Facile fabrication of highly flexible and floatable Cu2O/rGO on Vietnamese traditional paper toward high-performance solar-light-driven photocatalytic degradation of ciprofloxacin antibiotic

Abstract

In this work, we successfully demonstrated the facile fabrication of highly flexible and floatable Cu₂O/rGO on Vietnamese traditional paper (VTP) for the solar-light-driven photocatalytic degradation of the antibiotic ciprofloxacin. The catalyst membrane was prepared by the green reduction of both Cu(OH)₂ to Cu₂O nanoparticles and graphene oxide to reduced graphene oxide. VTP has a fibrous structure with tiny fibers connected like a spider web and multiple layers in the form of a multidimensional array, which functions as a flexible and highly porous supporter to the catalyst. Moreover, the microfibrillated cellulose of VTP acts as micro-capillaries to drag ciprofloxacin (CIP) close to the active sites on the Cu₂O/rGO/VTP surface, which improves the adsorption capacity and photocatalytic efficiency of ciprofloxacin. The adsorption process is best described by the pseudo-first-order and Freundlich models. The maximum photodegradation of CIP by the catalyst is more than 80% attained after 1.5 h under solar light irradiation with a fixed CIP concentration of 10 mg L⁻¹. The catalyst membrane exhibited good reusability of up to 5 cycles.