Coatings
·
2023
·Vol. 13
·期 3
·626
·
IF 3.4
Xinglong Chen,Wenyue Guo,Rui Li,Peng Du,Xiaowen Zhan,Shan Gao
The development of cobalt-free P2-Na2/3Ni1/3Mn2/3O2cathodes is hampered by poor electrochemical performance, resulting from structural instability during high-voltage cycling. Herein, Li+and F−ions are introduced simultaneously via a simple sol–gel method. The F not only enters the lattice but forms chemically stable NaF on the surface. The modified electrode delivered significantly better electrochemical performance than the pristine one, including much-enhanced capacity retention (64% vs. 36%, 100 cycles) at 0.5 C and a four-time higher capacity output at 10 C. The ex situ XRD and in situ Raman analysis revealed cyclability enhancement mechanisms in terms of inhibiting the P2–O2 phase transition and Na+/vacancy ordering. The conductivity measurements (based on AC impedance and DC polarization) and GITT analysis proved, on both bulk material and electrode levels, that Na+conduction and, thus, rate performance is notably promoted by doping. The individual contribution of Li and F to the overall performance improvement was also discussed. Furthermore, a solid-state sodium-metal battery was successfully demonstrated with the modified cathode. The above results verify that Li+/F−incorporation can enable enhancements in both cyclability and rate capability of the P2-Na2/3Ni1/3Mn2/3O2cathodes and are expected to provide a new perspective for the rational design of high-performance layered oxide cathode materials for progressive sodium-ion batteries.
研究领域:
材料科学
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电化学
·
能源存储
·
固态电池
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离子传导
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功能材料
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电池材料
✓ 已验证
DOI
高影响因子
Chemical Science
·
2024
·Vol. 16
·期 1
·425-429
·
IF 7.6
Ang Li,Ziqi Wang,Yunhua Xu
A novel buckled-layer K1.39Mn3O6 cathode was synthesized, featuring P2-oxygen stacking and P3-K sites. The presence of two independent manganese sites significantly influences the charge distribution and diffusion pathways of potassium ions during the charge and discharge processes, resulting in exceptional electrochemical performance. A reversible capacity of 105 mA h g−1 at 100 mA g−1 and remarkable rate capability of 70 mA h g−1 at 1 A g−1 were achieved, surpassing those of most previously reported layered transition metal oxide cathodes. The findings facilitate the development of innovative cathode materials.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 26
·12109-12116
·
IF 3.3
Ming-Hui Cao,Ren-Yan Li,Fen-Fen Huang,Xin-Yin Cai,Miao Cui,Shi-Ya Lin,Jing-Yang Tian,Yuan-Ping Jiang,Zulipiya Shadike,Zheng-wen Fu
P2-Na0.6Li0.11Fe0.27−xMn0.62YxO2 (x = 0, 0.5%, 1%, and 2%) cathode materials were successfully prepared using a traditional solid-state method with ball milling-assisted modification. The effect of Y-doping on the crystal structure, grain size, morphology and sodium storage performance of Na0.6Li0.11Fe0.27Mn0.62O2 was investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), galvanostatic charge–discharge cycling tests, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results demonstrated that the ball-milling pre-treatment method could effectively reduce the grain size and mitigate the aggregation of Na0.6Li0.11Fe0.27Mn0.62O2. Additionally, reasonable Y-doping (x = 1%) significantly enhances the rate capability and cycling stability of Na0.6Li0.11Fe0.27Mn0.62O2via improving the Na+ diffusion kinetics and the reversibility of the oxygen redox reaction. These results indicate that Na0.6Li0.11Fe0.26Mn0.62Y0.01O2 is a promising candidate material for high-rate and long-life cathodes for Na-ion battery application.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机固体化学
·
电池技术
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2025
·
IF 9.8
Yongxiang Yuan,Jianglong Kang,Shengping Jin,Dengdeng Ai,Wenying Zhao,Jiatai Wang,Yulong Kang,Xiaoyi Hou
P2-type layered Mn-based excess metal oxide cathode is considered to be one of the most promising cathode materials for sodium-ion batteries (SIBs) due to the open sodium ion diffusion channels and low diffusion energy barrier. However, the deep charge/discharge process of the P2-type layered oxide cathodes at high potential leads to the displacement and irreversible alterations of the crystal structure, thereby resulting in poor rate capability and deteriorated capacity retention. The charge/discharge curves are smoothed after Fe doping. The specific discharge capacity, rate capability and cycling stability of the samples are significantly improved by Fe-doping. When x = 0.03, the obtained Na 0.6 Mn 1-x Fe x O 2 cathode delivers excellent electrochemical performance. The initial discharge specific capacity of the cathode is 193.14 mAh g −1 at 0.1C, and can remain 91.05 mAh g −1 after 100 cycles. The capacity retention rate is as high as 86.02 % when the current density turn back to 0.1C after cycles at different current densities. The present work may propose a strategy to improve P2-type layered Mn-based cathode materials for sodium-ion batteries by a doping method, which will be of great significance for the commercialization of sodium-ion batteries.
