Potential-aided recovery of iodide using 2-D nanosheet CuxO coating polymer/graphene/carbon fibers composite

Abstract 2-D nanosheet Cu2O doped CuO coating poly m-phenylenediamine and melamine/graphene/carbon fibers composite (CuxO/MPM/GFs) was firstly fabricated by compound electrochemical method. CuxO/MPM/GFs was successfully used to the recovery of iodide (I−1) from salt water by lower potential-aided sorption and desorption processes. The potential-aided recovery of I− at CuxO/MPM/GFs was characterized by FE-SEM, XRD, IR, Raman, XPS, UV–vis and electrochemical techniques in detail. The maximal adsorption capacity of 86.82 mg g−1 could be obtained with a pseudo-second-order model at 0.8 V for 210 min in pH 5.0, 0.1 M NaCl, and the process accompanied the generation of CuI, CuO and I5−. The I− could be quickly desorbed from the electrode with a transfer of CuI to Cu2O by cycle voltammetry from − 1.0 to 0.5 V for 90 cycles in pH 9.0, 0.1 M KNO3. Thus, CuxO/MPM/GFs was renewable in the continuous electrochemical-adsorption –desorption processes.