ELECTROCHIMICA ACTA
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2022
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IF 7.336
Wenjie Zhao,Weigang Wang,Guorong Hu,Ke Du,Zhongdong Peng,Xudong Zhang,Huan Li,Zijun Fang,Yanbing Cao
Porous Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) with micro-nano structure was prepared by a simple deep-eutectic solvent method with good crystallinity and uniformity. Surface modification was used to produce carbon-coated NVPF (NVPF/C). The unique morphologic architecture and surface modification improve the structural stability and interfacial chemical stability of NVPF, ensuring the excellent rate performance and cycle stability of NVPF/C. At 120 °C, secondary microspheres NVPF composed of nanoparticles are successfully synthesized. By liquid phase reaction in a deep-eutectic solvent X-ray diffraction analysis reveals that these microspheres have good crystallinity . The NVPF/C with an amorphous fluorocarbon coating layer is constructed by pyrolysis of polytetrafluoroethylene (PTFE). The mesoporous structure and the existence of the coating layer are clearly obvious under the high-definition transmission electron microscope. The amorphous fluorocarbon layer enhances the reversibility and transmission ability of Na + , improving the electrochemical kinetics. And the obtained NVPF/C cathode material displays high-rate performance. The as-prepared NVPF/C-F composites with 6 %wt coating of PTFE have a specific capacity of 110.6 mAh g −1 at 10 C, 106.4 mAh g −1 at 20 C and 94.6 mAh g −1 at 50 C. The capacity retention rate is 90.4 % after 700 cycles at 20 C. This research provides a facile and inexpensive approach for getting high-rate performance sodium-ion battery cathode materials.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2023
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IF 9.2
Haiyan He,Kuo Cao,Shu Guo,Wenjiao Yao,Fei Chen,Jiemin dong,Chun-Hua Chen
Potassium-ion batteries (KIBs) have attracted more and more attention due to the abundant potassium resources and hence low cost of raw materials. Nevertheless, the performances of KIBs are still unsatisfactory for practical applications, mainly due to the lack of suitable cathode materials . In this work, we report for the first time a novel polyanionic compound K 1+δ VOPO 4 F as a potassium ion storage host. Thanks to its flexible while stable layered [VOPO 4 F] ∞ framework, as a KIB cathode material, it can provide a reversible capacity of about 101 mAh g −1 at a rate of 0.2 C with a 87% capacity retention after 250 cycles. The corresponding energy density of 363 Wh kg −1 is among the highest for K-ion storage. The working mechanism of the V 4+ /V 5+ redox reaction is determined by in-situ X-ray diffraction (XRD) and ex situ X-ray photoelectron spectra (XPS) analyses. Notably, it delivers a stable average capacity of 75 mAh g −1 for 700 cycles at 1 C with a capacity retention rate of 76%. This work presents that K 1+δ VOPO 4 F is a promising K + storage cathode material with merits of high energy density and long cyclability.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
Chemical Engineering Journal Advances
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2023
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IF 0
Zheng Lian,Bao Zhang,Yannan Zhang,Xiaohua Yu,Zhengwu Wang,Yixue Huang,Jianguo Duan,Ding Wang,Xiaoyuan Zeng,Peng Dong,Yingjie Zhang
