Over 30% Efficiency in Halogen‐Free Solvent‐Processed Indoor Organic Photovoltaic Cells Enabled by Favorable Charge Carrier Dynamics

ABSTRACT Indoor organic photovoltaics (IOPVs) offer a promising candidate for sustainable and self‐sufficient power supply for Internet of Things (IoT) devices, where high efficiency critically depends on an in‐depth understanding of charge carrier dynamics. Using two structurally similar IOPV systems, we demonstrate that multichannel exciton‐to‐charge conversion and low trap‐state‐density charge transport enable efficient charge generation and collection under indoor illumination. Exciton dissociation in PTQ10:AFIC occurs predominantly through charge‐transfer (CT) states, with intrinsically faster state‐to‐state transitions relative to the PTQ10:ITCC system. This dynamic suppresses interfacial CT state accumulation, markedly reducing trap‐assisted recombination—a major loss contributor under indoor illumination. Additionally, a favorable vertical phase distribution in the PTQ10:AFIC system promotes charge separation and transport, further suppressing recombination and enhancing charge collection. Notably, the halogen‐free solvent‐processed PTQ10:AFIC device delivers a remarkable efficiency of 30.4% (3000 K, 2000 lux), and exhibits promising scalability, with 1 and 6.25 cm 2 devices delivering 29.1% and 27.4% PCE, respectively, under the same 2000 lux illumination. This work demonstrates that favorable charge carrier dynamics and morphology synergistically suppress trap‐assisted recombination in IOPVs, with such advantages disproportionately amplified under low‐carrier‐density indoor illumination conditions, highlighting the system's promising practical application potential.