The phenomenon of rapid migration of photogenerated charges in natural photosynthetic systems has motivated the design of efficient photocatalysts capable of fast charge separation and efficient reaction kinetics for photocatalytically assisted enrichment and separation of uranium U(VI) in uranium wastewater. In this study, we developed a biomimetic photocatalytic system MnOx/NH2-UiO-66-rGO (M/UiO-rGO) with spatially separated dual cocatalysts. Among them, rGO functions to capture electrons and participates in reduction reactions, while MnOx captures holes and participates in oxidation reactions. The M/UiO-rGO catalyst exhibits excellent performance in photocatalytic reduction of uranium (reaching 91.8% in 1 h), and even under natural light conditions, it exhibits excellent uranium removal ability (80.4%). Using multispectral coupling technology, we further confirmed that enriched uranium undergoes a continuous and complex reaction process of "capture-reduction-free radical oxidation-nucleation-crystallization". This work presents a viable strategy for designing biomimetic photocatalysts with efficient charge separation and rapid reaction kinetics for environmental purification purposes.
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