Bioinspired hierarchical 3D flower-in-ridge hybrid structure for the photodegradation of persistent organic pollutants

The development of next-generation photocatalysts has consistently gained inspiration from the evolution of natural nanostructures regarding their fabrication and application for the elimination of persistent organic pollutants (POPs). Herein, we synthesized blue-colored oxygen-vacant Bi2WO6-x inside butterfly wing architectures (BW-Bi2WO6-x) via modified functionalization and solvothermal techniques. Given that the (WO4)2- layer in Bi2WO6 structurally resembles the structure of WO3, the introduction of oxygen vacancies (OVs) boosts the solar light absorption in comparison to the short visible light absorption range (<450 nm) in pristine Bi2WO6 (P-Bi2WO6). Hence, the fabricated BW-Bi2WO6-x sample exhibited broadened photo-absorption over the visible to NIR wavelength range, improved semiconductor attachment on the wing architecture and heightened surface area with numerous active sites for the adsorption of POP molecules. The performance of the BW-Bi2WO6-x photocatalyst was monitored for the elimination of methylene blue (MB), rhodamine B (RhB) and 4-chlorophenol (4-CP) under UV light exposure, yielding 91%, 92% and 94% degradation, respectively, in 60 min. Similarly, the degradation efficiencies of 94%, 98% and 98% for the photodegradation of MB, RhB and 4-CP under visible light for 60 min, respectively, were observed. Under NIR light, 80%, 79% and 85% degradation efficiencies were observed for MB, RhB and 4-CP, respectively, after 60 min. Therefore, the proposed BW-Bi2WO6-x sample can provide insights and inspire the development of photo-responsive materials for applications in energy, defense and water treatment.