Phase-field modeling of transport-limited electrolysis in solid and liquid states
Phase-field modeling of transport-limited electrolysis in solid and liquid states
复制标题
固态和液态输运限制电解的相场建模
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
David Dussault
中科院分区：
文献类型：
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作者：
W. Pongsaksawad;A. Powell;David Dussault
建立了电化学界面动力学的相场模型，研究了在快速电荷再分配条件下二维和三维输运限制电解过程中阴极形状和拓扑结构的变化.对Fe-FeO二元体系进行了实例研究。该模型的稳定性行为与电沉积过程中小振幅正弦扰动的线性稳定性理论相一致。当没有对流时，高电场和低表面张力导致阴极界面不稳定，导致枝晶生长，枝晶破碎成粉末。当电极和电解质是低粘度流体时，流动提供了用于稳定界面的附加机制。根据量纲分析和模型结果，推导出一个新的基于施密特数的稳定性判据。对于一个不稳定的阴极界面，流光形态（液体枝晶）观察到在二维和三维。将该二元模型推广到三元体系，并以Ti-Mg-Cl体系为例进行了计算。一维和二维三元模拟显示定性正确的接口运动和电势行为。
A phase-field model of electrochemical interface dynamics is developed to study cathode shape and topology change in transport-limited electrolysis in two and three dimensions under conditions of rapid charge redistribution. A case study for the binary model is carried out for an Fe-FeO system. Stability behavior of the model is in good agreement with linear stability theory for small amplitude sinusoidal perturbation in electrodeposition. When there is no convection, a high electric field and low surface tension cause the cathode interface to be unstable, leading to growth of dendrites which break into powders. When the electrodes and electrolyte are low-viscosity fluids, flow provides an additional mechanism for stabilizing the interface. A new stability criterion for this liquid situation based on the Schmidt number is derived from dimensional analysis and model results. For an unstable cathode interface, a streamer morphology (liquid dendrites) is observed in two and three dimensions. This binary model is extended to a ternary system and a representative case is carried out for the Ti-Mg-Cl system. One- and two-dimensional ternary simulations show qualitatively correct interface motion and electrical potential behavior.