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As the market of the Internet of Things (IoT) increases, great attention has been paid to the development of high-efficient organic photovoltaics (OPVs) utilizing artificial light. However, in a real indoor condition, the power density contribution of the artificial light cannot exceed 35% in the combination of indoor and outdoor irradiation, which indicates that the illumination of sunlight cannot be ignored during daytime. Hence, it is urgent to develop high-efficient OPVs in indoor conditions taking into account both sunlight and artificial light. In this work, a novel asymmetric molecule TB-4F was synthesized to trade-off the absorption spectrum that can be applied under both artificial light and sunlight. In conventional bulk-heterojunction (C-BHJ), it was figured out that due to nonoptimal morphology some carriers failed to be efficiently collected. Herein, a sequential deposition bulk-heterojunction (SD-BHJ) as an alternative fabrication method successfully enhanced the performance of OPVs, under both artificial light and sunlight, which was attributed to the favorable microstructure being vertically distributed in the active layer. Notably, the PCE was significantly increased by 25% for SD-BHJ compared to C-BHJ under artificial light, owing to the strong effect of trap-assisted recombination and dark current on PCE in the condition of low carrier density. Our result indicates that an asymmetric molecule with a blue-shifted spectrum fabricated by SD-BHJ can be a promising candidate that can be applied in indoor environments to harvest sunlight and artificial light simultaneously.

The ternary strategy is an effective method to improve the efficiency of organic solar cells (OSCs). Herein, high‐performance OSCs with over 18% efficiency using PM6 as donor and alloy‐like acceptor containing two highly structurally similar acceptors (Y6 and Y6‐1O) is obtained. The spectral overlap of Y6 and Y6‐1O can increase the collection of photons via enhancing the absorption in near infrared region, which is conducive to improve the short‐circuit current density (J SC). Meanwhile, beneficial electron transport channels are established by the construction of cascaded energy levels of Y6 and Y6‐1O in the ternary films. In addition, compared with Y6‐ and Y6‐1O‐based binary devices, enhanced charge mobility and suppressed charge recombination are observed in the optimal ternary OSCs, contributing to better performance. The improved performance of ternary devices based on the introduction of Y6‐1O is also attributed to the enhancement of photon capture and improved charge extraction as well as optimized blend morphology. A very promising ternary strategy is presented with two highly compatible acceptors to synergize the device performance in the development of high‐efficient OSCs.

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