Oxygen vacancy-rich cuprous oxide microspheres exhibit strong absorption and high oxidative energy level for deep photodegradation of tetracycline

Abstract

In this study, a Cu2O microsphere (WY1) was hydrothermal synthesized by employing a CTAB-cocoylsarcosine sodium composite micellar. WY1 has an unifirm hollow spherical structure formed by agglomeration of nanoparticles, and the results of X-ray photoelectron spectroscopy and electron paramagnetic resonance indicate that WY1 contains significantly increased oxygen vacancies. The degradation efficiency of WY1 for 40 mg L−1 TC reached 93.26% after 60 min visible-light irradiation, which was 2.04 times higher than that of the product prepared without soft template (WNT). Especially, 81.67% residual rate of total organic carbon in the degradation of TC over WY1 was 17.83 times higher than that of WNT (4.58%). The spectral and electrochemical data reveal that the position of valence band of WY1 was exceeded the H2O/·OH potential, and the ·OH species rarely played a key role in the photocatalytic degradation of tetracycline by cuprous oxide. In addition, the ·O2− species were generated by forming the electron transfer pathway with aid of oxygen vacancy-mediated trap, acting as another major active species, which followed a deep photodegradation mechanism of hydroxyl and superoxide radicals dual activities. The spatial agglomeration of cuprous oxide nanoparticles provides a new process for enhancing interfacial energy levels and inhibiting photocorrosion, which cater the antibiotic remediation.