‡Department of Materials Science and Engineering, Stanford University, Palo Alto, California 94305-4034, United States.
ACS Appl Mater Interfaces. 2015 May 13;7(18):9957-64. doi: 10.1021/acsami.5b02202. Epub 2015 Apr 30.
Quantifying cohesion and understanding fracture phenomena in thin-film electronic devices are necessary for improved materials design and processing criteria. For organic photovoltaics (OPVs), the cohesion of the photoactive layer portends its mechanical flexibility, reliability, and lifetime. Here, the molecular mechanism for the initiation of cohesive failure in bulk heterojunction (BHJ) OPV active layers derived from the semiconducting polymer poly(3-hexylthiophene) [P3HT] and two monosubstituted fullerenes is examined experimentally and through molecular-dynamics simulations. The results detail how, under identical conditions, cohesion significantly changes due to minor variations in the fullerene adduct functionality, an important materials consideration that needs to be taken into account across fields where soluble fullerene derivatives are used.
量化薄膜电子器件中的内聚性并理解其断裂现象，对于改进材料设计和加工标准是必要的。对于有机光伏（OPV）器件而言，光活性层的内聚性预示着其机械灵活性、可靠性和寿命。在这里，通过实验和分子动力学模拟研究了源自半导体聚合物聚（3-己基噻吩）[P3HT]和两种单取代 fullerene 的本体异质结（BHJ）OPV 活性层中内聚性失效起始的分子机制。结果详细说明了在相同条件下，由于富勒烯加成物官能度的微小变化，内聚性会发生显著变化，这是在使用可溶性富勒烯衍生物的各个领域都需要考虑的重要材料因素。
