Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seoul 120-749, Korea.
Macromol Rapid Commun. 2011 Jul 15;32(14):1066-71. doi: 10.1002/marc.201100132. Epub 2011 May 3.
Spin-coating a mixture solution of P3HT and PCBM on a cold substrate largely enhanced the power conversion efficiency (PCE) of the bulk heterojunction (BHJ) solar cells. This concept was based on the abrupt decrease in the solubility of P3HT as solution temperature decreased. The selective precipitation of P3HT on the PEDOT:PSS-coated cold substrate facilitated a desirable rich composition of P3HT at the interface with the PEDOT:PSS layer. The high crystallinity of P3HT suppressed the movement of PCBM during thermal annealing, preventing aggregation of PCBM. The morphological excellence of the pristine film gave a comparable PCE to that made by the conventional fabrication process. After thermal annealing, the device made via coating on a cold substrate showed above 30% increase in PCE from the BHJ solar cells made by the conventional method.
将 P3HT 和 PCBM 的混合物溶液旋涂在冷基底上，极大地提高了体异质结（BHJ）太阳能电池的功率转换效率（PCE）。这一概念基于溶液温度降低时 P3HT 溶解度的急剧下降。在 PEDOT:PSS 涂层的冷基底上选择性沉淀 P3HT，有利于在与 PEDOT:PSS 层的界面处形成富 P3HT 的理想组成。P3HT 的高结晶度抑制了 PCBM 在热退火过程中的运动，防止了 PCBM 的聚集。原始薄膜的优异形态使 PCE 与传统制造工艺相当。经过热退火后，通过在冷基底上涂层制备的器件的 PCE 比通过传统方法制备的 BHJ 太阳能电池提高了 30%以上。
