Efficient removal of radioactive iodide by three-dimensional Cu@Cu O: An adsorption and electrocatalytic oxidation coupling process

Electrochemical promotion technology, an environmentally friendly and facile strategy, is becoming increasingly attractive to researchers. In this work, a novel [email protected]2O foam block composite material was constructed through a one-step hydrothermal method. The product was then employed as the anode and electrified to catalyse removal of radioactive iodide ions (I−) in the liquid phase. The removal rate of I− sharply increased to 96.65 % under electrification, which is a 4.5-fold increase over that without electrification. The current strength had an impact on this result, and the removal was still relatively high in a wide range of pH values. The composite material had good reusability and could maintain good performance after simple separation. Therefore, based on X-ray diffraction and X-ray photoelectron spectroscopy analysis, we proposed a mechanism of electrochemical oxidation and adsorption coupling for the iodine removal. As [email protected]2O adsorbed I− to form CuI, the current flow oxidised I− to I2, which finally was adsorbed by the formed CuI. Therefore, the current provides services of accelerating I− movement and oxidation. This coupling model of electrocatalytic oxidation and adsorption provides us with a new research method to remove iodide from water.