LiNi 0.5 Mn 1.5 O 4 has been thoroughly investigated as one of the most promising high-voltage positive materials for Li-ion batteries, owing to its low cost, high energy density and good stability. Nonetheless, the limited reversible capacity and poor cycle efficiency limit its use to the high-end digital domain. Herein, the SmF 3 cathode electrolyte interphase modified strategy has been first explored for LiNi 0.5 Mn 1.5 O 4 , which demonstrated outstanding electrochemical performance. The surface regulated sample demonstrates a preferred initial discharge-specific capacity of 137.85 mAh g −1 at a 1 C rate and sustains a discharge capacity of 110.21 mAh g −1 after 200 cycles. More importantly, SmF 3 can successfully reduce the occurrence of adverse reactions while producing a thin and homogenous CEI layer. The basic understanding of cathode electrolyte interphase alteration on surface morphology, crystal structure, and chemical components of the modified samples are revealed through means of various testing methods. The surface modification with SmF 3 can effectively mitigate the formation of generated by-products and enhance the transport of Li + . This technique of modifying the cathode electrolyte interphase with SmF 3 serves as a starting point for further research into the performance degradation process and opens up a new avenue for improving the electrochemical performance of the spinel positive materials.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Wenxu Wang,Yue Sun,Pengcong Wen,Yueqiang Zhou,Dongyun Zhang,Chengkang Chang
This study presents a novel modification strategy involving the replacement of Mn with Sc in the cathode of NaNi 1/3 Fe 1/3 Mn 1/3 O 2 (NFM). The results of this study confirmed that Sc doping introduced strong Sc–O bonds to enhance the bonding between transition metal ions and O 2− . Additionally, Sc doping reduced the proportion Mn 3+ in the material (from 50.23% to 47.46%), thereby inhibiting the material structural distortion due to the Jahn–Teller effect induced by Mn 3+ . These factors were the main contributors to the improved cycling performance of the modified material. Furthermore, the introduction of Sc decreased the band gap of the material (1.7416–1.6706 eV) and the Na + activation barrier energy (0.773–0.732 eV). These changes not noly facilitated the de-embedding of Na + in the material lattice but also significantly enhanced the material electronic conductivity, leading to an excellent rate performance of the modified material. These results indicate that the NFM-Sc0.01 sample maintained an ultra-high capacity retention of 86.45% after 200 cycles at 1 C. At 5 C, the discharge capacity of NFM-Sc0.01 significantly increased from 79.3 mAh g −1 in NFM to 93.4 mAh g −1 , demonstrating great potential for industrialized applications.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Yongshun Liang,Lang Xu,Ya Li,Jie Ding,Yiyao Li,Kaijiao Duan,Wei Bai,Junming Guo,Mingwu Xiang
Layered Ni-rich oxides LiNi x Co y Mn 1-x-y O 2 (x ≥ 0.6, x + y = 1) are considered the best promising cathode material for high-performance lithium-ion secondary batteries. However, the time-consuming and complicated preparation process of spherical precursors greatly increases the consumption of energy and time, whilst suffering the challenges of liquid waste and Li uniform distribution. Herein, a simple microwave liquid phase flameless combustion method with the advantages of time-saving and energy-conservation has been proposed to synthesize Ni-rich LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM 622 ). The NCM 622 powders with uniform element distribution are obtained by heating the liquid mixture of raw materials in a simple domestic microwave oven only for 5 minutes and without waste liquid production. Subsequently, the microwave-synthesized NCM 622 powders are further calcined in high-temperature with different temperatures and time in order to obtain the final products with high crystallinity and good electrochemical performances. As a result, the optimal NCM 622 cathode material calcined at 800 °C for 14 h exhibits excellent irregular polyhedral morphology and low degree of Li + /Ni + mixing, whilst displays high first discharge capacity of 179.1 mAh g −1 and 204.9 mAh g −1 with the capacity retention of 88.21 % and 81.36 % (100 cycles) in 3–4.3 V and 3–4.5 V (0.2 C), respectively.
