通过甲基替代高性能有机太阳能电池,精确调节重组能量
Li Chen1, Chaoyue Zhao1, Joshua Yuk Lin Lai1
1Department of Chemistry and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, The Hong Kong University of Science and Technology, Hong Kong, 999077, P. R. China.
概括
使用甲基和基组设计新的昆素受体,可以最大限度地减少有机太阳能电池 (OSC) 的能量损失. BQx-MeCl通过减少重组能量和改善电荷传输,实现了19.2%的功率转换效率 (PCE).
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 太阳能光伏发电是如何实现的
背景情况:
- 高效的充电传输和尽量减少能源损失对于高性能有机太阳能电池 (OSC) 至关重要.
- 分子设计在控制材料特性和设备效率方面发挥着关键作用.
研究的目的:
- 设计和合成基于甲基和素替代物的新型昆素电子受体.
- 系统地研究这些替代物对重组能量 (λ) 和膜形态学的影响.
- 在OSC中,将分子结构与电荷传输特性和功率转换效率 (PCE) 相对应.
主要方法:
- 基于昆素的电子受体 (BQx-MeF,BQx-MeCl,BQx-MeBr) 的合成.
- 量子化学计算以确定重组能量 (λ) 并了解电子性质.
- 二元和三元有机太阳能电池 (OSC) 的制造和表征.
- 测量电荷载体流动性和功率转换效率 (PCE).
主要成果:
- 甲基化被发现通过限制结构放松,有效地降低了重组能量 (λ).
- BQx-MeCl表现出抑制的非辐射重组能量损失 (ΔEnr) 和平衡的电子/孔流动性.
- 在使用BQx-MeCl.Cl的二进制OSC设备中,实现了19.2%的功率转换效率 (PCE).
- 在优化的三元OSC中,由于增强的分子堆叠和膜形态,BQx-MeCl进一步提高了PCE至19.6%.
结论:
- 分子设计,特别是降低重组能量 (λ),是最大限度地减少OSC中的能量损失的关键策略.
- BQx-MeCl 是一种有前途的电子受体材料,用于开发高效的有机太阳能电池.
- 优化的分子堆叠和薄膜形态通过减少陷辅助重组,大大提高了设备性能.
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