Surface oxygen vacancies enriched FeOOH/Bi2MoO6 photocatalysis- fenton synergy degradation of organic pollutants

To achieve rapid separation of photogenerated charges, increase photocatalytic degradation activity, a visible light-driven FeOOH/Bi2MoO6-OVs photocatalyst was designed and successfully fabricated via solvothermal synthesis and calcination. H2O2 was added under visible light irradiation to form a heterogeneous photocatalysis-Fenton synergy system. Using visible light irradiation, 10% FeOOH/Bi2MoO6-OVs had the best degradation activity. The removal efficiency of phenol was 100% within 3 h, which was 1.54 times and 1.33 times of the degradation efficiency of photocatalysis and Fenton alone, respectively. The catalyst has high removal activity for various pollutants and good cycle stability. Hydroxyl radicals and superoxide radicals have proven to be the main active substances and a reasonable catalytic mechanism was proposed. Surface oxygen vacancy can not only reduce the width of band gap, promote the separation and migration of photogenerated electron-hole pairs, but also make the OO bond of H2O2 elongate and weaken, making it easier to react with FeOOH and realize the synergistic effect of photocatalysis-Fenton. Simultaneously, the oxygen vacancies located near the valence band can capture holes, and the holes are rapidly transferred to the surface of the catalyst and participated in the degradation of pollutants.