Molecular Engineering of Multivariate Porous Aromatic Frameworks for Recovery of Dispersed Uranium Resources

Abstract

Uranium plays an indispensable role in the sustainable development of nuclear industry, and the recovery of uranium from nuclear wastewater is one way to solve the shortage of uranium resources. However, the recovery of uranium resources from nuclear wastewater remains a challenge due to the interfere of coexisting ions. Herein, ratios of the adsorption group and photocatalytic enrichment group are well‐designed and controllably assembled into the porous aromatic frameworks (PAFs) using molecular engineering strategy to realize high uranium recovery efficiency and high resistance to interfering ions. The optimally coordinated multivariate PAF material PAF‐AN2T8‐AO exhibits bifunctions of adsorption and photocatalytic enrichment and thus, achieves high enrichment selectivity and high uranium recovery efficiency of 99% under simulated sunlight irradiation. Compared to PAFs with only adsorption group or photocatalytic group, the uranium recovery capacity of the optimized PAF is enhanced by 1.2 times and 2.3 times, respectively. Mechanistic studies reveal that the product of photocatalytic uranium on PAF‐AN2T8‐AO is air‐stabilized solid crystal metastudtite ((UO2)O2∙2H2O). This work provides a guiding method for designing adsorption‐photocatalytic bifunctional materials and proposes a more environmentally adaptable strategy for dispersed uranium resource recovery.