Vacancy engineering modulates spin polarization to enhance the charge dynamics of CuIn5S8 for photocatalytic sterilization.

Photocatalytic sterilization technology is a strategy that is environmentally friendly for killing drug-resistant bacteria using solar energy. The role of reactive oxygen species (ROS) required for sterilization depends on the charge separation properties of the photocatalyst. Therefore, we modified the photocatalytic performance of CuIn5S8 by fabricating S-vacancies based on the work function (Φ) theory. The spin state density calculations show that S-vacancies lead to spin polarization, and it is easier to separate electrons and holes when their spin directions change. Electron paramagnetic resonance (EPR) results show that Vs-CuIn5S8-3 can produce more ROS. Under visible light irradiation, Vs-CuIn5S8-3 killed 99% of E. coli and MRSA in natural water within 30 minutes. The work adopted S-vacancies to regulate spin polarization and improve photocatalytic activity, which has great potential in natural water disinfection. [ABSTRACT FROM AUTHOR]