Molecular Radiative Funneling Mitigates Multimodal Optical Losses in >19.7% Efficiency Flexible Organic Solar Cells

ABSTRACT Recycling plasmonic energy from non‐radiative damping is essential for overcoming efficiency limits in plasmon‐mediated optoelectronic systems, yet is often restricted by the lack of an integrated pathway that converts near‐field dissipation into usable optical output. Here, we establish a plasmon‐to‐photon relay that bridges the gap between parasitic plasmonic loss and usable photon flux. By tailoring multiple‐resonance thermally activated delayed fluorescence (MR‐TADF) mediators from a planar H‐BN to the sterically expanded TPS‐BN, we simultaneously strengthen near‐field capture via plasmon‐induced resonance energy transfer (PIRET) and preserve high radiative efficiency by suppressing intermolecular exciton loss. Upon integration into silver nanowire‐based flexible organic solar cells (FOSCs), this configuration effectively intercepts multimodal optical losses, including interfacial plasmonic dissipation and broadband photon escape, and redirects them into a radiative flux, which are preferential harvested by the active layer. Consequently, this radiative funneling enables a champion device with a record efficiency of 19.75%. This work highlights molecular spatial configuration as a determinant for regulating plasmon‐mediated energy flow and spectral distribution in high‐performance plasmon‐mediated optoelectronic devices.