INORGANIC CHEMISTRY
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2025
·
IF 4.7
Weishun Jian,Xinyu Hu,Jinqiang Gao,Jingyao Zeng,Yu Mei,Haoji Wang,Ningyun Hong,Jiangnan Huang,Kai Wang,Wentao Deng,Guoqiang Zou,Hongshuai Hou,Hongyi Chen,Xiaobo Ji
Na4Fe3(PO4)2(P2O7) (NFPP) is a promising cathode material for sodium-ion batteries with cost-effectiveness and structural stability. However, its electrochemical behaviors are seriously hindered by its [P2O7] distortion at high voltage. To address this challenge, we introduce a distortion criterion and optimize the local crystal field environment by incorporating Cr3+ into Fe3 sites adjacent to [P2O7]. This substitution elongates Fe1–O bonds, enhances Fe1 activity, and suppresses [P2O7] distortion, facilitating fast Na+ diffusion and structural reversibility, as validated by X-ray absorption fine structure (XAFS) and density functional theory (DFT) calculations. Based on c-axis changes during high-voltage operation, a quantitative method for assessing [P2O7] distortion is proposed and confirmed by operando X-ray diffraction (XRD). The optimized NFPP-0.15Cr exhibits exceptional rate performance (91.74 mAh g–1 at 50C), long-term cycling stability (88.81% capacity retention after 10,000 cycles at 50C), and wide temperature tolerance (−40 to 60 °C). This study provides a strategic approach for designing high-performance iron-based mixed phosphate cathodes, advancing their practical application in sodium-ion batteries.
研究领域:
材料科学
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能源存储
✓ 已验证
DOI
PubMed
高影响因子
Micro & Nano Letters
·
2018
·Vol. 13
·期 3
·393-396
·
IF 0.841
Ting Fan,Jiantao Lü,Yongfa Huang,Guoji Li
Monodisperse oleic acid (OA) modified Eu 3+ and Li + codoped CaF 2 nanoparticles are presented in this work. The as-obtained nanoparticles, with a hexagonal shape, can be well-dispersed in organic apolar solvents. The incorporation of Li + ions in CaF 2 :Eu 3+ does not lead to new crystalline phases. The main diffraction peaks are found to shift to small angles when codoped with 7 mol% Li + , while a reverse shift can be noted with the codoping amount increasing to 9 mol% Li + , indicating that the codoped Li + enables the crystal field environment of Eu 3+ to be changed. The excitation and luminescence intensities of all peaks indexed to Eu 3+ have enhanced apparently when codoped with 7 mol% Li + ions. The lifetime of the 5 D 0 state of Eu 3+ ions is also increased by introducing 7 mol% of Li + ions.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Qin Liu,Peipei Dang,Guodong Zhang,Hongzhou Lian,Ziyong Cheng,Guogang Li,Jun Lin
Mn2+-doped luminescent materials play a significant role in a variety of fields, including modern lighting, displays, and imaging. Mn2+ exhibits a broad and adjustable emission, hinging on the local environment of the crystal field and the interaction of the 3d5 electrons. However, it is still a challenge to realize the precise control of the emission of Mn2+ ions due to site-prior occupation in a specific lattice. Here, the formation of Mn–Mn dimers is proposed to be an effective strategy to design a novel red emission. Multimode emitters in Mn2+-activated AZn4(PO4)3 (A = K, Rb, and Cs) with unique [Zn4PO12] chains and [ZnOn] groups are observed to achieve regular green and unusual red emissions. KZn4(PO4)3:Mn2+ shows broad dual emissions at 542 and 608 nm, attributed to [MnO4] and [Mn2O7] dimers, respectively. While K is replaced with Rb and Cs, the Zn ions form [ZnO4] tetrahedra and [ZnO5] octahedra. RbZn4(PO4)3:Mn2+ exhibits a broad red emission at 618 nm, ascribing to [Mn2O7] and [Mn2O8] dimers. CsZn4(PO4)3:Mn2+ also displays a broad orange-red emission at 608–620 nm with increasing doping levels, deriving from energy transfer from [MnO5] to [Mn2O7] and [Mn2O8] dimers. This work provides a framework for creating novel red emissions from Mn2+-doped luminescent materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Tong Feng,Lijia Liang,Hui Zhou,Yuanlin Jin,Zhangwen Long,Dacheng Zhou,Xiaqing Jiang,Bitao Liu,Jianbei Qiu
