Interface-Constrained Layered Double Hydroxides for Stable Uranium Capture in Highly Acidic Industrial Wastewater

Low acid endurance of layered double hydroxides (LDHs) limits their uranium(VI) [U(VI)] adsorption capability from harsh industrial wastewater. Here, we demonstrate magnesium–cobalt LDHs (Mg–Co LDHs) anchored in situ onto the pore channel of dendritic fibrous nanosilica (DFNS) via an interface-constrained strategy. The synergy of Mg–Co LDHs and DFNS not only improves the endurance of the Mg–Co LDH under harsh acidic conditions but also increases the number of active sites of DFNS. Thus, DFNS@Mg–Co LDH shows a high U(VI) uptake capacity (1143 mg g–1) at pH = 3 and C0 = 598.7 mg L–1, which is about 4.8-fold higher than that of pristine DFNS. The DFNS@Mg–Co LDH exhibits excellent U(VI) uptake in various background water circumstances due to its acid endurance and highly selective adsorption. This interface-constrained strategy provides LDH materials with durability under extremely acidic conditions along with a high adsorption capacity, which is promising for uranium capture from various water fields.