C 3 N 4 )-based photocatalytic performance.
研究领域:
材料科学
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光催化
✓ 已验证
DOI
高影响因子
ChemElectroChem
·
2018
·Vol. 5
·期 22
·3498-3505
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IF 4.446
Su Nie,Li Liu,Min Li,Junfang Liu,Jing Xia,Yue Zhang,Xianyou Wang
Graphical The unique structure of these one-dimensional nanofibers with two-dimensional nanosheets on the surface is successfully synthesized. Large specific surface area can greatly shorten the diffusion routes for both electrons and ions. Besides, the carbon matrix can dramatically improve the overall conductivity. As a result, the anode exhibits excellent electrochemical capability for sodium-ion batteries. Na 2 Ti 3 O 7 /C nanofibers are successfully synthesized through an electrospinning process followed by hydrothermal treatment. The unique structure of these one-dimensional nanofibers with two-dimensional nanosheets on the surface is presumed to significantly shorten the diffusion routes for both electrons and ions. Meanwhile, the carbon matrix with a certain degree of graphitization can dramatically improve the overall conductivity. As a result, the Na 2 Ti 3 O 7 /C nanofiber electrode reveals an impressive electrochemical capability as the anode material of sodium-ion batteries. It demonstrates a reversible capacity of 110 mA h g −1 after 500 cycles at a rate of 1 C. Moreover, with almost no capacity degradation, the discharge capacity of the Na 2 Ti 3 O 7 /C nanofiber electrode remains at 58 mA h g −1 after 1500 cycles at the high rate of 50 C. This superior electrochemical performance places the Na 2 Ti 3 O 7 /C nanofibers as an anode material with great promise for sodium-ion batteries that could be applied in large-scale energy storage.
研究领域:
材料科学
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能源存储
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2020
·Vol. 8
·期 7
·1901557
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IF 8.286
Yifang Gao,Huilin Zhang,Shaomin Shuang,Chuan Dong
Visible light is ubiquitous and safer than ultraviolet light; however, synthesizing ultralong-lifetime room temperature phosphorescent (URTP) carbon dots (CDs) with visible-light excitation remains a formidable challenge. Herein, an easy and fast method for synthesizing visible-light-excited URTP CDs is devised. The synthesized CDs have URTP lifetime of 1.51 s which is a relatively long life RTP lifetime ever reported. Furthermore, it is revealed that the dense core of CDs, the formation of long-chain polymers on the surface, and the presence of hydrogen bond skeleton play a crucial role in the production of URTP. Also, the introduction of the N element is a critical factor in the URTP synthesis as it promotes the n–π* transition and facilitates intersystem crossing (ISC) such that the triplet state is filled with effective excitons. Notably, the CDs demonstrate URTP properties under the excitation of 365 UV light and exhibit URTP under the excitation of visible light. This is a rare report of visible-light-excited URTP based on CDs. Considering this excellent property, URTP CDs may be applied in the field of anticounterfeiting. These findings may broaden the path for the development of visible-light-excited URTP materials and their applications.
研究领域:
材料科学
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光学
·
化学
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2020
·
IF 16.28
Yu Long,Huan Li,Mingchun Ye,Zhengyu Chen,Zihan Wang,Ying Tao,Zhe Weng,Shi-Zhang Qiao,Quan-Hong Yang
Great progress has been made in the development of cathode materials for Al-metal batteries . However, the in-depth study of Al anodes, especially the battery instability caused by Al dendrite growth, has not received much attention. In this work, we have identified the in-situ formation of Al dendrite growth, which is proved to bottleneck the practical use of Al-metal batteries. The dendrite formation severely affects battery performance, such as voltage and efficiency fluctuations, unstable cycling, etc. To further demonstrate the detailed growing process of dendrites, we make a comprehensive investigation into the interfacial chemistry of Al anode. We have found that the naturally formed Al 2 O 3 surface film is dissolved in the ionic liquid electrolyte during Al plating, accompanied by the formation of solid-electrolyte interphase containing Al-Cl and Al-O like species on the anode surface before dendrite growth. To suppress this dendrite growth, we propose the use of porous Al, which provides a homogeneous ion flux and decreases the local current density. As a result, the porous anode maintains stable cycling over a wide range of current densities and areal capacities. The Al-graphite battery shows stable cycling up to 18000 times without capacity decay. This work suggests the significance of suppressing dendrite growth for the real applications and commercialization of Al-metal batteries and will draw attention to the battery design from the anode side .
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2018
·Vol. 9
·期 1
·1-8
·
IF 12.353
Li Qijun,Zhou Ming,Yang Mingyang,Yang Qingfeng,Zhang Zhixun,Shi Jing
Phosphorescence shows great potential for application in bioimaging and ion detection because of its long-lived luminescence and high signal-to-noise ratio, but establishing phosphorescence emission in aqueous environments remains a challenge. Herein, we present a general design strategy that effectively promotes phosphorescence by utilising water molecules to construct hydrogen-bonded networks between carbon dots (CDs) and cyanuric acid (CA). Interestingly, water molecules not only cause no phosphorescence quenching but also greatly enhance the phosphorescence emission. This enhancement behaviour can be explained by the fact that the highly ordered bound water on the CA particle surface can construct robust bridge-like hydrogen-bonded networks between the CDs and CA, which not only effectively rigidifies the C=O bonds of the CDs but also greatly enhances the rigidity of the entire system. In addition, the CD-CA suspension exhibits a high phosphorescence lifetime (687 ms) and is successfully applied in ion detection based on its visible phosphorescence.
