A general enlarging shear impulse approach to green printing large-area and efficient organic photovoltaics†
Green solvent-treated organic solar cells (OSCs) have demonstrated remarkable advantages in recent years for printing large-area photovoltaic devices. However, the high boiling point and poor solubility of green solvents lead to difficulties in morphological exploration and regulation, which are ultimately prejudiced against the upgrading of large-area OSCs. In this work, the shear impulse strategy is used to prepare high-performance scalable OSCs with green solvents. In PM6:Y6 films treated with o-XY, the shear impulse during film formation is improved by increasing the meniscus-guided coating (MGC) speed, which leads to achieving suitable phase separation. Therefore, the PCE of the device prepared by MGC is up to 15.1%, and the PCE of large-area devices (1 cm2) reaches 13.66%. Moreover, the critical conditions for the fabrication of homogeneous films are explored. To validate the universality of the shear impulse strategy, PM6:BTP-eC9 films are fabricated by the MGC method. A PCE of 17.15% is obtained for small-area (0.04 cm2) devices. Noticeably, the PCEs of large-area (1 cm2) rigid devices reached 15.50%, and a large-area module (25 cm2) exhibited an excellent PCE of 11.29%. Overall, the shear impulse strategy can effectively guide the lab-to-manufacturing translation of printing organic photovoltaic devices.