CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zhuo Chen,Xiufang Cui,Yongzhi Jing,Guo Jin,Xiang Wang,Yongchao Fang,Xinhe Wang,Dianchao Liu,Bin Wang
This study utilizes modulation of ionic disorder and electronegativity differences for targeted component design of high-entropy ceramic compositions. A series of novel multicomponent ceramics with the general formula ( LaGdYSm ) x 2 Yb x 1 Zr 2 O 7 (x 1 +4x 2 = 2, x 1 = 0.6,0.4,0.2,0) were prepared by solid-state reaction. The evolution patterns of their microstructures were analyzed using XRD and TEM, and the anti-sintering ability and thermophysical properties were evaluated. The results confirm that the multicomponent ceramics gradually transform from the coexistence of pyrochlore/fluorite dual-phase structure to pyrochlore structure with the tuning of the size disorder degree. After 50h of exposure to air at 1500 °C, the ceramics retained excellent phase stability. Segregation of La and Yb elements with large differences in radius size occurs, forming a mixture of the La-rich pyrochlore and the Yb-rich fluorite phases. The specimen with the maximum size disorder exhibits the lowest grain growth rate and the greatest thermal insulation properties. Large lattice distortions and sluggish diffusion effects are responsible for the mutual inhibition of grain growth in the two-phase coexistence zone. The thermal insulation properties of the ceramics show well correlated with the degree of the size disorder, further validating the effectiveness of the component design. Meanwhile, the thermal expansion coefficients of prepared ceramic can reach 11.49 × ∼11.58 × 10 −6 K −1 at 1000–1100 °C. The customization principles used in this work fill a gap in the compositional design methodology for multicomponent lanthanum zirconate-based high-entropy ceramics. It is essential for developing rare-earth zirconates with tunable thermophysical properties in the area of thermal barrier coatings.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2022
·Vol. 105
·期 10
·6407-6416
·
IF 4.186
Hao Guo,Yanli Shi,Hailiang Wang,Ruichong Chen,Diyin Ye,Qiwu Shi,Jianqi Qi,Zhijun Liao,Tiecheng Lu
Li 2 TiO 3 has a broad stoichiometric range and wide application prospects such as cathode, tritium breeder, and microwave dielectric materials. Particularly, Li 2 TiO 3 shows a faster tritium release performance and exceptional chemical and radiation stabilities, making it one of the most promising solid breeder materials. Li-rich Li 2 TiO 3 has been developed for years as an advanced breeder material due to its enhanced tritium production and better stability in hydrogen atmosphere. However, the defect chemistry responsible for accommodating excess Li and how the non-stoichiometry improves the material's performance is still unclear. In this work, the crystal structure and non-stoichiometry-induced defects in Li-rich Li 2 TiO 3 were investigated by means of X-ray diffraction, electron spin resonance, and X-ray photoelectron spectroscopy. Results show that oxygen vacancies and cation disorder both play a major role in the incorporation of excess Li. The sintering atmosphere (air/vacuum) has a negligible effect on the formation of the non-stoichiometry-induced defects but will influence the concentration of the oxygen vacancies. The better stability in the reduction atmosphere may be ascribed to the oxygen vacancies inside the Li-rich Li 2 TiO 3 crystals.
