导向依赖的非对称载荷运输机制在包括光系统I在内的道交叉点
Olga E Castañeda Ocampo1,2, Pavlo Gordiichuk2, Stefano Catarci2
1†Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|June 10, 2015
概括
像光系统I (PSI) 这样的光活性蛋白在自组装单层 (SAM) 中表现出不对称的电流传输. 这种对称性对于生物灵感太阳能电池至关重要,归因于PSI.
科学领域:
- 生物物理学的生物物理.
- 材料科学 材料科学 材料科学
- 可再生能源可再生能源是可再生能源.
背景情况:
- 光活性蛋白,特别是光系统I (PSI),越来越多地用于生物启发的电化学和太阳能电池技术.
- 了解基于蛋白质的电子设备中的电荷传输机制对于优化其性能至关重要.
- 自组装单层 (SAM) 为定位蛋白质和研究其电子性质提供了一个平台.
研究的目的:
- 测量和分析整个光系统I (PSI) 蛋白质复合体在自组装单层 (SAM) 中电流传输的不对称性.
- 调查由总监SAMS引发的优先PSI导向在收费运输方面的作用.
- 确定电荷传输机制,并确定PSI SAM中电流不对称的来源.
主要方法:
- 制造具有两个不同的导向SAM的功能超平面黄金基板,以诱导优先的PSI导向.
- 在面向的PSI SAM中测量电流传输,使用大面积的欧特克 Ga-In (EGaIn) 和单复合导探原子力显微镜 (CP-AFM).
- 取决于温度的电流-电压 (I-V) 测量,以阐明电荷传输机制.
主要成果:
- 对于面向PSI的SAM,EGaIn和CP-AFM技术都产生了可比的运输特性.
- 在±0.1到±1.0V偏差之间没有观察到电流的显著温度依赖,支持道作为主要的运输机制.
- 观察到的导电不对称性并非归因于PSI电子传输链内的热激活过程或放松.
结论:
- 该研究证实,道是PSI SAM中占主导地位的载荷运输机制.
- 电流传输中的显著不对称性主要是由于PSI复合体固有的大,净双极矩.
- 这些发现为生物电子设备和太阳能转换中的应用提供了对PSI电子性能的关键见解.
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