JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
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IF 9.7
Wenfang Cui,Mei Ma,Yongmei Sun,Qingwen Fan,KeYu Zhang,Chengcheng Shi
TiP 2 O 7 is a lithium-ion batteries anode material with outstanding stability and high safety due to its strong polyanion three-dimensional frame structure. However, poor electrical conductivity severely represses the rate capability of TiP 2 O 7 anode. Herein, a porous TiP 2 O 7 /nitrogen-doped carbon (CN) composite with tailored (6 3 0) and (6 0 0) preferential crystallographic orientation is achieved by the ball-milling and thermal treatment strategy. The TiP 2 O 7 /CN (6 3 0) anode retains specific capacities of 194.3 and 128.9 mA h/g at high current densities of 5 and 10 A/g, respectively, superior than that of the TiP 2 O 7 /CN (6 0 0). Remarkably, kinetic analysis reveals that the charge storage process in the TiP 2 O 7 /CN (6 3 0) anode is predominantly diffusion-controlled, with the diffusion-controlled capacity contributing up to 52 % even at a high scan rate of 2 mV/s. Density functional theory calculation confirms the lower lithium ions migration energy barrier of (6 3 0) crystallographic orientation of TiP 2 O 7 . In addition, due to the homogeneity of porous structure and composition, the TiP 2 O 7 /CN (6 3 0) anode maintains a capacity of 389mA h/g after 1000 cycles at 1 A/g. Thereby, the synthesis strategy for preferred orientation TiP 2 O 7 -based anode is instructive for the structural design of high-rate metal-based composite oxides for lithium-ion batteries.
研究领域:
材料科学
·
电化学
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产品关联
DOI
PubMed
高影响因子
Nano Research
·
2020
·Vol. 14
·期 1
·139-147
·
IF 8.183
Pan Jun,Wang Nana,Li Lili,Zhang Feng,Cheng Zhenjie,Li Yanlu,Yang Jian,Qian Yitai
Ti-based anode materials in sodium ion batteries have attracted extensive interests due to its abundant resources, low toxicity, easy synthesis and long cycle life. However, low Coulombic efficiency and limited specific capacity affect their applications. Here, cubic-phase TiP 2 O 7 is examined as anode materials, using in-situ/ex-situ characterization techniques. It is concluded that the redox reactions of Ti 4+ /Ti 3+ and Ti 3+ /Ti 0 consecutively occur during the discharge/charge processes, both of which are highly reversible. These reactions make the specific capacity of TiP 2 O 7 even higher than the case of TiO 2 that only contains a simple anion, O 2− . Interestingly, Ti species participate only one of the redox reactions, due to the remarkable difference in local structures related to the sodiation process. The stable discharge/charge products in TiP 2 O 7 reduce the side reactions and improve the Coulombic efficiency as compared to TiO 2 . These features make it a promising Ti-based anode for sodium ion batteries. Therefore, TiP 2 O 7 @C microflowers exhibit excellent electrochemical performances, ~ 109 mAh·g −1 after 10,000 cycles at 2 A·g −1 , or 95.2 mAh·g −1 at 10 A·g −1 . The results demonstrate new opportunities for advanced Ti-based anodes in sodium ion batteries.
