Ag-decorated novel h’-WO3 nanostructures for sustainable applications

Abstract

Recently, octahedral molecular sieve hexagonal structure (called h’) of WO3 was discovered for enhancing the physical and electrical properties, which is a promising candidate for electrochemical and energy storage applications. Nevertheless, the number of research on this new structure is still limited. In this study, novel h’-WO3 nanoflakes and nanopolygons decorated with Ag nanoparticles were synthesized using a one-step hydrothermal method. Ag decoration of the h’-WO3 nanostructure did not affect its crystal structure and morphology but remarkably enhanced its physicochemical properties. Ag decoration narrowed the optical bandgap, increased the oxygen deficiency, and increased the charge transfer between WO3 and the Ag NPs, which consequently increased the antibacterial and photocatalytic activity. The sample decorated with 5.0 wt% Ag showed the highest methylene blue degradation efficiency and antibacterial activity with S. aureus, while the sample decorated with 7.0 wt% Ag exhibited the highest antibacterial activity with E. coli. The sample decorated with 5.0 wt% Ag displayed the highest electrochromic performance with high optical contrast (ΔT ∼70% at 800 nm, 57.3% at 633 nm, and 35.5% at 550 nm with a ±3 V applied potential for coloring/bleaching) and fast coloring/bleaching times (13.5/7.5 s). This work provides a facile approach for preparing high-performance materials for a variety of eco-friendly applications.