Synergistic Electrochemistry of a 2D Van der Waals Heterostructure of Antimonene@Amidoximated Layered Double Hydroxide for Portable Uranyl Detection.

High-recognition materials are crucial for the development of uranyl sensors for the prevention of uranium contamination and its human health risks. Herein a novel 2D van der Waals (vdW) heterostructure of antimonene-loaded amidoximated nickel-aluminum layered double hydroxides (antimonene@AO-NiAl-LDHs) is prepared as the electrode probe for the electrochemical determination of trace uranyl. NiAl-LDHs are amidoximized and then self-assembled on antimonene via vdW bonding, as revealed by small-angle X-ray scattering measurement and first-principles calculations. Electrochemical measurements indicate that antimonene@AO-NiAl-LDHs exhibits accelerated reaction rate by exploiting the abundant active sites of AO-NiAl-LDHs and fast charge transfer of antimonene as a synergistic effect. The antimonene@AO-NiAl-LDHs-modified electrode is optimized to obtain a linear range of 4.2 × 10-9-4.2 × 10-7 M and a limit of detection of 7.7 × 10-10 M. A portable electrochemical uranyl sensing device is further constructed and demonstrate good applicability for real-world water analysis. The results extend the promising potential of 2D vdW heterostructures for field detection of trace uranium and other water contaminants.