研究领域:
材料科学
·
核能工程
·
固体化学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Maolin Yang,Tingting Yang,Mingjie Dong,Zhongyuan Huang,Yuguang Pu,Lei Jin,Rui Wang,Yuxi Luo,Tao Zeng,Yonglin Tang,Jun Chen,Rafal E. Dunin-Borkowski,Ziwei Chen,Yu Qiao,Yinguo Xiao
Mn-rich layered oxides (MRLOs) are promising low-cost cathode materials for sustainable sodium-ion batteries (SIBs). However, the low Mn 4+ /Mn 3+ redox potential limits their energy densities, and the Jahn-Teller distortion that occurs surrounding Mn 3+ at low voltages destabilizes the structure. Additionally, complex ordered structures inherently present in MRLOs hinder Na + migration. In this study, new types of cation ordering structures are discovered in common MRLOs. By regulating oxygen vacancy formation, the transition from short-range to long-range cation ordering is disrupted, effectively mitigating cooperative Jahn-Teller distortion and achieving a 95.3% capacity retention over 1 000 cycles at 8 C. The maximum entropy method (MEM) analysis is performed based on neutron diffraction data, which visualizes significantly optimized Na + diffusion pathways in long-range disordered cathode with enhanced Na + diffusion kinetics. Furthermore, the formation of oxygen vacancy elevates the Mn 4+ /Mn 3+ redox potential, resulting in a competitive energy density of 626 Wh kg −1 within 1.5–4.5 V in a half-cell configuration. This work offers a multiscale approach to precise elucidation of the cathode crystal structure and provides a feasible pathway to optimize sodium-ion cathodes by disrupting long-range cation ordering, ultimately facilitating substantial improvements in electrochemical performance.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yiliang Liu,Xiaolu Liang,Yufei Du,Yao Wang,Zihao Chen,Zhenyu Wang,Haitao Wang,Xin Gu,Jiankun Sun,Jing Zhang,Xiang Liu
The influence of sintering duration ( t s = 7, 10, 13 and 16 h) on the microstructure, A-site cation disorder ( σ 2 ), hopping conduction mechanism and temperature coefficient of resistance characteristics of La 0.81 Sr 0.19 MnO 3 polycrystalline ceramics were investigated in this work. By systematically adjusting the sintering duration, it is observed that the A-site cation disorder has decreased from σ 2 = 4.23 × 10 −3 ( t s = 7 h) to σ 2 = 3.71 × 10 −3 ( t s = 13 h). The changes in the A-site cation disorder increase the ratio of Mn 4+ /Mn 3+ , Mn-O bond lengths and angles of perovskite manganite oxides. The hopping conduction mechanism of the ceramics was examined using the variable range hopping model, and the result verified that the dynamics of charge carriers are significantly impacted by variations in cation disorder. All of the scattering processes in electron-electron, electron-phonon, and electron-magnon in La 0.81 Sr 0.19 MnO 3 ceramics were decreased with cation disorder decreasing. The temperature coefficient of resistivity ( TCR ) achieved its maximum value of 11.19 % K −1 at room temperature (298.56 K) when t s = 13 h. The value of TCR has increased by 38.32 % from 8.05 % K −1 ( t s = 10 h) to 11.19 % K −1 ( t s = 13 h). Therefore, the ceramic has great application potential for infrared bolometers.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Energies
·
2023
·Vol. 16
·期 18
·6740
·
IF 3.2
Qi Liang,Peirong Li,Yue Zhao,Supeng Chen,Jixiang Yin,Yingchun Lyu,Qiang Li,Qinghao Li
Cation-disordered rock salt (DRX) cathodes exhibit high specific capacity due to the simultaneous use of anionic and cationic redox reactions. However, DRX systems face severe challenges that limit their practical applications; a most important challenge is their poor rate performance. In this work, the structure and morphology of Li1.17Ti0.58Ni0.25O2(LTNO) were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), etc. In combination with various electrochemical characterizations, we found that the sluggish kinetics of anionic redox within LTNO can be the key reason for the inferior rate performance. By sample relaxation at moderate temperature and X-ray absorption near edge structure (XANES), the ligand-to-metal charge transfer process is verified to occur between O and Ni and exhibits a prolonged characteristic time of 113.8 min. This time-consuming charge transfer process is verified to be the very fundamental origin of the slow kinetics of oxygen oxidation and reduction. This claim is further supported by the galvanostatic intermittent titration technique (GITT) at different temperatures. These findings provide essential guidance for understanding and further optimizing cathodes with anion redox reactions not only in the context of DRX cathodes but also conventional Li-rich cathodes.Keywords:lithium-ion batteries;cation-disordered cathode;anionic redox reaction;sluggish kinetics
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Small
·
2024
·Vol. 20
·期 23
·2307292
·
IF 13
Yongjian Li,Xinyu Zhu,Yuefeng Su,Lifeng Xu,Lai Chen,Duanyun Cao,Ning Li,Feng Wu
