<p>Photocatalytic extraction of U(VI) from uranium mine wastewater represents an economical, eco-friendly, and efficient strategy. However, the primary challenge is that the high concentration of&#xa0;H⁺ in the highly acidic wastewater severely inhibits the interfacial reaction between uranyl ions and the photocatalyst surface, resulting in the loss of photocatalytic activity. Oxygen vacancies (OVs) were successfully introduced into phosphorus oxynitride, providing additional active sites to mitigate the competitive adsorption of H⁺. Under acidic conditions, these oxygen vacancies exhibit a segregation effect, leading to the accumulation of H⁺ at the OVs. This process effectively liberates remote active sites for the efficient capture of UO₂²⁺. Simultaneously, the OVs enhance charge separation and carrier transport efficiency. This dual functionality enables the visible-light-driven photocatalytic reduction of U(VI), achieving a high extraction capacity of 624&#xa0;mg&#xa0;g^–¹ under strongly acidic conditions (pH = 2.0). This work provides a strategy for the efficient reduction of U(VI) under acidic environment.</p>