Flexocatalytic Effect Enables Uranyl Separation by the Organic–Inorganic Hybrid Material

The development of novel technologies for efficient uranyl separation from wastewater is highly desirable, addressing uranium recovery challenges and environmental remediation. Herein, the hybrid material Co[C₄H₄N₂]V₄O₁₀ is reported as a novel flexoelectric catalyst for highly efficient uranyl separation from wastewater. The material demonstrates robust flexocatalytic activity under demanding conditions, including high-salinity environments, a broad pH range (1.52-11.02), and low ultrasonic power input (20 W). Notably, Co[C₄H₄N₂]V₄O₁₀ achieved outstanding uranium extraction performance in various water matrices, including mining wastewater, seawater, and river water, highlighting its potential for practical applications. By combining DFT calculations, FEM simulations, and comprehensive experimental characterizations, the flexoelectric uranyl separation mechanism is elucidated, which proceeds through the efficient conversion of soluble U(VI) into insoluble UO₂ and (UO₂)O₂·2H₂O. The anisotropic bonding environments in Co[C₄H₄N₂]V₄O₁₀ enhance deformability along the predominant crystal growth axis, which is identified as the primary origin of its flexocatalytic capability for uranyl separation. This work establishes a structure-activity relationship for flexoelectric-driven uranyl separation, offering a promising strategy for wastewater remediation.