Synthesis of Highly-Active Cu₂O for Degradation of MO Dyes under Light and Non-light Conditions by Electrochemical Method

Abstract—The growth of Cu₂O crystal planes was be controlled by adding surfactant to the NaCl solution in this manuscript. The structure and composition of the synthesized Cu₂O particles were characterized by X‑ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), and specific surface area test method (BET). The photocatalytic activities were evaluated by degrading methyl orange (MO) solution under magnetic stirring. The results shown that the synthesized Cu₂O particle was spherical self-assembly structure when the surfactant was CTAB, and behaved higher degradation performance. Under dark conditions, the adsorption efficiency of 100 mg L^–1 MO solution reached 67.08% in the first 1 min by 0.33 g L^–1 CTAB-Cu₂O, and after 15 min, the adsorption degradation efficiency of MO had reached 99.17%. The maximum adsorption capacity of CTAB-Cu₂O was 297.28 mg g^–1. The adsorption kinetics obeyed pseudo-second-order kinetics and followed the Freundlich isotherm.