分子导向对氧化物界面的侧面和界面电子转移的影响
Quentin Loague1, Niklas D Keller1, Andressa V Müller2
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
ACS applied materials & interfaces
|July 7, 2023
概括
带有两种4,4'-(CO2H) 2-2,2'-双氨酸 (dcb) 连接体的敏化剂通过改善表面方向和电子转移动力学来优化染料敏化太阳能电池 (DSSC). 这导致DSSC的性能提高.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 太阳能光伏发电是如何实现的
背景情况:
- 基于的分子染料,特别是具有cis-[Ru(LL) ((dcb) ((NCS) 2结构的分子染料,是染料敏感太阳能电池 (DSSC) 的关键敏感剂.
- 4,4'-(CO2H) 2-2,2'-二氧化 (dcb) 连接体的数量影响着染料在电极表面的定和电子特性.
研究的目的:
- 研究以为基础的敏感剂中DCb配体的数量如何影响DSSC中的定,表面方向和界面电子转移动力学.
- 为了确定传感器结构对电子转移动态和整体DSSC性能的影响.
主要方法:
- 在ITO和TiO2纳米晶体薄膜上合成和定五种敏感剂 (三种含有两种DCB连接体,两种含有一种DCB连接体).
- 密度函数理论 (DFT) 计算以建模传感器-表面相互作用和距离.
- 电化学测量以研究介面电子转移动力学作为驱动力的函数,使用马库斯-格里希尔理论进行分析.
- 测量表面定传感器之间的横向自我交换电子传输速率.
主要成果:
- 带有两个dcb连接体的敏感剂在氧化物表面和Ru金属中心之间的距离 (∼1.6 Å) 比带有一个dcb连接体的敏感剂要小.
- 电子合矩阵元素 (Hab) 在0.23到0.70厘米-1之间,表明非adiabatic电子转移.
- 对于具有两个dcb连接体 (0.400.55 eV) 的敏感体,重组能量 (λ) 通常小于具有一个 (0.630.66 eV) 的敏感体.
- 侧面"跳孔"电子转移在具有两个dcb连接体的感应器中不存在,但在具有一个感应器中存在.
结论:
- 在DSSC中,dcb连接体的数量显著影响传感器方向和界面电子转移动力学.
- 带有两个dcb配体的敏感器由于优化的表面定和抑制的电荷重组路径而表现出卓越的性能.
- 这些发现突出了分子设计在优化高效染料敏感化太阳能电池的传感器性能方面的关键作用.
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