研究领域:
材料科学
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能源技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Meiting Huang,Haoxuan Yu,Liang Chen,Haitao Yang,Zhihao Wang,Yifeng Li,Kechun Chen,Chenxi Xu,Liming Yang,Xubiao Luo
To face the large–scale retirement of lithium–ion batteries (LIBs), direct regeneration of spent NCM622 (LiNi 0.6 Co 0.2 Mn 0.2 O 2 ) cathode can effectively alleviate the current resource and environmental pressures. During the recycling process, the binder polyvinylidene fluoride (PVDF) inevitably becomes an inherent impurity in the active material. Whether the inherent impurity can assist the regeneration of spent NCM or not is becoming a focus of attentions. Hereby, a closed–loop direct regeneration strategy that transforms the inherent PVDF impurity into a F dopant is proposed, and a LiNO 3 –LiOH eutectic molten system is utilized to repair the elemental loss and structural defects in highly degraded NCM622 cathode while achieving F doping. It is found that the fluorine element is uniformly doped into both the surface and bulk phases of the whole material. The F–containing regenerated NCM cathode (R–NCM622–F) shows a stable layered structure with markedly suppressed lattice oxygen escape, as substantiated by the experimental analysis and theoretical calculation. As a result, the obtained R–NCM622–F exhibits a satisfactory repaired specific capacity of 169.6 mAh g −1 and excellent cycling stability, which retains 85.8 % of its initial capacity after 200 cycles. Meanwhile, it can deliver a considerable capacity of 120mAh g −1 even at a high rate of 5C. Clearly, our regeneration strategy obviates the necessity for intricate pretreatments, and instead employs the inherent PVDF impurity to achieve the direct regeneration process, thereby offering a promising avenue to the large–scale direct regeneration of layered cathodes.
研究领域:
材料科学
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环境科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Wei Wei,Tao Ye,Zunqiu Xiao,Kejia Xiang,Huaying Wang,Zhongtai Zhang,Shitong Wang,Zilong Tang
The development of cathode materials has always been one of the most crucial areas of research in the field of sodium-ion batteries. Sulfate-based polyanionic materials, known for their high working voltage characteristics, have received widespread attention. In this work, a fluoro-sulfate sodium-ion battery cathode material, Na3Fe2(SO4)3F modified with carbon nanotubes, was developed using a low-temperature solid-state annealing method. This Na3Fe2(SO4)3F cathode exhibits an exceptionally high voltage of 3.77 V, excellent discharge capacity (102 mAh/g at 0.1C), and good rate capability. This material broadens the research directions for cathode materials and holds promise as a foundation for the further development of high-performance sodium-ion batteries.
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
ACS Applied Energy Materials
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2024
·
IF 5.4
Lixiong Qian,Rui Huang,Haoran Zhang,Shengxue Yan,Shaohua Luo
Co-free Fe/Mn-based cathodes have become a popular choice for sodium-ion batteries (SIBs) due to their affordability and impressive theoretical capacity. Nevertheless, the issue of their terrible battery life and rate capability continues to be their hindrances. A set of three-factor, three-level orthogonal experiments was adopted, including the calcination temperature, calcination time, and heating rate. And two single-factor experiments were carried out to further optimize the preparation conditions. Finally, the optimal conditions were obtained as follows: the calcination temperature was 900 °C, the calcination time was 12 h, and the heating rate was 5 °C min–1. The layered oxide cathode material Co-free P2-Na2/3Fe1/2Mn1/2O2 was synthesized by the solid phase method. Under the control of the optimal conditions, the P2-Na2/3Fe1/2Mn1/2O2 cathode could yield a remarkable initial discharge specific capacity (179.3 mAh g–1, 0.1 C) and cycle stability (54.6% over 50 cycles). These findings further declared that it was feasible to design Co-free Fe/Mn-based cathode materials with superior performance, which might offer guidance for popularizing cost-effective Fe/Mn-based cathode materials in the future.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Yunchao Liao,Na Wang,Xinyi Dai,Wenwen Zhou,Fuzhong Wu,Jiexi Wang,Haijun Chen,Yi Mai