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2024
·
IF 2.6
Xinhua Sun,Yan Zhang,Jianmin Zhang,Zongmin Zheng
With the surging demand for green energy and renewable energy, as well as the shortage and uneven distribution of global lithium resources, sodium-ion batteries are gaining increasing attention as competitive alternatives. Due to their advantages of high energy density, high safety performance and environmental friendliness, P2 layered oxides have wide application prospects as the positive electrode of sodium ion batteries. However, their practical applications face numerous obstacles due to their complex phase transitions at high voltages, leading to poor cycling stability and rate capability. In this study, a P2-type Na0.67Ni0.2Mn0.8O2 layered oxide cathode material was successfully prepared via a two-step method using ultra-nano-sized precursors. Meanwhile, the sintering temperature was optimized for its influence on phase as well as the electrochemical properties of cathode material for sodium-ion batteries. The materials were characterized in terms of their morphology, structure, and electrochemical properties using SEM, XRD, EDX, and galvanostatic charge–discharge tests. Compared to the traditional one-step solid-state method, the PS-900 material obtained by a two-step approach exhibited a reversible capacity of over 150 mA h g−1 at 0.1 C and the capacity retention reached nearly 70% after 200 cycles at 1 C. These results indicate the widespread potential application of the novel P2-type layered oxide cathode material in sodium-ion batteries.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Yang Jiang,Wenhui Li,Kun Luo
P2-type layered oxide materials have attracted considerable interest because of their high safety and low cost. However, P2-type materials suffer from complicated Na+/vacancy ordering and undesirable phase transitions, resulting in staircase-like electrochemical curves accompanied by fast capacity fading and poor rate performance. A P2-type layered cathode material with high-entropy cation configurations, Na0.85Li0.08Mg0.04Ni0.22Al(B)0.04Mn0.62O2 (HEO), is designed and successfully synthesized in this work. The presence of various metal ions in the transition metal layers imposes an influence on the Na+/vacancy arrangement in the alkali layers, as evidenced by the change of the interlayer distance associated with the electrostatic repulsion. HEO exhibits a smooth electrochemical process without obvious voltage plateaus within 2.0–4.3 V and delivers a reversible capacity of 115 mA h g–1. Structural characterizations indicate that HEO undergoes a complete solid–solution reaction without undesirable phase transitions over the whole voltage range, which facilitates ultrasmall volume variation (0.6%) and fast Na+ ion diffusion (10–9 cm2 s–1) in the electrochemical process. The HEO material therefore shows excellent electrochemical performances with high rate performance (91 mA h g–1 at a current density of 480 mA g–1) and high capacity retention in a wide temperature range from −45 to 55 °C (after 100 cycles, the batteries show 80% capacity retention at 55 °C, 87% at room temperature, and 92% at −45 °C). The results described in this work demonstrate a method to inhibit the complicated staircase-like electrochemical profiles induced by either Na+/vacancy ordering or undesirable P–O phase transitions in P2-type oxide cathode materials and a useful strategy for enhancing the electrochemical performance of P2-type cathode materials for all-climate sodium-ion batteries.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Zheng-Yao Li,Rui Gao,Limei Sun,Zhongbo Hu,Xiangfeng Liu
