Selective photocatalytic oxidation of NO to nitrate (NO3–), rather than toxic NO2, remains highly challenging due to uncontrollable reaction intermediates and extremely low charge migration efficiency. Herein, we design a photocatalyst (BiSbO4/AgCl-Ag-70) that integrates a BiSbO4/AgCl heterojunction with spatially correlated Ag nanoparticles (NPs) and oxygen vacancies (OVs) to synergistically regulated charge dynamics and reaction pathways. The formation of a heterojunction establishes a built-in electric field, which facilitates directional electron transfer. Meanwhile, Ag NPs and abundant OVs induce localized electron redistribution, promoting the generation of reactive oxygen species (ROS), and enhancing the selectivity toward nitrate. The BiSbO4/AgCl-Ag-70 photocatalyst immobilized on ceramic foam achieved 90.0 % NO removal efficiency with excellent stability, maintaining 79.0 % removal after 720 min, while generating only 22 ppb (4.2 %) of toxic NO2. Furthermore, the BiSbO4/AgCl-Ag-70 catalyst demonstrated a high nitrate selectivity of 89.2 %. Mechanistic studies combining in situ DRIFTS and DFT calculations reveal that the introduction of OVs activates O2/H2O molecules, thereby promoting a reactive oxygen species-dominated pathway for the conversion of NO to NO3–, rather than the route involving the formation of the toxic intermediate NO2. This work provides a strategy for the selective removal of NO by designing a material with rapid interface charge transfer and abundant surface active sites, thereby achieving precise regulation of the photocatalytic oxidation pathways.
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