研究领域:
材料科学
·
能源科学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2026
·
IF 4.4
Cui Wenfang,Zhu Mingzhu,Sun Yongmei,Zhang Keyu,Ma Mei
The three-dimensional framework for lithium storage endows TiP 2 O 7 with excellent stability and considerable capacity. However, its practical application is hindered by poor electrical conductivity and an unclear understanding of its structural evolution. Herein, we present a nitrogen-doped carbon-coated TiP 2 O 7 composite prepared by a straightforward and scalable surface modification strategy, which exhibits superior rate capability compared to previous reports. Specifically, it achieves specific capacities of 435, 341, and 263 mA h g −1 at current densities of 2, 5, and 10 A g −1 , respectively. Kinetic analysis confirms that the nitrogen-doped carbon coating on TiP 2 O 7 surface significantly accelerates the interfacial charge transfer, leading to a dominant pseudocapacitive behavior. Importantly, ex-situ transmission electron microscopy characterization reveals that the TiP 2 O 7 in the composite evolves into homogeneous nanocrystals after 100 cycles at a low current density of 0.2 A g −1 . By contrast, despite the TiP 2 O 7 transforming into nanocrystals with inconsistent sizes and reduced crystallinity after 1000 cycles at a high current density of 1 A g −1 , the effective coating of N-doped carbon preserves the capacity of the anode at up to 462.6 mA h g −1 . These findings suggest that this universal strategy can significantly enhance the performance of TiP 2 O 7 -based anode materials for lithium-ion batteries. Graphical abstract
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Wenfang Cui,Yongmei Sun,KeYu Zhang,Chengcheng Shi,Peng Fu,Mei Ma
The development of high-performance TiP 2 O 7 anode materials has been fundamentally limited by their intrinsically poor electronic conductivity and slow Li + diffusion kinetics. Herein, we report an innovative ionic liquid-mediated strategy that simultaneously engineers oxygen vacancies and nitrogen-doped carbon in hierarchical TiP 2 O 7 architectures. Through pyrolysis gas reduction, oxygen vacancies are introduced into the TiP 2 O 7 lattice, promoting the formation of C P bonds and defect energy levels while broadening the lithium ions transport channels. The concurrent formation of a nitrogen-doped carbon matrix, rich in pyridinic-N configurations, establishes a highly conductive network and optimizes electrode-electrolyte interfacial dynamics. The co-engineered material delivers exceptional rate capability (301.5 and 241.7 mA h g −1 at 5 and 10 A g −1 , respectively), doubling the capacity of the ionic liquid-free counterpart. First-principles calculations elucidate the underlying mechanisms: oxygen vacancies substantially reduce the Li + diffusion barrier by 29% (from 0.42 eV to 0.30 eV), while synergistic coupling with nitrogen-doped carbon creates a 0.73 eV in-gap state that effectively boosts charge transfer kinetics. This multiscale engineering strategy, which synergistically integrates atomic-scale defect control with mesoscopic interface optimization, establishes a generalizable design principle for next-generation high-rate electrode materials.
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DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2024
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IF 8.1
Mingzhu Zhu,Binhao Yu,Wenfang Cui,Yongmei Sun,Mei Ma
Carbon coating is a beneficial method for improving surface capacitive behavior, electron transfer kinetics and cyclic stability of three-dimensional lattice lithium-embedded anode materials. Herein, we adopt one-step pyrolysis to achieve carbon-covered TiP 2 O 7 supported by a three-dimensional carbon skeleton utilizing phytic acid and glucose as carbon sources. The two-dimensional amorphous carbon layer on TiP 2 O 7 surface improves the initial Coulombic efficiency and rate capacity by inhibiting the irreversible embedding of lithium ions and reducing the interfacial charge transfer impedance. The three-dimensional carbon skeleton not only forms a conductive pathway between the carbon-covered TiP 2 O 7 , but also its large specific surface area, randomly oriented and defective carbon layer provide extra lithium storage sites and capacitive contribution. In addition, the specific capacity of the TiP 2 O 7 /C composite is still as high as 314.5 mA h g −1 after 1000 cycles at 1 A g −1 . A TiP 2 O 7 /C//LiFePO 4 full cell delivers a high energy density of 273.96 Wh kg −1 at 0.153 kW kg −1 , and retains 114.43 Wh kg −1 even at the power density of 4.086 kW kg −1 . The multi-dimensional carbon modification strategy has improved the electrochemical performance of TiP 2 O 7 -based anode materials, providing a model for synthesizing other high-performance anode materials.
研究领域:
材料科学
·
能源化学
·
电化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）