Preferentially oriented m-tuned WO3 thin-films photocatalysts for the multitargeted degradation of organic molecules

In this work, morphology-tuned tungsten oxide (m-tuned WO₃) thin films are deposited on a glass substrate by a simple and cost-effective chemical bath deposition (CBD) method. The deposition pH is varied to tune the physicochemical properties of m-tuned WO₃ thin films. The m-tuned WO₃ thin films show an orthorhombic crystal structure with a preferred orientation along the (020) plane. The morphological study demonstrated the conversion of ‘rice hull’ to ‘interlocked nanosheets’ to ‘reticulated nanosheets composed of nanorods’ upon changing pH, highlighting the significant role of pH in m-tuned WO₃ thin film synthesis. The m-tuned WO₃ thin films show good absorption in the visible-light region (390–780 nm) of the solar spectrum. The m-tuned WO₃ thin films are used for the visible light active photocatalytic degradation of organic molecules such as methylene blue (MB), rhodamine B (Rh B), and tetracycline hydrochloride (TC). The optimized m-tuned WO₃ thin film shows maximum photocatalytic performance of 95, 94, and 86 % in 180 min for MB, Rh B, and TC, respectively. The present study demonstrates the usefulness of the CBD method for the deposition of m-tuned WO₃ and improved photocatalytic performance.