Enhanced desulfurization performance of model fuel by Cu–ZnO/TiO2 heterostructure†

A facile hydrothermal approach was employed to synthesize a novel Cu–ZnO/TiO₂ Z-heterojunction with a high density of defects, which was then utilized for the oxidative desulfurization process, demonstrating excellent photodegradation performance. The results showed that by adjusting components such as Cu, ZnO, and TiO₂, the removal efficiency of DBT reached 88.12% within a duration of 240 min. In the 5 repeated experiments, 7.5%Cu–ZnO/TiO₂ still exhibited high stability and could be reused. The improved photocatalytic performance of the 7.5%Cu–ZnO/TiO₂ composite can be attributed to its high light absorption capability and well-matched energy levels, which are due to the abundant presence of imperfections. The adoption of a Z-heterojunction has enabled efficient separation and transfer of photo-generated electrons and holes (e⁻/h⁺), thereby reducing the probability of charge carrier recombination.