A floating photocatalytic fabric integrated with a AgI/UiO-66-NH2 heterojunction as a facile strategy for wastewater treatment

Abstract

With an increased need of wastewater treatment, application of photocatalysts has drawn growing research attention as an advanced water remediation strategy. Herein, a floating photocatalytic fabric in a woven construction was developed for removal of Rhodamine B (RhB) in water. For an efficient photocatalytic reaction, AgI nanoparticles were grown on the surface of UiO-66-NH₂ crystals in a layered structure, forming a heterojunction system on a cotton yarn, and this was woven with polypropylene yarn. The floating photocatalyst demonstrated the maximized light utilization and adequate contact with contaminated water. Through the heterojunction system, the electrons and holes were effectively separated to generate reactive chemical species, and this eventually led to an enhanced photocatalytic performance of AgI/UiO@fabric reaching 98% removal efficiency after 2 hours of irradiation. Photodegradation of RhB occurred mainly by superoxide radicals and holes, which were responsible for de-ethylation and decomposition of an aromatic ring, respectively. The kinetics of the photocatalytic reaction suggested that circulation of solution by stirring affected the photocatalytic removal rate. The recycle test demonstrated the potential long-term applicability of the developed material with structural integrity and catalytic stability. This study highlights the proof-of-concept of a floating photocatalytic material for facile and effective water remediation with repeated usability.