In-situ exfoliation and assembly of 2D/2D g-C3N4/TiO2(B) hierarchical microflower: Enhanced photo-oxidation of benzyl alcohol under visible light.

This study demonstrates the successfully fabrication of 2D/2D g-C 3 N 4 /TiO 2 (B) hierarchical microflowers via a hydrothermal in-situ exfoliation and assembled method. The structural and optical properties of g-C 3 N 4 /TiO 2 (B) are characterized by X-ray diffraction, transmission electron microscopy, as well as spectroscopic techniques. The recombination of g-C 3 N 4 with TiO 2 (B) significantly improves the photocatalytic performance in the photo-oxidation of benzyl alcohol to benzaldehyde using visible light (λ > 420 nm). Trapping experiments and electron spin resonance spectroscopy indicate the active radicals of ⋅O 2 −, ⋅OH and h+ are responsible for the enhanced activity. The heterojunction interface between g-C 3 N 4 sheets and TiO 2 (110) facets boosts separation efficiency of photogenerated charges, thus resulting into the high catalytic performance of g-C 3 N 4 /TiO 2 (B) composites. Density functional theory (DFT) calculations reveal that the charge transfer between the TiO 2 (B) and g-C 3 N 4 interface and the consequent formation of a built-in electric field at the interface, which are responsible for the high catalytic performance of g-C 3 N 4 /TiO 2 (B) composites. The study firstly reports a simple in-situ hydrothermal growth protocol to efficiently construct 2D/2D g-C 3 N 4 /TiO 2 (B) heterojunction composites and offer guidelines for design of a new synthetic strategy to prepare efficient photocatalysts. [Display omitted] • Novel 2D/2D TiO 2 (B)/g-C 3 N 4 hierarchical microflower was prepared by a hydrothermal in-situ exfoliation and assembled method. • The recombination of g-C 3 N 4 with TiO 2 (B) significantly improves the photocatalytic performance in the photo-oxidation. • The active radicals of ⋅O 2 − and h+ play an important role in the photo-oxidation. • DFT calculations reveal the built-in electric field at the TiO 2 (B)/g-C 3 N 4 interface is responsible for the superior activity. [ABSTRACT FROM AUTHOR]