Ultrahigh-nickel LiNi x Co y Mn 1-x-y O 2 cathode material (Ni content ≥ 0.9) is of great significance for the development of high energy density of lithium-ion batteries. However, its high surface activity leads to more surface residual lithium formation and deterioration of electrochemical performance, especially at high voltage. Here we add NH 4 F and nitrogen-doped carbon nanotubes (CNT) during the dimethyl carbonate (DMC) washing process, and constructed in situ the nano-LiF and CNT composite cathode electrolyte interphase (CEI) layer while removing part of residual lithium, effectively optimizing the surface environment of LiNi 0.9 Co 0.05 Mn 0.05 O 2 . The modified LiNi 0.9 Co 0.05 Mn 0.05 O 2 has a capacity retention rate of 61.3 % after 200 cycles between 2.8 and 4.5 V at 1C, significantly higher than the 46.7 % of the unwashed sample, and a specific discharge capacity of 146.9 mAh g −1 at 5C, compared to 127.5 mAh g −1 for the unwashed sample. Benefit from the alleviation of polarization and the increase of Li + diffusion coefficient, the stable CEI layer provides effective protection for LiNi 0.9 Co 0.05 Mn 0.05 O 2 under 4.5 V, alleviating surface side reactions. In this paper, a simple and effective strategy is developed to optimize the surface of Ni-rich cathode material, which provides a new insight for the treatment of surface residual lithium.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2024
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IF 10.7
Jing Zhang,Jin Chen,Jian Wei,Yanyi Liu,Yuzhao Ma,Xiaofeng Yang,Yanjun Li
The unique structure of medium entropy materials has garnered significant attention in the field of batteries. Medium-entropy spinel ferrite, as a new cathode material for lithium–sulfur batteries, presents boundless possibilities to tailor charge–discharge performance. Herein, abundant oxygen vacancies were implanted into medium-entropy spinel ferrites and utilized as cathode materials for lithium–sulfur batteries to address the challenges associated with the sluggish shuttle and conversion kinetics of lithium polysulfides (LiPSs) during charge–discharge processes in Li–S batteries. The synergistic effects among multiple species highlight the advantages of medium entropy features. The presence of oxygen vacancies mitigates the energy barrier associated with the decomposition reaction, thereby facilitating charge transfer kinetics and promoting LiPSs conversion. Oxygen vacancies can be readily implanted into the medium-entropy spinel ferrite, thereby enabling the distinctive medium-entropy-driven influence of oxygen vacancies on the favorable rate capability and prolonged cycling performance of lithium–sulfur batteries. This study presents a promising approach for utilizing design defects in medium-entropy ferrites within the realm of battery applications.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Progress in Natural Science-Materials International
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2018
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IF 2.572
Datong Zhang,Zhengping Ding,Shuai Zhao,Ying Yang,Yiming Feng,Lei Xiao,Ran Ji,Libao Chen,Weifeng Wei
Li 2 MnSiO 4 -based cathode materials possess reasonable work potentials and high theoretical capacities, while the practical energy/power densities are constrained by their inferior kinetics of Li + diffusion. In this work, the Pmn2 1 -structure Li 2 Fe x Mn 1-x SiO 4 /C materials were synthesized via a solvothermal method and evaluated as Li-ion cathode materials, with notable morphological evolutions and tunable crystallographic habits observed after solvothermal process. The Li 2 Fe 0.33 Mn 0.67 SiO 4 /C material delivers an initial reversible capacity of 250.2 mAh g −1 at 0.1 C (~ 1.51 Li + insertion/extraction, 1 C = 166 mA g −1 ), excellent high-rate capability (52.2 mAh g −1 at 5 C), and good long-term cyclability (64.6% after 196 cycles at 2 C). The enhanced electrochemical properties are attributed to the boosted ion/electron transports induced by preferred morphological and structural characteristics of Li 2 Fe 0.33 Mn 0.67 SiO 4 /C.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
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2023
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IF 3
Hongda Gui,Fei Xu
Rechargeable magnesium batteries (RMBs) attract interests as advantageous energy-storage devices, but the application is being hampered by the deficiency of suitable cathodes. Covalent organic frameworks (COFs) are promising selections because of the flexible organic polymer chains and open matrix. Herein, a new family of COF-based polyimide cathodes is synthesized and investigated as RMB cathodes. The COF cathode exhibits a high Mg-storage capacity of 120 mAh g −1 , as well as high rate capability and good cycleability, suggesting COFs would be a promising family of cathode materials for RMBs.
研究领域:
材料科学
·
能源研究
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）