Fabrication of Z-scheme flower-like AgI/Bi2O3 heterojunctions with enhanced visible light photocatalytic desulfurization under mild conditions

Abstract

In current study, hierarchical flower-like AgI/Bi2O3 heterostructured nanocomposites were fabricated successfully by a glycothermal approach. In the production process, the various conditions such as reaction time and temperature and type of surfactant were investigated, which by optimizing these parameters, uniform flower-like AgI/Bi2O3 heterojunction nanostructures were formed. The as-obtained AgI/Bi2O3 binary nanocomposites exhibited enhanced visible-light-driven photocatalytic performance towards the desulfurization of dibenzothiophene under mild conditions. Results indicated that the porous flower-like AgI/Bi2O3 photocatalyst with suitable energy band gap (2.81 eV), has superior photocatalytic desulfurization efficiency about 93% after 2 h visible light irradiation, even after 5 recycles. The enhanced photocatalytic performance could be attributed to the special architecture and formation of Z-scheme system in the AgI/Bi2O3, which results in the efficient separation and transfer of photo-generated charge carriers. Furthermore, the photodesulfurization mechanism was deduced by active species trapping experiments and the results represented that h+ and ·O2− species played main roles in the photo-oxidation reactions.