稀土改性电化学储能电极材料的研究进展

Rare Earth Element Ion Modified Electrochemical Energy Storage Electrode Materials- A Short Review

稀土高值化利用是提升我国稀土资源附加值的重要途径,开拓稀土离子在电化学储能材料中的应用是稀土高值化利用的具体方案之一。综述了稀土离子在电化学储能电极材料应用中的最新研究进展,证明了稀土离子能够有效提升电极材料的电化学性能,同时分析了稀土离子在电化学反应中的作用机制,探讨了稀土离子的利用形式以及高效提升电化学性能的方式。从稀土离子掺杂、稀土离子包覆电极材料入手,具体介绍了稀土离子在稳定电极材料结构、改善电极材料电子电导率、离子扩散特性等中的作用。稀土离子的电负性和离子尺寸是调节锂离子电池和超级电容器电极材料性能的主要设计依据。希望充分利用我国稀土资源优势,提升我国在稀土电化学储能领域中的研究地位和原始创新能力。

This paper reviewed recent developments on rare earth elements used in electrode materials for electrochemical energy storage, i.e., lithium ion batteries and supercapacitors, electrochemical reaction mechanism of rare earth element ions, and the utilization forms of rare earth element ions for enhancing electrochemical performance. The effect of rare earth element ions on the stabilization of the electrode materials structure, the improvement of the electronic conductivity and the ion diffusion was represented. The electronegativity and ionic size of rare earth elements are two important parameters to affect the structure, activity, reactivity of traditional electrode materials because that the ionic sizes of rare earth element ions are greater than those of the transition metal ions, while the electronegativity of rare earth element ions is lower than that of transition metal ions. Moreover, the ionic electronegativity can affect the electrostatic interactions between ions, while the ionic radius can control steric effect between ions. Rare earth element ion doping and coating are two important routes to construct rare earth element modified transition metal oxide materials, which are often used in composite electrode materials.