Photocatalytic degradation of phenolic compounds of defect engineered Fe3O4: An alternative approach to solar activation via ligand-to-metal charge transfer

Defect engineered Fe3O4 nanoparticles (NPs) with magnetic properties can act as efficient photocatalysts in spite of no intrinsically photocatalytic property of bare Fe3O4. The purpose of this study is to confirm the possibility whether the modified Fe3O4 NPs can be an efficient photocatalyst by engineering the surface defects without compromising the magnetic properties of Fe3O4 NPs. Herein, we report a facile method to introduce surface defects on Fe3O4 and Cr@Fe3O4 NPs without degrading their magnetic properties via simple pH treatments at moderate temperatures. Our results showed that Cr@Fe3O4 NPs fabricated under basic conditions, denoted as Cr@Fe3O4-B NPs, showed a clear electronic structural evidence for surface defects on Fe3O4. The presence of defects on Fe3O4 induced an alternative approach to solar activation via ligand-to-metal charge transfer to drive selective photocatalytic degradation of phenolic compound without losing its magnetic property. It is highly desirable to seek a strategy for achieving the recovery of catalysts using a magnet, while minimizing the loss of catalyst and the cost for a complicate recovery process.