A graphene-hidden structure with diminished light shielding effect: more efficient graphene-involved composite photocatalysts

Abstract

Graphene sheets possess not only outstanding advantages in the field of photoelectrochemistry, but also some disadvantages that affect their performance. However, less attention has been paid to these negative effects while improving the properties of graphene-based materials. The light shielding effect of graphene sheets is a significant obstacle for their use in photocatalytic areas mainly due to their unavoidable exposure to light, which seriously restricts further development of the photoactivity of graphene-involved composites. Herein, to suppress such a negative effect, a type of graphene-hidden structure has been constructed, in which the graphene sheets are placed under a TiO₂ spherical shell. Being well-hidden under the shell, the light shielding influence caused by these built-in graphene sheets is greatly reduced, which enables the exposed TiO₂ to use light more efficiently compared to those wrapped in graphene. As a result, these hidden graphene sheets can better enhance the performance of TiO₂ in the photocatalytic reduction of nitro-aromatics. Such a graphene-hidden structure weakens the light shielding disturbance while highlighting the advantages of graphene in photocatalysis processes, which may further broaden the use of graphene in the field of photoelectrochemistry.