Layered Li-rich oxide cathode materials are capable of offering high energy density due to their cumulative cationic and anionic redox mechanism during (de)lithiation process. However, the structural instability of the layered Li-rich oxide cathode materials, especially in the deeply delitiated state, results in severe capacity and voltage degradation. Considering the minimal isotropic structural evolution of disordered rock salt oxide cathode during cycling, cation-disordered nano-domains have been controllably introduced into layered Li-rich oxides by co-doping of d 0 -TM and alkali ions. Combining electrochemical and synchrotron-based advanced characterizations, the incorporation of the phase-compatible cation-disordered domains can not only hinder the oxygen framework collapse along the c axis of layered Li-rich cathode under high operation voltage but also promote the Mn and anionic activities as well as Li + (de)intercalation kinetics, leading to remarkable improvement in rate capability and mitigation of capacity and voltage decay. With this unique layered/rocksalt intergrown structure, the intergrown cathode yields an ultrahigh capacity of 288.4 mAh g −1 at 0.1 C, and outstanding capacity retention of ≈90.0% with obviously suppressed voltage decay after 100 cycles at 0.5, 1, and 2 C rate. This work provides a new direction toward advanced cathode materials for next-generation Li-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2020
·
IF 16.28
Ke Zhou,Shiyao Zheng,Fucheng Ren,Jue Wu,Haodong Liu,Mingzeng Luo,Xiangsi Liu,Yuxuan Xiang,Chunyang Zhang,Wanli Yang,Lunhua He,Yong Yang
Cation-disordered Li-excess cathodes with oxygen redox reactions are promising candidates for high-energy-density Li ion batteries . Nevertheless, the oxygen redox process that is required for the high capacity often comes with the oxygen loss, which leads to severe capacity degradation and voltage decay. In this work, we have successfully synthesized a series of Li-excess cation-disordered cathodes (Li 1.2 Mn 0.4+x Ti 0.4-x O 2-x F x ) (0 ≤ x ≤ 0.2) with different fluorine (F) contents. The electrochemical performance results show that the Li 1.2 Mn 0.55 Ti 0.25 O 1.85 F 0.15 (LMTOF0.15) exhibits the highest reversible capacity (275 mAh g -1 , under 30 mA g -1 ), cyclability, and voltage retentions. The mapping of resonant inelastic X-ray scattering (mRIXS) and differential electrochemical mass spectroscopy (DEMS) results reveal that the fluorination enhances the reversible lattice oxygen redox reaction while suppressing irreversible gas release and surface reactions. The X-ray Absorption Spectroscopy (XAS) during the initial two cycles shows that F-substitution alleviates the reduction of the Mn valence state during the whole (dis)charge processes in the bulk and at the surface of the material, results in higher average discharge voltage. In addition, the introduction of F improves the structural stability and suppresses local lattice distortion of the material. Therefore, LMTOF0.15 is able to cycle with smaller polarization, less interfacial side reaction and Mn dissolution, and therefore results in enhanced cyclability. This work provides a comprehensive understanding of the fluorination effect on the cationic and anionic redox activities in cation-disordered Li-excess cathodes.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
Advanced Energy Materials
·
2023
·Vol. 13
·期 28
·2300695
·
IF 27.8
Zhi Deng,Diancheng Chen,Mingyang Ou,Yuanpeng Zhang,Jia Xu,Dixing Ni,Zhaoran Ji,Jiantao Han,Yang Sun,Shuai Li,Chuying Ouyang,Zhaoxiang Wang
Recently, a new family of anti-perovskite Li 2 TMSO was discovered as promising cathode materials for Li-ion batteries (LIBs) with superiorities in high specific capacity, low cost, and environmental friendliness. However, the applications of these anti-perovskite materials meet severe challenges in the cyclability and rate performance. Herein, a cation-disordered anti-perovskite type solid solution Li 2 Fe 1− x Mn x SO (LFMSO, x = 0, 0.2, 0.5) with excellent electrochemical performance is reported. On the basis of comprehensive structural characterizations, the role of the cation disordering in LFMSO is clarified. In comparison with Li 2 FeSO (LFSO), the reduced Li-ion diffusion barrier and the increased Li-rich octahedral configurations in LFMSO with higher configurational entropy imply the facilitated long-range Li-ion diffusion and the suppressed phase transition, which favor the high-rate capability and cycling stability. In addition, the large lattice distortion and Coulombic interaction between the anions and cations lead to the breathing of the unit cell during charge/discharge. The variation of the unit cell volume decreases to 2.5% upon Li-ion delithiation. A superstructure is observed in LFMSO for the first time. These findings help to pave the way for the research and development of novel cathode materials for the next generation LIBs.
