1. Characterization of B nanosheets, B-CuS and B-CuS-DOX TEM images of (A) B-CuS and (B) B-CuS; (C) Diameter of B-CuS-DOX; (D) XPS survey spectra of B nanosheets; (E) The selective XPS survey spectra corresponding to B1s spectra; (F) Hydrodynamic size change of B-CuS-DOX dispersed in saline, medium containing fetal bovine serum (FBS), human simulated body fluid (SBF) for 15 d; (G) UV-Vis-NIR spectra and (H) Zeta potential of B nanosheets, B-CuS and B-CuS-DOX; (I) Histogram of the relationship between DOX drug loading and DOX concentration. DOX: doxorubicin

2. Photothermal performance of B-CuS

3. Drug release curves of B-CuS-DOX in PBS solution with different pH and with or without NIR laser irradiation

4. In vitro cellular uptake of B-CuS-DOX

5. Evaluation of B-CuS-DOX on cell chemotherapy-PTT synergistic therapy (DOX: doxorubicin)

6. Observation of 4T1 cells stained with calcein AM and PI under confocal microscope (scale: 50 μm). DOX: doxorubicin

7. Detection of apoptosis of 4T1 cells after different treatments by flow cytometry (DOX: doxorubicin)