Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, USA.
Langmuir. 2010 Apr 6;26(7):4602-6. doi: 10.1021/la100292u.
We report the formation and characterization of one-dimensional chemical composition gradients of CdS on Au surfaces using bipolar electrodeposition. When an external electric field is applied across an electrically floating Au electrode immersed in a bipolar electrochemical cell, a position-dependent interfacial potential difference is generated along the length of the Au. This potential gradient can be used to induce variations of chemical composition within thin films electrodeposited onto the Au bipolar electrode (BPE). Thin films formed by bipolar electrodeposition represent continuous one-dimensional solid-state material libraries and were screened using resonance Raman microscopy and Auger electron spectroscopy. As predicted from simple thermodynamic considerations, we observed three distinct deposition zones scanning from the cathodic pole to the midpoint of the BPE: (i) CdS+Cd, (ii) stoichiometric CdS, and (iii) elemental S. Bipolar electrodeposition can be used to generate material libraries rapidly and without direct electrical contact to the substrate using extremely simple instrumentation.
我们使用双极电沉积法报告了在 Au 表面上形成和表征一维 CdS 化学组成梯度。当将外部电场施加到浸入双极电化学电池中的电浮 Au 电极时，会沿 Au 的长度产生位置相关的界面电势差。这个电势梯度可用于诱导在 Au 双极电极（BPE）上电沉积的薄膜中的化学组成变化。通过双极电沉积形成的薄膜代表连续的一维固态材料库，并使用共振拉曼显微镜和俄歇电子能谱进行筛选。根据简单的热力学考虑，我们观察到从阴极到 BPE 中点的三个不同的沉积区：（i）CdS+Cd，（ii）化学计量比 CdS 和（iii）元素 S。双极电沉积可以使用非常简单的仪器快速生成材料库，而无需直接与衬底接触。
