电化学同位素效应和同位素的分离
Jay R Black1, Grant Umeda, Bruce Dunn
1Institute for Geophysics and Planetary Physics, University of California, Los Angeles, California 90095, USA.
Journal of the American Chemical Society
|July 8, 2009
概括
来自碳酸溶液的电沉积产生同位素轻金属. 同位素效应的大小取决于应用的超电位,在近平衡条件下最大.
科学领域:
- 电化学 电化学 电化学
- 同位素地球化学 同位素地球化学
- 材料科学 材料科学 材料科学
背景情况:
- 电化学沉积是生产纯金属的关键过程.
- 在电化学系统中同位素分离尚未完全理解.
- 的独特特性使其同位素行为引起了人们的兴趣.
研究的目的:
- 为了研究在沉积过程中的电化学同位素效应.
- 在这个系统中确定控制同位素分离的因素.
- 将实验结果与理论预测进行比较.
主要方法:
- 从碳酸溶液中电化学沉积.
- 测量沉积的同位素组成.
- 变化应用过电势来研究其对分离的影响.
- 对复合体和金属的分区函数比率的计算.
主要成果:
- 观察到一个显著的电化学同位素效应,产生同位素轻.
- 同位素分离的程度是由应用的过电位直接控制的.
- 最大分离发生在最接近电化学平衡的超电位.
- 分区函数比率的理论计算与实验结果一致.
结论:
- 的电化学沉积表现出很大的同位素效应.
- 超电位是控制电沉积过程中同位素分离的关键参数.
- 理论模型支持平衡分数的实验观测.
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