研究领域:
材料科学
·
电化学
·
固态化学
·
能源存储
·
锂电池
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2024
·
IF 18.9
Yi Liu,Xiang Wu,Hui Feng,Guozhong Lu,Ying Jiang,Xiaobing Lou,Chao Li,Ming Shen,Fushan Geng,Bingwen Hu
Cation-disordered rock-salts (DRX) emerge as an intriguing class of high-capacity cathode materials , garnering significant attention in the development of advanced energy-storage systems. Fluorination strategies have been raised to regulate redox and structure for better DRX electrochemical performance . However, research on the interfacial processes during fluorinated DRX cycling remains limited. Here, we evaluate a highly fluorinated DRX, Li 2 Mn 2/3 Nb 1/3 O 2 F (LMNOF), in different electrolytes to correlate its cycling performance with distinct interfacial evolutions. During cycling in the carbonate-based electrolyte, a thick Mn-containing CEI forms on the LMNOF surface, leading to gradual capacity decay. Intriguingly, the addition of fluoroethylene carbonate (FEC) would bring about surface oxygen loss, Mn-ion dissolution and formation of a fluorinated surface layer by reacting with the LMNOF surface, which critically deteriorate the cycling performance. In comparison, the ether-based electrolyte is compatible with the LMNOF surface, resulting in a more favorable cycling stability. This work sheds light on the interfacial deterioration mechanism of LMNOF cathode in traditional carbonate-based electrolyte, emphasizing the importance of using advanced non-reactive electrolytes to enhance DRX performance.
研究领域:
材料化学
·
电化学
·
能源存储
·
锂离子电池
·
界面科学
·
固态化学
·
先进电池材料
✓ 已验证
DOI
高影响因子
Progress in Natural Science-Materials International
·
2023
·
IF 4.7
Bianzheng You,Zhixing Wang,Ding Wang,Gui Luo,Duo Deng,Guochun Yan,Huajun Guo,Xinhai Li,Wenjie Peng,Mingxia Dong,Jiexi Wang
LiNiO 2 (LNO) is recognized as the most promising cathode material for next-generation lithium-ion batteries owing to its highest energy density and economic benefit in the layered oxide cathode materials systems. However, severe cation disordering, multiple phase transformations and poor lithium-ion diffusion kinetics , which result in rapid degradation of cycling stabilities and rate properties, hinder its further practical applications. Cobalt doping is an effective strategy to address such issues, but the influences of cobalt on LNO materials have not been figured out completely yet. Hence, a systematical investigation of cobalt doping for LiNiO 2 cathode materials prepared by spray pyrolysis is conducted. The addition of cobalt enhances the stabilities of layered structures and suppresses the cation disordering effectively. The multiple-phase transformations during cycling are also alleviated significantly. Furthermore, cobalt doping can decrease charge transfer resistances and improve lithium-ion diffusion kinetics, especially at high de-lithiation states. As a result, the electrochemical performances are improved comprehensively after cobalt doping. The LNO with optimal doping amount exhibits an improved capacity retention of 78.0% after 100 cycles as compared with 64.9% for pristine LNO, and an outstanding rate performance of 167.2 mA h g −1 with the current density of 5 C (1 C = 200 mA g −1 ).
