In this study, synthesis of WO3 nanoparticles (NPs), using the physically clean method known as laser ablation of a tungsten target immersed in distilled water is reported. Fundamental wavelength of an acousto-optically Q-switched Nd:YAG laser with 13, 18, 23 J/cm2 laser fluences was utilized for this purpose. Transmission Electron Microscopy (TEM) associated with Dynamic Light Scattering (DLS) show an increase in average particle size as the laser fluence increases from 13 to 23 J/cm2, also with a precise look into the TEM images, the chains of WO3 NPs are observable although the length of the chains decreases while decreasing the laser fluence. Photocatalytic and antimicrobial activity of the products against E. coli (Escherichia coli) bacteria under UV and visible light illumination were investigated and showed that for photocatalytic and antibacterial processes, active surface area and energy band gap play the main roles while illuminating the nanoparticle samples with UV and visible light, respectively. Moreover, anti-UV properties of the products originated from half harmonic generation process were corroborated by PL (photoluminescence) emission studies.
