Enhanced photocatalytic degradation of EMPs by hydrogenation modified different morphologies α-Fe2O3-x

The photocatalytic efficiency of hematite (α-Fe 2 O 3 ) is limited by its photoexcited state lifetime and diffusion length. By adjusting the surface structure, the photogenerated electron pairs can migrate to the surface and the charge recombination can be suppressed, which can effectively solve these problems and improve the photo-Fenton performance. In this study, four kinds different morphologies of α-Fe 2 O 3 - x (truncated hexagonal bipyramidal, cubic, hexagonal shape, and spherical) were synthesized by hydrothermal method , and a photocatalyst (H-α-Fe 2 O 3 - x ) with higher catalytic activity was prepared by hydrogenation. The results of UV–Vis DRS , PL , Raman, and XPS analysis , the oxygen vacancies and Fe (II) species were introduced into the α-Fe 2 O 3 catalyst after the hydrogenation reaction. The H-α-Fe 2 O 3 - x showed good degradation performance for TC and DX as EMPs model pollutants. The results show that the formation of oxygen vacancy and Fe 2+ is the main factor to improve the photocatalytic activity of the reaction system. Furthermore, the reaction mechanism revealed that reactive radicals involved in the H-α-Fe 2 O 3 - x photocatalytic system were •OH, •O 2 − , and h   +  responsible. This study provides an alternative technology for an easy and effective means for bandgap engineering to improve the photocatalytic performance of photocatalysts and facilitate widening environmental application.