Nanomaterials
·
2024
·Vol. 14
·期 24
·1989
·
IF 4.4
Kexin Zheng,Jiawei Wang,Haifeng Wang,Zhengqing Pei,Qian Wang,Xinjie Zhou,Dehua Ma,Ju Lu
The P2-Na0.7MnO2.05cathode material has long been constrained by phase transitions induced by the Jahn–Teller (J–T) effect during charge–discharge cycles, leading to suboptimal electrochemical performance. In this study, we employed a liquid phase co-precipitation method to incorporate Ti during the precursor Mn3O4synthesis, followed by calcination to obtain Na0.7TixMn(1−x)O2.05materials. We investigated the effects of Ti doping on the structure, morphology, Mn3+concentration, and Na+diffusion coefficients of Na0.7TixMn(1−x)O2.05. Our findings revealed that the 7% Ti-doped NTMO-007 sample exhibited reduced grain agglomeration and smaller particle sizes compared to the undoped sample, thereby enhancing the electrode–electrolyte contact area and electrochemical activity. Additionally, Ti doping increased the crystal cell volume of Na0.7MnO2.05and broadened the Na+transport channels, significantly enhancing the Na+diffusion coefficient. At a 0.5 C rate, the NTMO-007 sample demonstrated a specific capacity of 143.3 mAh g−1with an 81.8% capacity retention after 100 cycles, markedly outperforming the undoped NMO sample, which had a capacity retention of only 61.5%.
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
IONICS
·
2019
·Vol. 25
·期 10
·4805-4815
·
IF 2.289
Sun Tianjiao,Yao Xiaolin,Luo Yanxiang,Fang Minhua,Shui Miao,Shu Jie,Ren Yuanlong
Aqueous magnesium ion batteries have been identified as potential electrochemical energy storage system due to their similar electrochemical properties to lithium, safety, high abundance, and low cost. Here, micron-sized Na 0.7 MnO 2.05 is prepared by a facile sol-gel method used for cathode material in aqueous magnesium ion batteries. XRD, XPS, SEM, TEM, and EDS were used to test the composition, structure, and morphology of Na 0.7 MnO 2.05 . Na 0.7 MnO 2.05 material is electro-chemical active although the intercalation/deintercalation is much difficult for Mg 2+ . The reversible specific capacities of the Na 0.7 MnO 2.05 cathode material are estimated to be ca. 40, 35, 22, and 13 mAh·g −1 at the current density of 1 C, 2 C, 5 C, and 10 C, respectively. When the current density comes back to 1 C, the charge capacities recover to 40 mAh·g −1 . Furthermore, EIS and GITT measured show that the diffusion coefficient of Mg 2+ ion in lattice of Na 0.7 MnO 2.05 varies from 2.17 × 10 −11 cm 2 ·s −1 to 7.81 × 10 −11 cm 2 ·s −1 in charge process and changes from 6.34 × 10 −12 cm 2 ·s −1 to 7.14 × 10 −11 cm 2 ·s −1 in discharge process.
研究领域:
材料科学
·
电化学
·
能量存储
·
电池技术
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2020
·Vol. 126
·期 8
·658
·
IF 1.81
Gu Fanpei,Yao Xiaolin,Sun Tianjiao,Fang Minhua,Shui Miao,Shu Jie,Ren Yuanlong
Aqueous rechargeable sodium-ion batteries (ARSB) have great potential as large-scale storage devices owing to their low cost, high energy density, safety, and environmental friendliness. Here, micron-sized Na 0.7 MnO 2.05 , fabricated by a facile sol–gel method, is reported as a novel cathode material for ARSB and has been characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), selected area electron diffraction/energy dispersive spectroscopy (ED/EDS) and X-ray photoelectron spectroscopy (XPS). As revealed, the material is perfectly synthesized. The Na 0.7 MnO 2.05 electrode delivers an initial charge specific capacity of 42.6 mA h g −1 at a current density of 50 mA g −1 . Compared with the capacity of 100th cycle (the highest discharge specific capacity of 52 mA h g −1 ), a capacity retention of 90.1% after 600 cycles is still observed. Good rate performance and excellent long-term cycling capability are also demonstrated. Unique morphology, medium-sized and mono-disperse particles facilitate the diffusion of Na + in the electrode, which is also beneficial for Na 0.7 MnO 2.05 electrode to exhibit excellent electrochemical performance.
研究领域:
材料科学
·
电化学
·
储能
·
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）