Supporting Information

Stable Black Phosphorus/Bi2O3 Heterostructures for Synergistic

Cancer Radiotherapy

Hao Huang a, #, Lizhen He b, #, Wenhua Zhou a, Guangbo Qu c, Jiahong Wang a, Na Yang a, Jie Gao c, Tianfeng Chen b, *, Paul K. Chu d and Xue-Feng Yu a, *

a Center for Biomedical Materials and Interfaces, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People’s Republic of Chinab Department of Chemistry, Jinan University, Guangzhou 510632, People’s Republic of Chinac State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People’s Republic of Chinad Department of Physics and Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China

Corresponding Authors*Email: xf.yu@siat.ac.cn*Email: tchentf@jnu.edu.cn

# These authors contributed equally.

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Fig. S1. TEM and HR-TEM (inset) images of BP nanosheets.

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Fig. S2. XRD spectra of BP and BP/Bi2O3 nanosheets.

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Fig. S3. Stability of BP and BP/Bi2O3 nanosheets in air with humidity of about 95%.

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Fig. S4. (a) Absorption spectra and (b) TEM image the BP/Bi2O3 nanosheets with X-ray radiation.

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Fig. S5. SeNPs and Bi2Se3 NSs (10 µg/mL) promote radiation-induced singlet oxygen overproduction in A375 cells.

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Fig. S6. BP/Bi2O3 nanosheets promotes radiation-induced superoxide anion (O2•−)

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Fig. S7. Z-scheme enhanced PDT using BP/Bi2O3 heterostructures under X-ray irradiation.

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Fig. S8. (a) The cell viability of A375 cells after incubated with different concentration of BP and BP/Bi2O3 nanosheets, SeNPs and Bi2Se3 NSs. (b, c, and d) A375 cell viability after incubated with different drugs and under the X-ray radiation at 2 Gy, 4 Gy and 8 Gy.

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Fig. S9. SeNPs and Bi2Se3 NSs (0.6 µg/mL) enhance the inhibitory effects of X-ray at varied radiation doses on the colony formation and survival fraction of A375 cells.

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Fig. S10. Changes in body wight of melanoma xenografts bearing nude mice after intravenous injection of of BP/Bi2O3 nanosheets and/or X-ray radiation for 21 days (n = 10).

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Fig. S11. The biodistribution of Bi element in the injected mice after 1 day and 28 days.

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