当前位置：
X-MOL 学术
›
Inorg. Chem.
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Monoclinic α-Na2FePO4F with Strong Antisite Disorder and Enhanced Na+ Diffusion
Inorganic Chemistry ( IF 4.3 ) Pub Date : 2020-11-02 , DOI: 10.1021/acs.inorgchem.0c01961 Maria A. Kirsanova 1 , Alexey S. Akmaev 2 , Dmitry A. Aksyonov 2 , Sergey V. Ryazantsev 2 , Victoria A. Nikitina 2 , Dmitry S. Filimonov 3 , Maxim Avdeev 4 , Artem M. Abakumov 2
Inorganic Chemistry ( IF 4.3 ) Pub Date : 2020-11-02 , DOI: 10.1021/acs.inorgchem.0c01961 Maria A. Kirsanova 1 , Alexey S. Akmaev 2 , Dmitry A. Aksyonov 2 , Sergey V. Ryazantsev 2 , Victoria A. Nikitina 2 , Dmitry S. Filimonov 3 , Maxim Avdeev 4 , Artem M. Abakumov 2
Affiliation
|
A new monoclinic α-polymorph of the Na2FePO4F fluoride-phosphate has been directly synthesized via a hydrothermal method for application in metal-ion batteries. The crystal structure of the as-prepared α-Na2FePO4F studied with powder X-ray and neutron diffraction (P21/c, a = 13.6753(10) Å, b = 5.2503(2) Å, c = 13.7202(8) Å, β = 120.230(4)°) demonstrates strong antisite disorder between the Na and Fe atoms. As revealed with DFT-based calculations, α-Na2FePO4F has low migration barriers for Na+ along the main pathway parallel to the b axis, and an additional diffusion bypass allowing the Na+ cations to go around the Na/Fe antisite defects. These results corroborate with the extremely high experimental Na-ion diffusion coefficient of (1–5)·10–11 cm2·s–1, which is 2 orders of magnitude higher than that for the orthorhombic β-polymorph ((5–10)·10–13 cm2·s–1). Being tested as a cathode material in Na- and Li-ion battery cells, monoclinic α-Na2FePO4F exhibits a reversible specific capacity of 90 and 80 mAh g–1, respectively.
中文翻译：
单斜晶α-的Na 2的FePO 4 f控制强障碍反位和增强型的Na +扩散
通过水热法直接合成了Na 2 FePO 4 F氟化物磷酸盐的单斜α-多晶型物，并将其应用于金属离子电池。的晶体结构所制备的α-的Na 2的FePO 4 ˚F研究了粉末X射线和中子衍射（P 2 1 / ç，一个= 13.6753（10）A，b = 5.2503（2）埃，c ^ = 13.7202 （8）Å，β= 120.230（4）°）表明Na和Fe原子之间存在强烈的反位错。与基于DFT的计算显示，α-的Na 2的FePO 4 F具有的Na低迁移障碍+沿着平行于b轴的主要路径，以及一个额外的扩散旁路，允许Na +阳离子绕过Na / Fe反位缺陷。这些结果与（1–5）·10 –11 cm 2 ·s –1的极高的Na离子扩散系数实验相符，该扩散系数比正交β-多晶型物高（2（5–10 ）·10 –13 cm 2 ·s –1）。被测试为在NA-阴极材料和锂离子电池单元，单斜晶α-的Na 2的FePO 4 ˚F表现出90和80毫安g的可逆比容量-1，分别。
更新日期：2020-11-16
中文翻译：
单斜晶α-的Na 2的FePO 4 f控制强障碍反位和增强型的Na +扩散
通过水热法直接合成了Na 2 FePO 4 F氟化物磷酸盐的单斜α-多晶型物，并将其应用于金属离子电池。的晶体结构所制备的α-的Na 2的FePO 4 ˚F研究了粉末X射线和中子衍射（P 2 1 / ç，一个= 13.6753（10）A，b = 5.2503（2）埃，c ^ = 13.7202 （8）Å，β= 120.230（4）°）表明Na和Fe原子之间存在强烈的反位错。与基于DFT的计算显示，α-的Na 2的FePO 4 F具有的Na低迁移障碍+沿着平行于b轴的主要路径，以及一个额外的扩散旁路，允许Na +阳离子绕过Na / Fe反位缺陷。这些结果与（1–5）·10 –11 cm 2 ·s –1的极高的Na离子扩散系数实验相符，该扩散系数比正交β-多晶型物高（2（5–10 ）·10 –13 cm 2 ·s –1）。被测试为在NA-阴极材料和锂离子电池单元，单斜晶α-的Na 2的FePO 4 ˚F表现出90和80毫安g的可逆比容量-1，分别。
京公网安备 11010802027423号