Self-driven lattice strain and defective engineering of ultrathin BiOI facilitates the realization of significantly light-triggered degradation and sterilization capability

Abstract

The emerging pollutants and harmful bacteria remain a critical environmental concern, the efficient removal of pollutants and bacteria achieved by potential strategies is an important guarantee for the long-term development of human society. Herein, the ultrathin BiOI with endogenous stress and defects is designed to carry out the contaminant degradation and bacterial killing. Internal strain can effectively regulate the electronic structures to induce the formation of abundant reactive oxide species. Meanwhile, the abundant defect sites promote the separation and migration of carriers and activate photothermal conversion triggered by non-radiative relaxation to further accelerate the thermal motion of surrounding molecules, inducing the formation of a solid–liquid-gas three-phase interface to increase the photogenerated carrier reaction activity, and enhance the light absorption capacity by decreasing the bandgap, ultimately boosting photocatalytic capability. The experimental results show that when the strain and defect exist, the degradation efficiency of dye is increased by nearly 1.5 times, and the antibacterial efficiency is close to 99% even under low power light conditions. The rational design of strain-driven nanosystem enlighteningly provides a methodological support for the development of high-performance decontamination and disinfection catalysts in complex sewage system.