Preparation of nanoparticles-assembled Cu2O microspheres by ultrasound-assisted polyol process and their adsorption performance

Cuprous oxide microspheres (Cu2O SPs) assembled by nanoparticles were successfully prepared via a facile ultrasound-assisted polyol process using cupric acetate monohydrate as a precursor and diethylene glycol as both solvent and reducing agent, and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption-desorption. Results showed that the as-prepared product was cubic Cu2O without any impurity and displayed microsphere morphologies with diameters of 250-300 nm, which were assembled by nanoparticles. The as-prepared Cu2O SPs exhibited excellent adsorption capability for methyl orange (MO). Kinetics and isotherms studies showed that the adsorption process of MO onto Cu2O SPs followed pseudo-second-order and Langmuir models. The maximum MO adsorption capability according to the Langmuir model under different concentrations ranging from 90 to 300 mg/L was estimated to be 885.0 mg/g. Moreover, Cu2O SPs can be regenerated by photocatalytic degradation of adsorbed MO.