Construction of heterostructured CaCO3/NiS with enhanced photocatalytic antibacterial performance under visible light

CaCO3/NiS heterostructured composites were synthesized via the facile hydrothermal method. CaCO3/NiS showed the best photocatalytic bactericidal performance when the addition was 15 mg. Under 10 min visible light irradiation, about 90 % of Staphylococcus aureus was killed by composite, which was 4.5 times and 3 times faster than CaCO3 and NiS. The addition of CaCO3 significantly improves the photocurrent response and electron-hole pair separation rate of NiS and effectively increases the yield of active free radical groups. These groups cause the bacterial cell membrane to be destroyed and the internal proteins to be flow out, achieving the effect of killing bacteria. The solitary electron pair in the CaCO3/NiS composite absorbs visible light energy, making lots of atoms leave the equilibrium check point and effectively preventing the recombination of photogenerated electrons and holes. The inherent active substances (center dot OH and center dot O2-) cooperate with vacancies to enhance bacte-ricidal performance. The design and synthesis of CaCO3/NiS composites effectively improve the sterilization effect and its application can be expected.