显著的基与基替代剂对正方体染料固态结构,载体流动性和批量异质连接太阳能电池效率的影响
Diego Bagnis1, Luca Beverina, Hui Huang
1Department of Chemistry and the Argonne-Northwestern Solar Energy Research Center, Northwestern University, Evanston, Illinois 60208, USA.
Journal of the American Chemical Society
|March 9, 2010
概括
介绍有机太阳能电池的两种新型正方形染料. 取代的染料显著提高了电荷传输和功率转换效率 (PCE),在溶液加工设备中达到2%以上的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:
- 斯克瓦莱因染料是太阳能电池应用的有希望的有机半导体.
- 优化分子结构是改善电荷传输和设备性能的关键.
研究的目的:
- 合成和描述两种具有不同侧链 (n-hexyl与n-hexenyl) 的新方形染料.
- 研究侧链修改对固态包装,电荷传输和有机光伏 (OPV) 性能的影响.
主要方法:
- 用n-hexyl和n-hexenyl替代剂合成四角色素染料.
- 使用合成的染料制造大量异质连接 (BHJ) 有机太阳能电池.
- 细膜形态的表征,电荷传输特性 (孔移动性) 和设备性能 (功率转换效率 - PCE).
主要成果:
- 与n-hexyl衍生物 (squaraine 1) 相比,用n-hexenyl替代的方染料 (squaraine 2) 呈现出更紧的固态结构.
- 方形2薄膜中的孔移动性大约是方形1的五倍,而不是方形1.
- 基于squaraine 2的BHJ OPV设备的功率转换效率 (PCE) 大约是使用squaraine 1的功率转换效率的两倍.
- 环境溶液处理设备的PCE超过了2%,这对基于方的太阳能电池来说是一个显著的进步.
结论:
- 在n-hexenyl链中的终端双键显著影响固态包装和充电运输.
- 结构修改,即使是微小的修改,也可以大大提高OPV的性能.
- 这些发现为开发基于正方体化学的高性能溶液加工有机太阳能电池铺平了道路.
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