铈(Ⅲ)和铈(Ⅳ)的溶液动力学探究

Molecular Dynamics of Tri/Tetra-Valent Cerium in Aqueous Solution

铈作为重要的稀土元素,在众多领域起着关键作用,一方面源于铈元素独特的化学性质,另一方面源于铈除了镧系元素常见的正三价外,还具有稳定的正四价,易于从化学性质极为相似的镧系元素中提取。近年来,Ce^(3+)/Ce^(4+)在水溶液中较高的氧化还原电势引起相关学者关注,基于此开发的锌铈液流电池具有广阔的应用前景,但微观机制和电极优化仍需研究。本文通过运用分子模拟方法,探究了Ce^(3+)和Ce^(4+)分别在水中的溶液动力学行为,从配位构型、离子扩散、配位水交换和溶剂化自由能等方面解释了两者的共性和区别,为铈元素的基础溶液行为和应用推广提供理论支持。

As a vital rare earth element,cerium(Ce)plays a key role in many fields.This is due to the unique chemical properties of cerium,and easy extraction from other rare earth elements with stable tetravalent form.In recent years,the high redox potential of Ce^(3+)/Ce^(4+)pair in aqueous solution has attracted more attention of scientists.Applications based on this advantage,e.g.zinc-cerium flow battery has broad application prospects,but the deep mechanism remains unclear.This work simulates the dynamics of Ce^(3+)and Ce^(4+)in aqueous solution by classic molecular dynamics method,and explains the commonalities and differences between the two systems in terms of coordination configuration,ions diffusion,coordination water exchange and solvation free energy,aiming to provide the theoretical support for the basic solution behavior and further application of cerium.