In this work, Zr 4+ doped P2-Na 0.75 Mn 0.55 Ni 0.25 Co 0.05 Fe 0.10 Zr 0.05 O 2 has been synthesized and investigated as high-rate sodium-ion battery cathode material for the first time. XRD results indicate that Zr-ion with a big size cannot completely dissolve into the crystal structure, but the residual ZrO 2 shows little impact on the electrochemical performance in comparison with the post-added ZrO 2 . With the substitution of Zr 4+ for Fe 3+ , the lattice parameter a decreases but c increases, resulting in the reduced lattice volume. In comparison with the Zr-free sample, Na 0.75 Mn 0.55 Ni 0.25 Co 0.05 Fe 0.10 Zr 0.05 O 2 (Zr05) can deliver a discharge capacity of about 95, 74, 61 and 53 mAh g −1 at 2C, 5C, 8C and 10C. At the current density of 2C, the capacity retention after 100 cycles has increased from 57% of Zr0 to 74% of Zr05. The results demonstrate that Zr-ion substitution can effectively improve the rate performance and cycling stability of P2-structure cathode materials. The role of Zr 4+ can be summarized as follows: (1) Zr-O ( △H f 298K (Zr-O) = 760 kJ mol −1 ) has a stronger bond energy than that of Fe O ( △H f 298K (Fe-O) = 409 kJ mol −1 ), which enhances the structure stability and cycling performance; (2) the aliovalent substitution of Zr 4+ for Fe 3+ enhances the electronic conductivity, which is favorable for the rate capability; (3) the substitution of Zr 4+ for Fe 3+ can be beneficial to Na + conduction because it increases disorder in the transition metal (TM) layers and can prevent Na+/vacancy ordering, which further enhances the rate capability.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2024
·Vol. 30
·期 25
·e202400088
·
IF 3.9
Xin Li,Xin Lai,Qingquan Kong,Xuguang An,Jing Zhan,Xiaolei Li,Xiaonan Liu,Weitang Yao
P2-type layered manganese-based oxides have attracted considerable interest as economical, cathode materials with high energy density for sodium-ion batteries (SIBs). Despite their potential, these materials still face challenges related to sluggish kinetics and structural instability. In this study, a composite cathode material, Na 0.67 Ni 0.23 Mn 0.67 V 0.1 O 2 @Na 3 V 2 O 2 (PO 4 ) 2 F was developed by surface-coating P2-type Na 0.67 Ni 0.23 Mn 0.67 V 0.1 O 2 with a thin layer of Na 3 V 2 O 2 (PO 4 ) 2 F to enhance both the electrochemical sodium storage and material air stability. The optimized Na 0.67 Ni 0.23 Mn 0.67 V 0.1 O 2 @5wt %Na 3 V 2 O 2 (PO 4 ) 2 F exhibited a high discharge capacity of 176 mA h g −1 within the 1.5-4.1 V range at a low current density of 17 mA g −1 . At an increased current density of 850 mA g −1 within the same voltage window, it still delivered a substantial initial discharge capacity of 112 mAh g −1 . These findings validate the significant enhancement of ion diffusion capabilities and rate performance in the P2-type Na 0.67 Ni 0.33 Mn 0.67 O 2 material conferred by the composite cathode. Graphical We propose a composite cathode material, Na 0.67 Ni 0.23 Mn 0.67 V 0.1 O 2 @Na 3 V 2 O 2 (PO 4 ) 2 F, featuring synergistic modification through doping and coating. The optimized Na 0.67 Ni 0.23 Mn 0.67 V 0.1 O 2 @5wt %Na 3 V 2 O 2 (PO 4 ) 2 F exhibited a high discharge capacity of 176 mAh g −1 within the 1.5–4.1 V range at a low current density of 17 mA g −1 . At an increased current density of 850 mA g −1 within the same voltage window, it still delivered a substantial initial discharge capacity of 112 mAh g −1 .
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固体化学
✓ 已验证
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2023
·
IF 6.1
Danlei Qiao,Yixuan Zhang,Chang Su,Guoqiang Liu,Qingxiang Wang,Lei Wen
Al-doped Fe-Mn and Ni-Mn based materials with P2-type layered structure has been synthesized and tested as a positive electrode material for rechargeable sodium batteries. The modification mechanisms of Al doping in Fe-Mn and Ni-Mn based materials have been discussed. The synthesized Al-doped Ni-Mn based material Na 0.67 Mn 0.8 Ni 0.16 Al 0.04 O 2 delivers a reversible capacity of 135.1 mAh g −1 , which corresponds to 92.1% of the initial capacity with excellent cyclability for 200 cycles. What’s more, it can still remain a capacity of 96.2 mAh g −1 at a current density of 2000 mA g −1 . When the voltage range increase to 1.5 – 4.3 V, its initial discharge capacity can reach 190.3 mAh g −1 .
