Frustrated Lewis pairs created by Ce-doped Bi2MoO6: A universal strategy to promote efficient utilization of H2O2 for Fenton-like photodegradation

Abstract

Photo-Fenton-like technology based on H₂O₂ is considered as an ideal strategy to generate reactive oxygen species (ROS) for antibiotic degradation, but O₂ overflow in the process severely limits the utilization efficiency of H₂O₂. Herein, we fabricate Bi₂MoO₆ (BMO) photocatalyst modified with Frustrated Lewis pairs (FLPs) as a Fenton catalyst model for enhancing reuse of spilled O₂. The FLPs created by the introduction of cerium and oxygen vacancy were found to contribute to regulate the electronic structure of BMO and further improve the acidic and basic properties of photocatalyst surface. More importantly, the frustrated acid and base sites can enhance the H₂O₂ and O₂ interfacial adsorption process and provide an Ce⁴⁺-O_v-O^2- active site on the surface of Ce-BMO nanosheets, which can promote O₂/•O₂^-/¹O₂/H₂O₂ redox cycles to achieve high H₂O₂ utilization efficiency. Specifically, in the experiment using tetracycline as a photocatalytic degradation object, the degradation activity of Ce-BMO was 2.15 times higher than that of BMO pure phase. Quenching experiments and EPR assays also confirmed that ¹O₂ and •O₂^- were the dominant oxidative species. This study systematically reveals the design of Fenton photocatalytic active sites at the atomic scale and provides new insights into constructing FLPs photocatalysts with high H₂O₂ utilization efficiency.

Keywords: Bi(2)MoO(6); Frustrated Lewis acid-base pairs; H(2)O(2) utilization efficiency; Oxygen activation.