研究领域:
材料科学
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光学材料
·
生物成像
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano-Micro Letters
·
2022
·Vol. 14
·期 1
·1-13
·
IF 23.655
Shang Wenshuo,Li Qiang,Jiang Fuyi,Huang Bingkun,Song Jisheng,Yun Shan,Liu Xuan,Kimura Hideo,Liu Jianjun,Kang Litao
Highlights
High-performance Zn||I 2 batteries were established by coating zeolite protecting layers.
The Zn 2+ -conductive layer suppresses I 3 − shuttling, Zn corrosion/dendrite growth.
The Zeolite-Zn||I 2 batteries achieve long lifespan (91.92% capacity retention after 5600 cycles), high coulombic efficiencies (99.76% in average) and large capacity (203–196 mAh g −1 at 0.2 A g −1 ) simultaneously.
Abstract The intrinsically safe Zn||I 2 battery, one of the leading candidates aiming to replace traditional Pb-acid batteries, is still seriously suffering from short shelf and cycling lifespan, due to the uncontrolled I 3 − -shuttling and dynamic parasitic reactions on Zn anodes. Considering the fact that almost all these detrimental processes terminate on the surfaces of Zn anodes, modifying Zn anodes’ surface with protecting layers should be one of the most straightforward and thorough approaches to restrain these processes. Herein, a facile zeolite-based cation-exchange protecting layer is designed to comprehensively suppress the unfavored parasitic reactions on the Zn anodes. The negatively-charged cavities in the zeolite lattice provide highly accessible migration channels for Zn 2+ , while blocking anions and electrolyte from passing through. This low-cost cation-exchange protecting layer can simultaneously suppress self-discharge, anode corrosion/passivation, and Zn dendrite growth, awarding the Zn||I 2 batteries with ultra-long cycle life (91.92% capacity retention after 5600 cycles at 2 A g −1 ), high coulombic efficiencies (99.76% in average) and large capacity (203–196 mAh g −1 at 0.2 A g −1 ). This work provides a highly affordable approach for the construction of high-performance Zn-I 2 aqueous batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
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2022
·Vol. 12
·期 18
·11477-11483
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IF 4.036
Zhaoye Lv,Jun Hou,Junjie Yao,Ye Yuan,Yulan Qian,Junyang Zhu,Hongjuan Zhao,Xiaoqing Xiong,Chengqi Jiao
Fluorescein derivatives with thermally activated delayed fluorescence (TADF) show much stronger competition ability and vaster prospects than traditional fluorescein dyes due to their prominent long lifetime. It will be of great significance to synthesize more fluorescein derivatives with TADF. In this work, compounds DCF-MPYA and FL with TADF properties were obtained by fine tuning the substituents' structure on the basis of fluorescein derivative DCF-MPYM. Their long-lived triplet excited states (21.78 μs, 32.0 μs) were proved by nanosecond time-resolved transient difference absorption spectra. The steady-state and time-resolved fluorescence spectra showed that DCF-MPYA and FL exhibited red fluorescence around 645 nm and 651 nm, respectively. The results of sensitivity to oxygen and heavy atoms further demonstrated that the time-resolved fluorescence spectra originate from the delayed fluorescence. The time correlated single-photon counting (TCSPC) data indicated that DCF-MPYA and FL showed long-lived lifetimes of 13.16 μs and 23.72 μs, respectively. The energy gap (ΔEST) between the singlet (S1) and triplet (T1) states of DCF-MPYA and FL was calculated to be 3.32 meV and 9.98 meV from the decay rate of DF as a function of temperature. The small energy gap is conducive to the occurrence of efficient TADF at room temperature. Meanwhile, Gaussian calculation was employed to observe the electron density of DCF-MPYA and FL in the ground and excited states. The calculation results indicate that the shapes and energy levels of the highest occupied molecular orbitals (HOMOs), lowest unoccupied molecular orbitals (LUMOs), and LUMOs+1 for the monoanion and dianion forms are similar and thus DCF-MPYA and FL exhibit almost the same luminescence properties. Finally, DCF-MPYA and FL with low toxicity were used in confocal and time-resolved fluorescence imaging. Our construction strategy will be beneficial for developing more fluorescein derivatives with TADF in the future.
研究领域:
化学
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生物学
·
医学成像
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 27
·12688-12696
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IF 3.3
Zhaopeng Chen,Xiumin Liang,Dan He,Min Hu,Luan Wen
Recently, room temperature phosphorescence (RTP) materials have gained widespread attention owing to their superior photophysical properties. However, it is still a challenge to realize color-tunable RTP with ultra-long lifetime in the same material through a simple strategy. Herein, we report an excitation-dependent ultra-long lifetime RTP carbon dots (CDs) composite though embedding N,O-doped CDs into an insoluble phosphate (IP) matrix (named N,O-CDs@IP). The formation of CP covalent bonds suppresses the non-radiative transition of triplet excitons and therefore activates chromogenic functional group CO. The N,O-CDs@IP composite exhibits excitation-dependent phosphorescence. When the excitation wavelength increases from 254 to 365 nm, the phosphorescence emission varies from cyan (482 nm) to green (518 nm) with ultra-long lifetimes of 2.04 s and 1.15 s, respectively. The phosphorescence quantum efficiencies at 482 and 518 nm are 24.7% and 19.88%, respectively. The excitation-dependent phosphorescence would be caused by the excitation transfer paths being different from S1 to T1 such that the energy levels are different under different excitation wavelengths in the aggregated state. Our synthesized N,O-CDs@IP can be used in fingerprint identification and anti-counterfeiting. This indicates that the N,O-CDs@IP composite has great potential in intelligent coding and advanced information encryption.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）