研究领域:
材料科学
·
电化学
·
能量存储
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2023
·
IF 13.1
Yiran Sun,Pengfei Zhou,Siyu Liu,Zhongjun Zhao,Yihao Pan,Xiangyan Shen,Xiaozhong Wu,Jinping Zhao,Junying Weng,Jin Zhou
P2-Na 0.67 Ni 0.33 Mn 0.67 O 2 (NNMO) is promising cathode material for sodium-ion batteries (SIBs) due to its high specific capacity and fast Na + diffusion rate. Nonetheless, the irreversible P2-O2 phase transformation, Na + /vacancy ordering, and transition metal (TM) dissolution seriously damage its cycling stability and restrict its commercialization process. Herein, Na occupation manipulation and interface stabilization are proposed to strengthen the phase structure of NNMO by synergistic Zn/Ti co-doping and introducing lithium difluorophosp (LiPO 2 F 2 ) film-forming electrolyte additive . The Zn/Ti co-doping regulates the occupancy ratio of Na e /Na f at Na sites and disorganizes the Na + /vacancy ordering, resulting in a faster Na + diffusion kinetics and reversible P2-Z phase transition for P2-Na 0.67 Ni 0.28 Zn 0.05 Mn 0.62 Ti 0.05 O 2 (NNZMTO). Meanwhile, the LiPO 2 F 2 additive can form homogeneous and ultrathin cathode-electrolyte interphase (CEI) on NNZMTO surface, which can stabilize the NNZMTO-electrolyte interface to prevent TM dissolution, surface structure transformation, and micro-crack generation. Combination studies of in situ and ex situ characterizations and theoretical calculations were used to elucidate the storage mechanism of NNZMTO with LiPO 2 F 2 additive. As a result, the NNZMTO displays outstanding capacity retention of 94.44% after 500 cycles at 1C with 0.3 wt% LiPO 2 F 2 , excellent rate performance of 92.5 mA h g −1 at 8C with 0.1 wt% LiPO 2 F 2 , and remarkable full cell capability. This work highlights the important role of manipulating Na occupation and constructing protective film in the design of layered materials, which provides a promising direction for developing high-performance cathodes for SIBs.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
·
电池技术
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Yu Duan,Zihan Ma,Jiaxuan He,Yingying Huang,Shuo Bao,Jinlin Lu
P2-type layered cathode materials have low energy density due to low initial Na content. In this research, high sodium content P2-type cathode material Na0.8Li0.08Ni0.23Mn0.67Cu0.1O1.92F0.08 (NMC-LF), was synthesized by a simple high-temperature solid-phase method. The strong electronegativity of F allows the local TM-O bond to be transformed into a TM-F bond, and the TMO6 octahedron becomes more stable. The doping of Li+ not only maintains structural stability but also transforms the two-phase reaction in the high-voltage range into a solid-solution reaction. This leads to an effective suppression of the irreversible P2–O2 phase transition in the high-voltage region. At 20 mA·g–1, the initial discharge capacity of NMC-LF reaches 131.05 mAh·g–1. At a high current density of 200 mA·g–1, the discharge capacity reaches 101.9 mAh·g–1 and remains at 99.31% after 150 cycles. The diffusion coefficient of NMC-LF is as high as 8.67 × 10–13 cm2·s–1. Furthermore, the structural evolution during material formation is elaborated by high-temperature XRD, and it is determined that there are no impurities at 900 °C. Under the joint synergy of Li/F/Cu and the design of high sodium content, the long-cyclic and high-rate performance has been significantly improved. In-situ XRD tests show that Li/F/Cu codoping inhibits the P2–O2 phase transition and enhances structural reversibility. This provides a new idea for the research of layered cathode materials.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2021
·
IF 9.676
Pengfei Zhou,Jing Zhang,Zhennan Che,Zuhao Quan,Ju Duan,Xiaozhong Wu,Junying Weng,Jinping Zhao,Jin Zhou
P2-Na 0.67 Ni 0.33 Mn 0.67 O 2 is considered as a promising cathode material for sodium-ion battery (SIBs) because of its high capacity and discharge potential. However, its practical use is limited by Na + /vacancy ordering and P2-O2 phase transition. Herein, a Ti 4+ /F − co-doping strategy is developed to address these issues. The optimal P2-Na 0.67 Ni 0.33 Mn 0.37 Ti 0.3 O 1.9 F 0.1 exhibits much enhanced sodium storage performance in the high voltage range of 2.0–4.4 V, including a cycling stability of 77.2% over 300 cycles at a rate of 2 C and a high-rate capability of 87.7 mAh g −1 at 6 C. Moreover, the P2-Na 0.67 Ni 0.33 Mn 0.37 Ti 0.3 O 1.9 F 0.1 delivers reversible capacities of 82.7 and 128.1 mAh g −1 at −10 and 50 °C at a rate of 2 C, respectively. The capacity retentions over 200 cycles at −10 °C is 94.2%, implying more opportunity for practical application. In-situ X-ray diffraction analysis reveals that both P2-O2 phase transitions and Na + /vacancy ordering is suppressed by Ti 4+ /F − co-doping, which resulting in fast Na + diffusion and stable phase structure. The hard carbon//P2-Na 0.67 Ni 0.33 Mn 0.37 Ti 0.3 O 1.9 F 0.1 full cell exhibits a high energy density of 310.2 Wh kg −1 and remarkable cyclability with 82.1% retention after 300 cycles at 1 C in the voltage range of 1.5–4.2 V. These results demonstrate that the co-doping Ti 4+ /F − is a promising strategy to improve the electrochemical properties of P2-Na 0.67 Ni 0.33 Mn 0.67 O 2 , providing a facile tactic to develop high performance cathode materials for SIBs.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
·
电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）