A Novel Photothermal Nanocrystals of Cu7S4 Hollow Structure for Efficient Ablation of Cancer Cells

Cu2-x S nanocrystals(NCs), characterized by low cost, low toxicity, high stability and high photothermal conversion efficiency, provide promising platforms as photothermal agents. Herein, a novel twostep synthesis has been developed for Cu7S4 nanocrystals with hollow structure using the as-prepared copper nanoparticles as starting a solid precursor followed by hot-injection of sulfide source.The Cu7S4 NCs exhibit intense absorption band at Near-infrared(NIR) wavelengths due to localized surface plasmon resonance(LSPR)mode, which can effectively convert 980 nm-laser energy into heat.Moreover, the localized high temperature created by Cu7S4 NCs under NIR irradiation could result in efficient photothermal ablation(PTA) of cancer cells in vivo, demonstrating a novel and promising photothermal nanomaterials.