Heterogeneous Cu2O–Au nanocatalyst anchored on wood and its insight for synergistic photodegradation of organic pollutants

Abstract

In this study, a Cu2O–Au nanoparticles (NPs) heterojunction catalyst anchored on wood was developed by in situ reduction and hydrothermal treatment, and the properties of the catalyst were systematically characterized. The catalyst exhibited prominent photocatalysis of methyl orange (MO, 0.169 min− 1), and tetracycline (TC, 0.122 min−1) which were degraded completely within 20 min. Even after four recyclings, the efficiency of MO degradation by the catalyst remained at 80%. The natural wood with three-dimensional porous structures acted as a reducing agent and a stabilizer for Au NPs and Cu2O, which helped to maintain high performance and reusability. The presence of Au NPs mediated the light-induced electron transfer and enhanced the absorption of visible light for promoting photocatalytic activity. The intermediates of contaminants within the degradation process were characterized by liquid chromatography-mass spectrometry. Additionally, the photogenerated superoxide radicals and holes were identified by electron spin resonance. Thus, the potential degradation mechanism catalyzed by the Cu2O–Au NPs-wood was proposed. This findings of this study valorizes biomass as a photocatalyst for wastewater remediation.