Wang Anran, Kang Yifei, Hou Chunqing, Li Rong, Song Yilong, Dong Qingfeng
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.
Sci Bull (Beijing). 2023 Jun 15;68(11):1153-1161. doi: 10.1016/j.scib.2023.05.005. Epub 2023 May 11.
The miscibility between active layer donors (D) and acceptors (A) is a key factor impeding the development of organic photovoltaics (OPVs) toward higher performance and large-area production. In this study, melt blending crystallization (MBC) was used to accomplish molecular-level blending and highly oriented crystallization in bulk heterojunction (BHJ) films realized by a scalable blade coating process, which increased the D/A contact area and provided sufficient exciton diffusion and dissociation. At the same time, the highly organized and balanced crystalline nanodomain structures permitted dissociated carriers to be efficiently transmitted and collected, resulting in significantly enhanced short-circuit current density, fill factor, and efficiency of the device by means of optimum melting temperature and quenching rates. The method can be simply incorporated into current efficient OPV material systems and achieve a device performance comparable to the best values. The blade-coating-processed PM6/IT-4F MBC devices achieved an efficiency of 13.86% in a small-area device and 11.48% in a large-area device. A power conversion efficiency (PCE) of 17.17% was obtained in PM6:BTP-BO-4F devices, and a PCE of 16.14% was acquired in PM6:Y6 devices.
活性层供体（D）与受体（A）之间的混溶性是阻碍有机光伏（OPV）向更高性能和大面积生产发展的关键因素。在本研究中，采用熔体共混结晶（MBC）在通过可扩展刮刀涂布工艺制备的本体异质结（BHJ）薄膜中实现分子水平的共混和高度取向的结晶，这增加了D/A接触面积，并提供了足够的激子扩散和解离。同时，高度有序且平衡的结晶纳米域结构使离解的载流子能够有效地传输和收集，通过优化熔融温度和淬火速率，显著提高了器件的短路电流密度、填充因子和效率。该方法可简单地应用于当前高效的OPV材料体系，并实现与最佳值相当的器件性能。刮刀涂布工艺制备的PM6/IT-4F MBC器件在小面积器件中的效率为13.86%，在大面积器件中的效率为11.48%。PM6:BTP-BO-4F器件的功率转换效率（PCE）为17.17%，PM6:Y6器件的PCE为16.14%。
