One body, two hands: photocatalytic function- and Fenton effect-integrated light-driven micromotors for pollutant degradation

Abstract

The threat of water pollution represents a serious global concern and requires rapid and efficient neutralization methods. Herein, we report novel two-in-one light-driven micromotors, i.e., light-driven TiO₂-Fe Janus micromotors with both photocatalysis and photo-Fenton processes, for efficiently degrading organic pollutants in contaminated water. The TiO₂-Fe micromotors moved rapidly by utilizing the photocatalytic H₂O₂ decomposition over TiO₂ under UV irradiation, as well as generating highly reactive oxygen species responsible for the in situ degradation of the organic pollutants into non-harmful products. Notably, such coupling of photocatalysis generated on the TiO₂ sides and the photo-Fenton process generated on the Fe sides, along with the rapid movement of these catalytic Janus micromotors, results in a synergetic effect that can greatly enhance the degradation of organic pollutants. The degradation efficiency of the TiO₂-Fe micromotors is 52-fold that of only Fenton effects, and it is further improved by 40% compared to photocatalytic degradation alone. Considering the excellent advantages of the high efficiency, simple structure, reusability and the bubble-driven property, the new “on-the-fly” TiO₂-Fe micromotor-based method has a promising potential for future water cleaning and waste-water treatments.