ELECTROCHEMICAL ASPECTS OF THE GENERATION OF RAMIFIED METALLIC ELECTRODEPOSITS
ELECTROCHEMICAL ASPECTS OF THE GENERATION OF RAMIFIED METALLIC ELECTRODEPOSITS
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DOI：
10.1103/physreva.42.7355
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发表时间：
1990-12-15
影响因子：
2.9
通讯作者：
CHAZALVIEL, JN
中科院分区：
文献类型：
--
作者：
CHAZALVIEL, JN
在薄矩形电解槽的几何形状中，考虑了在高电场下从稀盐溶液中通过电沉积形成分支金属沉积物的生长。在稀电解质的情况下，离子运动的方程已经在一维（1D）和2D近似的数值和解析求解。据发现，分枝生长是一个直接的后果，在阴极附近的阴离子耗尽后的空间电荷的创建。预测分枝存款的前面推进的速度正好等于在所施加的电场中的负离子的速度。这种空间电荷的存在下，提前增长的前沿是与潜在的下降Δ V。在2D的情况下的方程的分辨率表明，致密的平行形态的存款也很自然地从存在的空间电荷在附近的灯丝尖端。平均细丝间距和侧支倾斜角可以直接与Δ V和所施加的电场的值相关。产生空间电荷的机制也适用于任何涉及两种载流子导电的物理系统，只要其中一种载流子表现出阻断-接触特性。
The growth of ramified metallic deposits by electrodeposition from dilute salt solutions and in a high electric field has been considered in the geometry of a thin rectangular cell. The equations governing ion motion in the case of a dilute electrolyte have been solved numerically and analytically in a one-dimensional (1D) and a 2D approximation. It is found that ramified growth is a direct consequence of the creation of a space charge upon anion depletion in the vicinity of the cathode. The front of the ramified deposit is predicted to advance at a speed just equal to the velocity of the anions in the applied electric field. The presence of this space charge ahead of the growing front is associated with a potential drop delta-V. Resolution of the equations in the 2D case shows that the dense-parallel morphology of the deposit also results quite naturally from the existence of a space charge in the vicinity of the filament tips. The average filament spacing and sidebranch tilting angle can be directly related to the values of delta-V and of the applied electric field. The mechanism giving rise to the space charge will apply as well to any physical system involving electric conduction with two types of carriers, if one of them exhibits blocking-contact characteristics.