Fig. 2. Temperature-dependent antibacterial performance of Bi₂Te₃ NPs.

(A) Schematic illustration of the thermocatalytic mechanism for H₂O₂ generation under a temperature gradient created because of the applied temperature difference. (B) Generation of H₂O₂ by Bi₂Te₃ NPs under different temperature gradients at different time intervals. (C) Generation of H₂O₂ by different amounts of Bi₂Te₃ NPs at different time intervals at ΔT = 15°C. (D) Schematic representation of the antibacterial mechanism of Bi₂Te₃ NPs. (E and F) Antibacterial efficiency of Bi₂Te₃ NPs for Escherichia coli [E. coli; Gram-negative bacterium (E)] and Staphylococcus aureus [S. aureus; Gram-positive bacterium (F)] at various temperature gradients. (G) Plating results showing the concentration of E. coli after treatment at different temperature gradients. (H) Images of live (green fluorescence) and dead (red fluorescence) bacterial cells following different temperature gradients after 10 and 30 min of treatment. Scale bars, 100 μm. Results are plotted as means ± SD (n = 3).