Achieving the High Color Conversion Efficiency by Using Efficient Energy Transfer Rates in Organic Nanocrystals

Color conversion materials for next‐generation displays are fundamentally limited by architectures that rely on direct blue‐light absorption, requiring high‐emitter loading, thick films which often suffer from residual blue leakage, and instability. Here, we report a Förster resonance energy transfer (FRET)–dominated color conversion strategy based on surfactant‐stabilized organic nanocrystals (ONCs), in which nanoscale energy funneling, via resonant energy transfer, governs photon conversion efficiency rather than optical density. Binary color conversion films (CCFs) are constructed from blue‐emissive donor and green/red acceptor ONCs with precisely planned spectral overlap and nanoscopic proximity. This enables efficient FRET (70–80% efficiency and rate ≈8 × 10 8 s −1 ) that rapidly transfers energy from donors to acceptors prior to donor emission. The resulting mechanism effectively decouples blue absorption from emission, suppressing blue leakage and minimizing reabsorption losses. As a result, the ONC films achieve color conversion efficiencies of 85–90% and exhibit competitive performance relative to state‐of‐the‐art systems, with a lower concentration and thickness of 11–12 µm. These ONC films further preserve high color purity, enabling wide color gamuts of 88.76% BT.2020 and 112.2% NTSC, alongside excellent photostability under blue excitation. This work establishes FRET as a powerful design paradigm for ultra‐efficient, thin, and stable CCFs for display applications.