Photocatalytic and Antimicrobial Activities of WO3, NdWO3 and rGO/NdWO3 Nanoparticles for Environmental and Health Applications

This study explores the synthesis of tungsten trioxide (WO3), neodymium-doped WO3 (NdWO3) and reduced graphene oxide/NdWO3 (rGO/NdWO3) composites using a hydrothermal method for efficient photocatalytic degradation of methylene blue dye under natural sunlight. Characterization through XRD, FE-SEM, EDAX, FT-IR, UV-DRS, HR-TEM and XPS techniques confirmed the successful synthesis and structural integrity of the materials. XRD revealed distinct monoclinic and hexagonal structures for WO3 and NdWO3, while the rGO/NdWO3 composite maintained the crystallinity of both phases. UV-DRS analysis demonstrated a reduction in the band gap from 1.81 eV (WO3) to 1.60 eV (rGO/NdWO3), enhancing photocatalytic efficiency. Photocatalytic degradation tests indicated rGO/NdWO3 achieved (89.2%) MB removal, outperforming WO3 (59.4%) and NdWO3 (71.5%). This performance enhancement is attributed to the synergistic interaction between rGO and NdWO3, promoting superior charge separation and electron transfer. The degradation followed pseudo-first-order kinetics with the highest rate constant for rGO/NdWO3 (2.05 × 10–4 min–1). Moreover, antimicrobial assays demonstrated that rGO/NdWO3 exhibited enhanced antibacterial activity against Staphylococcus aureus, Salmonella typhi, Escherichia coli and Vibrio parahaemolyticus, surpassing traditional antibiotics. These findings underscore the potential of rGO/NdWO3 as a multifunctional material for advanced photocatalytic and antimicrobial applications.