在层层自组装的氧化还原聚电解质薄膜中,多南的选择性.
Ernesto J Calvo1, Alejandro Wolosiuk
1INQUIMAE, Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Pabellón 2 Ciudad Universitaria, AR-1428 Buenos Aires, Argentina. calvo@q1.fcen.uba.ar
Journal of the American Chemical Society
|July 11, 2002
概括
氧化电解质多层呈现可调节的电化学特性. 由电化学石英晶体微平衡监测的离子和溶剂交换取决于薄膜电荷,pH值和电解质度,影响氧化还原潜力.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
背景情况:
- 层层沉积 (LBL) 是一种多功能技术,用于组装氧化还原聚电解质多层.
- 基于的氧化还原聚合物对于电化学应用至关重要,但它们在多层膜中的行为需要详细调查.
- 了解这些膜内的离子和溶剂运输对于控制它们的电化学反应至关重要.
研究的目的:
- 为了研究使用LBL沉积组装的氧化还原聚电解质多层的电化学行为.
- 探索电解质度,pH值和最外层电荷对Os{II}/Os{III}对的氧化还原潜力的影响.
- 用电化学石英晶微平衡 (EQCM) 来描述氧化还原切换期间的离子和溶剂交换.
主要方法:
- 层层沉积 (LBL) 用于组装多层薄膜,使用与Os (bpy) (ClPyCHO) (PAH-Os) 和阳离子聚乙烯硫酸盐 (PSS) 或聚乙烯硫酸盐 (PVS) 修改的阴离子聚乙烯胺.
- 循环电压测量,以确定Os (II) /Os (III) 对的正式氧化还原潜力.
- 电化学石英晶体微平衡 (EQCM) 用于监测与离子和溶剂交换相关的质量变化.
主要成果:
- Os{II}/Os{III}对的正式氧化还原潜力对最外层的电荷,电解质度和pH敏感.
- 在较低的离子强度下,多南选择性控制离子排斥,这取决于薄膜电荷和pH值.
- 在高电解质度下,发生多南分解,氧化还原潜力接近溶液值. 在选择性和多南分解条件下,EQCM揭示了不同的离子和水交换机制.
结论:
- 氧化多电解质多层通过控制组装条件和环境,提供可调节的电化学特性.
- 唐南平衡原理解释了电解质度低的离子运输,而高度导致膜膨胀和改变的离子运输.
- EQCM是一个强大的工具,用于阐明氧化还原切换,离子流和多电解质多层溶剂吸收之间的复杂相互作用.
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