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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Chengyu Mo,Yutao Yang,Zhenyu Wang,Yanpeng Lv,Rongzheng Tian,Zixiang Zhao,Hongzhou Zhang,Chunliang Li,Lianqi Zhang,Yongan Yang,Dawei Song
Sulfide solid electrolytes have attracted wide attention due to their high ionic conductivity . Li 6 PS 5 Cl is one of the most promising electrolytes for all-solid-state lithium batteries with high-energy-density. It is reported that the disordered arrangement of Cl - in the aragonite structure has a significant effect on the conductivity of Li 6 PS 5 Cl. In this work, the disorder of anion sites is modestly regulated by adjusting the ratio of S and Cl in Li 6−x PS 5−x Cl 1+x electrolyte. In addition, to verify the commonality of this strategy, Li 5.6 PS 4.6 Cl 1.4 is prepared using self-made Li 2 S, and similar results are obtained. On this basis, the density of Li 5.6 PS 4.6 Cl 1.4 electrolyte sheet is improved by hot-pressing, which can successfully inhibit the growth of lithium dendrites . As expected, the ionic conductivity of the sulfide electrolyte and the electrochemical performance of the ASSLBs are greatly improved. A highest ionic conductivity of 8.2 × 10 −3 S cm −1 of Li 5.6 PS 4.6 Cl 1.4 is obtained at room temperature. A high capacity retention of 99.99 % is maintained for NCM811 @Li 2 O//Li 5.6 PS 4.6 Cl 1.4 //Li-In system after 400 cycles at 1 C with ultra-high cathode loading of 35.6 mg cm −2 . Besides, the cost of sulfide electrolytes can be reduced as the decreased usage of Li 2 S. This work proposes a novel synthesis method of low-cost and high-performance Li 6−x PS 5−x Cl 1+x electrolytes.
研究领域:
材料科学
·
电化学
·
能源存储
·
固态离子学
·
电池技术
✓ 已验证
DOI
高影响因子
Advanced Energy Materials
·
2022
·Vol. 12
·期 30
·2201130
·
IF 29.698
Wei Wu,Mingxian Liu,Yi Pei,Wenjin Li,Wang Lin,Qiyao Huang,Man Wang,Haitao Yang,Libo Deng,Lei Yao,Zijian Zheng
High-power lithium-ion batteries (LIBs) are critical for power-intensive applications; however, their development is largely hindered by the lack of anode materials that have stability and high capacity at high charging/discharging rates. Herein, a cationic disordering strategy is reported to build an ideal high-power anode with boosted intercalation kinetics and a stable framework. A novel titanium niobate (TiNb 2 O 7 ) anode with unique predistorted Nb(Ti)O 6 octahedrons (pd-TNO) is developed by introducing cation disorder, which allows ultrafast Li + storage within seconds and exceptional stability over long cycling at high rates. The pd-TNO delivers an outstanding specific capacity of 153 mAh g −1 at 100 C, 20 times higher than that of conventional TNO anodes without cationic disordering, and retains 42.8% of the capacity after 15,000 cycles. Using the pd-TNO anode, a high-power LIB with an unprecedented power density of 91,197 W kg −1 at 200 C, which is approximately eight times higher than that of the advanced commercial high-power anode Li 4 Ti 5 O 12 (11,813 W kg −1 at 50 C), is demonstrated. Importantly, the pd-TNO is prepared under ambient conditions via a high-throughput process, and it exhibits considerable potential for scalability for practical applications.
研究领域:
材料科学
·
储能
·
电化学
·
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）