Li Saimeng, Gao Mengyuan, Zhou Kangkang, Li Xin, Xian Kaihu, Zhao Wenchao, Chen Yu, He Chunyong, Ye Long
School of Materials Science and Engineering, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300350, China.
Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing, 210037, China.
Adv Mater. 2024 Feb;36(8):e2307278. doi: 10.1002/adma.202307278. Epub 2023 Dec 8.
Organic solar cells (OSCs) have potential for applications in wearable electronics. Except for high power conversion efficiency (PCE), excellent tensile properties and mechanical stability are required for achieving high-performance wearable OSCs, while the present metrics barely meet the stretchable requirements. Herein, this work proposes a facile and low-cost strategy for constructing intrinsically stretchable OSCs by introducing a readily accessible polymer elastomer as a diluent for all-polymer photovoltaic blends. Remarkably, record-high stretchability with a fracture strain of up to 1000% and mechanical stability with elastic recovery >90% under cyclic tensile tests are realized in the OSCs active layers for the first time. Specifically, the tensile properties of best-performing all-polymer photovoltaic blends are increased by up to 250 times after blending. Previously unattainable performance metrics (fracture strain >50% and PCE >10%) are achieved simultaneously for the resulting photovoltaic films. Furthermore, an overall evaluation parameter y is proposed for the efficiency-cost- stretchability balance of photovoltaic blend films. The y value of dilute-absorber system is two orders of magnitude greater than those of prior state-of-the-art systems. Additionally, intrinsically stretchable devices are prepared to showcase the mechanical stability. Overall, this work offers a new avenue for constructing and comprehensively evaluating intrinsically stretchable organic electronic films.
有机太阳能电池（OSCs）在可穿戴电子产品中具有应用潜力。除了高功率转换效率（PCE）外，高性能可穿戴OSCs还需要优异的拉伸性能和机械稳定性，而目前的指标几乎无法满足可拉伸的要求。在此，这项工作提出了一种简便且低成本的策略，通过引入一种易于获得的聚合物弹性体作为全聚合物光伏共混物的稀释剂来构建本征可拉伸的OSCs。值得注意的是，首次在OSCs活性层中实现了高达1000%的断裂应变的创纪录高拉伸性以及在循环拉伸试验下弹性回复率>90%的机械稳定性。具体而言，性能最佳的全聚合物光伏共混物在混合后拉伸性能提高了250倍。所得光伏薄膜同时实现了以前无法达到的性能指标（断裂应变>50%和PCE>10%）。此外，还提出了一个综合评估参数y，用于评估光伏共混薄膜的效率-成本-拉伸性平衡。稀吸收剂体系的y值比先前的先进体系高出两个数量级。此外，制备了本征可拉伸器件以展示其机械稳定性。总体而言，这项工作为构建和全面评估本征可拉伸有机电子薄膜提供了一条新途径。
