Photothermal therapy (PTT) is emerging as a promising cancer treatment, but uneven heat distribution increases side effects and reduces treatment precision, where high-temperature zones risk inducing undesired inflammation, while low-temperature regions are insufficient due to upregulation of heat shock proteins (HSPs). Herein, a gas-assisted PTT strategy is designed to link near-infrared heptamethine cyanine (Cy7) with self-immolative phenyl thiocarbonate (PTC), a hydrogen sulfide (H