High-efficiency separation and transfer of photo-induced charge carrier in graphene/TiO2 via heterostructure in magnetic field

Providing a driving force is an effective approach to boost the separation of photo-induced charge carriers. Photoelectrode application is the most accepted route. However, it is difficult to realize the high-efficiency photocatalytic activity of granular photocatalysts in suspension by applying the electric field. In this work, on the basis of the Lorentz force-driven improved separation of photo-induced charge carriers in TiO2 nanobelts, further enhancement of the charge transfer was achieved through constructing a heterostructure of reduced graphene oxide (rGO)/TiO2 nanobelts (NBs) in a magnetic field. The photocatalytic efficiency of the rGO/TiO2 NB heterostructure improved by 34% compared with pure TiO2 NBs under the same magnetic field conditions. This new strategy combined the Lorentz force generated in a magnetic field and the built-in electric field of rGO-TiO2 NBs to improve photo-induced charge carrier separation and transfer. Furthermore, a wireless microelectric potential was generated in rGO based on the electromagnetic induction effect, which additionally improved the charge transfer in rGO. This work provides a new idea to improve the photocatalytic activity of granular photocatalysts.