A Dual‐Function Hemicyanine Material with Highly Efficient Photothermal and Photodynamic Effect Used for Tumor Therapy

Small molecular organic optical agents with synergistic effects of photothermal therapy (PTT) and photodynamic therapy (PDT), hold credible promise for anti-tumor therapy by overcoming individual drawbacks and enhancing photon utilization efficiency. However, developing effective dual-function PTT-PDT photosensitizers (PSs) for efficient synergistic phototherapy remains challenging. Here, a benz[c,d]indolium-substituted hemicyanine named Rh-BI, which possesses a high photothermal conversion efficiency of 41.67% by exhaustively suppressing fluorescence emission, is presented. Meanwhile, the rotating phenyl group at meso-site induces charge recombination to enhance the molar extinction coefficient up to 13.58 × 10