在Na4Fe3(PO4) 2(P2O7) 阴极中的离子极化驱动缺陷工程:离子电池的快速充电和超长周期寿命
Yu-Jie Wang1, Zhen-Yi Gu2, Dong-Sheng Bai1
1School of Chemical Engineering, ocean and life science, Dalian University of Technology, Panjin, Liaoning, 124221, P.R. China.
Angewandte Chemie (International ed. in English)
|May 29, 2025
概括
木兴奋剂可以提高离子电池阴极性能. 这种缺陷工程策略提高了离子电池 (SIB) 的快速充电能力和长周期稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 固态化学 固态化学
背景情况:
- 离子电池 (SIB) 需要具有提高高速率性能和长周期稳定性的正极材料.
- 4Fe3(PO4)2(P2O7) (NFPP) 材料在平衡这些特性方面存在挑战.
研究的目的:
- 制定一个缺陷工程策略,以提高SIB中的NFPP阴极材料性能.
- 调查Bi3+兴奋剂对NFPP电子结构和Na+动态的影响.
主要方法:
- 试验合成和表征Bi3+兴奋剂的NFPP.
- 理论计算 (例如,DFT) 来分析电子结构和离子扩散.
- 半电池和全电池的电化学测试.
主要成果:
- 通过加强Bi-O键,Bi3+兴奋剂显著提高了NFPP晶体结构的稳定性.
- 兴奋剂优化带隙 (3.29至0.16 eV),促进Na+扩散,并引入储存的晶格缺陷.
- 优化的0.02Bi-NFPP阴极表现出快速充电 (在1°C下在31.6分钟内80%充电) 和卓越的循环稳定性 (20°C下在20,000个循环中保持86.9%).
- 一个带有硬碳阳极的全SIB在1C的200个循环后保持了95.5%的容量.
结论:
- 通过Bi3+兴奋剂进行离子极化驱动的缺陷工程是NFPP阴极材料的有效策略.
- 这种方法协同改善SIB的快速充电和超长周期寿命.
- 为设计用于储能的先进阴极材料提供了一条新途径.
相关概念视频
Batteries and Fuel Cells
A battery is a galvanic cell that is used as a source of electrical power for specific applications. Modern batteries exist in a multitude of forms to accommodate various applications, from tiny button batteries such as those that power wristwatches to the very large batteries used to supply backup energy to municipal power grids. Some batteries are designed for single-use applications and cannot be recharged (primary cells), while others are based on conveniently reversible cell reactions that...
P-N junction
A p-n junction is formed when p-type and n-type semiconductor materials are joined together. At the interface of the p-n junction, holes from the p-side and electrons from the n-side begin to diffuse into the opposite sides due to the concentration gradient. This diffusion of carriers leads to a region around the junction where there are no free charge carriers, known as the depletion region. The charge density within the depletion region for the n-side and p-side can be described by the...
Ionic Association
The ionic association is the association of oppositely charged ions in an electrolyte solution to form ion pairs. Bjerrum defined ion pairs as two oppositely charged ions whose electrostatic attraction exceeds the thermal energy of the system, typically expressed as 2kT. Electrostatic attraction depends on ionic charge, separation distance, and the dielectric constant of the medium. Thermal energy, represented by kT, reflects the tendency of ions to move independently due to molecular motion.
Electrochemical Systems
Electrochemical systems provide a fascinating insight into the dynamic interplay of charged species within various phases. One notable example is the interaction between a membrane permeable to K⁺ ions but not to Cl⁻ ions, separating an aqueous KCl solution from pure water. As K⁺ ions diffuse through the membrane, they generate net charges on each phase, leading to a potential difference between them.Similarly, when a piece of Zn is immersed in an aqueous ZnSO₄ solution, the Zn metal, composed...
The Electrical Double Layer
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...
Imperfections in Crystal Structure: Stoichiometric Point Defects
Schottky defects arise when some lattice points in a crystal, such as those in NaCl, remain unoccupied, creating lattice vacancies without disturbing the overall electrical neutrality of the crystal. This defect is common in ionic crystals where the positive and negative ions are similar in size, as seen in sodium chloride and cesium chloride. The presence of Schottky defects enables the crystal to conduct electricity to a small extent through an ionic mechanism. Electric fields cause nearby...