The rapid advancement of near-infrared light source technology has positioned phosphor-converted light-emitting diodes (PC-LEDs) operating within the near-infrared spectrum at the forefront of interdisciplinary research, with extensive applications in biomedicine, food quality assessment, and agricultural monitoring. However, the development of light sources that cover the second near-infrared spectral window (NIR-II, 1000–1700 nm) continues to encounter significant technical challenges. Inspired by chemical unit co-substitution strategy, we successfully developed a broadband NIR-II phosphor designated as (Li 0.7 Mg 0.3 )(Ga 0.7 Mg 0.3 )TiO 4 :0.003Ni 2+ ((L 0.7 M 0.3 )(G 0.7 M 0.3 )T:0.003Ni 2+ ) through [Mg 2+ -Mg 2+ ] dual-site substitution in orthorhombic LiGaTiO 4 (LGT) normal spinel. This co-substitution strategy resulted in an impressive enhancement of the internal quantum efficiency by 29.77 %–64.8 %, while maintaining thermal stability without significant attenuation at elevated temperature. To validate its practical utility, we fabricated prototype for a NIR phosphor-converted LED by integrating (L 0.7 M 0.3 )(G 0.7 M 0.3 )T:0.003Ni 2+ a commercial 340 nm chip. The resulting device demonstrates promising potential for applications in food safety inspection and deep-tissue infrared imaging. This work provides a perspective for designing broadband high-efficiency NIR-II phosphors via modulation of crystal field environment.
研究领域:
材料科学
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光学工程
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·
IF 3.8
Zheng Gong,Yufei Gong,Junhui Hao,Zeyang Jang,Jiawei Yan,Tianle Bai,Yudong Xiao,Chun Wang
Near-infrared long-afterglow nanomaterials hold significant potential in nanomedicine platforms, including targeted drug delivery, precise imaging, and immunotherapy. Improving the particle size distribution and reducing the nanoparticle size to enhance biocompatibility are crucial. Due to the small size effect, reducing the nanoparticle size and improving uniformity typically lead to a decrease in afterglow performance. In this study, near-infrared long-afterglow nanoparticles, Zn 2 Ga 2.98 − x Ge 0.75 O 8 :Cr 3+ 0.02 ,Sm 3+ x ( x = 0, 0.02, 0.04, 0.06, 0.08) (ZGGO:Cr 3+ ,Sm 3+ x ), were synthesized using the Sm 3+ ion doping strategy at varying doping concentrations. This work reveals how cation substitution simultaneously affects the nanoparticle size and enhances the near-infrared long-afterglow luminescent performance. The Sm 3+ ion doping overcame the increased surface defects caused by the reduced particle size, while simultaneously improving the number of effective luminescent centers by modifying the crystal field environment around the luminescent center. The afterglow intensity and duration of ZGGO:Cr 3+ ,Sm 3+ x nanoparticles were significantly enhanced. The study shows that Sm 3+ ion doping effectively reduces the size of ZGGO:Cr 3+ ,Sm 3+ x nanoparticles while extending the near-infrared long-afterglow time by modulating trap depth, the interaction between traps and excited-state energy levels, and the competition between thermal activation and tunneling processes.
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产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2023
·Vol. 106
·期 11
·7069-7077
·
IF 3.9
Xiaomeng Yin,Ming Qiang,Hui Lin,Dawei Zhang,Ruijin Hong,Zhaoxia Han
In this work, we fabricated a novel spinel-type phosphor material MgAl 2− x Ga x O 4 doped with Cr 3+ by the high-temperature solid-state sintering method. The crystal field environment of the spinel was tuned by replacing the Al ions with Ga 3+ ions of different concentrations. The cell volume and D q / B gradient increase from 2.82 to 2.62 with increasing Ga 3+ ion doping concentration. This also implies a gradual decrease in the field strength of the crystal. Based on this, the excitation spectra of MgAl 1.995− x Ga x O 4 :0.5%Cr 3+ phosphors yield a redshift. Increasing the Ga 3+ ion doping concentration also improves the emission intensity and thermal stability of the phosphors, and the emission intensity of the Ga 3+ -doped phosphors is significantly increased. For a Ga/Al ratio of 1, the thermal stability of the phosphor emission is optimal. The emission intensity at 140°C can maintain 76% of the emission intensity at room temperature, indicating that appropriate Ga 3+ ion doping can improve the emission efficiency and thermal stability of the phosphors.
研究领域:
材料科学
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光学
·
荧光粉技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）