Journal of Energy Chemistry
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2023
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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
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电化学
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能源存储
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无机化学
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固态化学
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电池技术
✓ 已验证
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
JOURNAL OF LUMINESCENCE
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2018
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IF 2.732
Qinghua Yang,Benxue Jiang,Shuilin Chen,Yiguang Jiang,Pande Zhang,Jun Wang,Shiqing Xu,Long Zhang
Al 2 O 3 : Er 3+ /Yb 3+ transparent ceramics codoped with Zn 2+ ions with intense upconversion and near infrared emission were prepared by conventional solid-state reaction and vacuum and hot isostatic pressing sintering. The effects of Zn 2+ incorporation to the structure, transparent, upconversion and NIR luminescence were discussed in detail. The as prepared Al 2 O 3 ceramics exhibited a total transmittance of ~ 75% in infrared regions (800–3300 nm) and ~ 50% in visible regions (500–800 nm). Under the excitation of a 980 nm laser diode , the as prepared Al 2 O 3 ceramics displayed two tense upconversion emission peaks of a green one centered at 550 nm and a red one centered at 660 nm and a tense near infrared emission peak centered at 1.532 µm, characteristic of Er 3+ emission. Compared with Er 3+ /Yb 3+ doped only, Zn 2+ codoped Al 2 O 3 :Er 3+ /Yb 3+ transparent ceramics showed higher upconversion and near infrared emission of ~ 11 times and ~ 4 times, respectively. The enhancement mechanism due to incorporation of Zn 2+ ions was also discussed in detail.
研究领域:
材料科学
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光学材料
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无机非金属材料
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发光材料
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陶瓷工程
✓ 已验证
DOI
高影响因子
OPTICS AND LASER TECHNOLOGY
·
2016
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IF 1.879
Rong Chen,Ying Tian,Bingpeng Li,Feifei Huang,Caizhi Wang,Xufeng Jing,Junjie Zhang,Shiqing Xu
Nd 3+ /Ho 3+ co-doped silicate-germanate glass has been synthesized by high temperature melt-quenching method. Near infrared emission centered at 2 µm has been successfully obtained by incorporating Nd 3+ and Ho 3+ in present glass. The Judd-Ofelt intensity parameters Ω t (t=2, 4, 6), and radiative properties of Ho 3+ were calculated and discussed by using the Judd-Ofelt theory. The energy transfer processes and luminescence properties of Nd 3+ /Ho 3+ co-doped glasses were analyzed pumped by a conventional 808 nm laser diode . Desirable spectroscopic characteristics indicates that Nd 3+ /Ho 3+ co-doped silicate-germanate glass might be a good alternative matrix for 2 µm band mid-infrared laser.
研究领域:
光学材料
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无机非金属材料
·
光子学
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激光技术
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固体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）