ABCABC Stacking‐Enabled Non‐Centrosymmetry 3R‐ZnIn ₂ S ₄ Nanosheets for Piezocatalytic Uranium Extraction

ABSTRACT Piezoelectric materials for uranium extraction have attracted increasing attention, as they offer a self‐powered, light‐independent strategy to harness ambient mechanical energy. However, natural mechanical energies are typically weak and low‐frequency, necessitating materials with high flexibility, facile deformation, and large surface area. Herein, we demonstrate that the ABCABC stacking sequence along the c ‐axis in two‐dimensional (2D) 3R‐ zinc indium sulfide (3R‐ZnIn 2 S 4 ) nanosheets induces intrinsic non‐centrosymmetry, enabling robust piezocatalysis for on‐site hydrogen peroxide (H 2 O 2 ) generation and simultaneous uranium extraction. Density functional theory (DFT) calculations confirm that solvation effects enhance the lattice flexibility and intrinsic dipole moment of 3R‐ ZnIn 2 S 4 , resulting in the formation of an electron‐rich surface that thermodynamically favors the two‐electron oxygen reduction reaction (2e− ORR) for H 2 O 2 generation. Under mild ultrasonic agitation (35 kHz, 50 W), the 3R‐ZnIn 2 S 4 nanosheets achieved a H 2 O 2 yield of 276.7 µmol g −1 h −1 and a uranium extraction capacity of 763.2 mg g −1 . Mechanistic investigations elucidate that the uranium extraction process proceeds through a dual‐coordination pathway, integrating direct piezoelectric reduction and in situ H 2 O 2 ‐mediated complexation of uranium species. Notably, 3R‐ZnIn 2 S 4 demonstrates excellent cycling stability over five cycles, high selectivity toward uranium, and effective anti‐biofouling performance under ultrasonic conditions (35 kHz, 50 W). Collectively, our findings establish stacking‐induced piezoelectricity as a light‐independent strategy for sustainable uranium extraction to support nuclear energy development.