Specifically, the efficient photovoltaic materials have bithiophene, thieno[3,2-b]thiophene or terthiophene sequences along conjugated backbones. In this contribution, a fluorinated terthiophene derivative ([2F]3T) is developed and used as additive to finely regulate the morphology of bulk heterojunction photoactive layers. Results show that the [2F]3T possess melting point of 75 °C and crystallization temperatures of 35 °C, and thus can serve as nucleation center at room temperature and plasticizer under thermal annealing to form favorable morphology with increased crystallinity and P-i-N like heterojunction. Therefore, the optimized PM6:Y6 based solar cells with [2F]3T additive reach efficiency of 17.6%, which is higher than that of the control devices with a modest efficiency of 16.3%. Moreover, the fill factor (FF) and short circuit current (J_sc) increase significantly from 72.8% and 26.3 mA cm⁻² for the control devices to 76.6% and 27.0 mA cm⁻² for the devices with [2F]3T additive. Carrier dynamic studies reveal that the favorable morphology in [2F]3T-based devices translate into enhanced charge generation, transportation, and suppressed charge recombination. These findings make clear that the additive featuring with similar chemical building blocks as that of the organic photovoltaic materials has broader implications for further optimization of organic solar cells.

具体来说，高效光伏材料有二噻吩、噻吩[3,2- b]噻吩或三噻吩序列沿共轭骨架。在这项贡献中，开发了一种氟化三噻吩衍生物 ([2F]3T)，并将其用作添加剂，以精细调节体异质结光敏层的形态。结果表明，[2F]3T的熔点为75 ℃，结晶温度为35 ℃，因此在室温下可作为成核中心，在热退火时可作为增塑剂，形成结晶度增加的良好形貌和类PiN异质结。因此，具有[2F]3T添加剂的优化PM6:Y6基太阳能电池的效率为17.6%，高于16.3%的适度效率的控制装置。此外，填充因子 (FF) 和短路电流 ( J _sc^{) 从控制设备的 72.8% 和 26.3 mA cm -2}显着增加到具有 [2F]3T 添加剂的设备的 76.6% 和 27.0 mA cm ^-2。载流子动力学研究表明，基于 [2F]3T 的器件中的有利形态转化为增强的电荷产生、传输和抑制的电荷复合。这些发现清楚地表明，具有与有机光伏材料相似的化学结构单元的添加剂对进一步优化有机太阳能电池具有更广泛的意义。