Photocatalytic hydrogen production, dye degradation, and antimicrobial activity by Ag-Fe co-doped TiO2 nanoparticles

Exploring the highly stable and active photocatalysts for dye degradation, antimicrobial activity, and hydrogen production in visible light has attracted much attention. Herein, Ag, Fe co-doped TiO2 nanoparticles were prepared via a simple sol–gel method. The structural, morphological, and optical properties of the nanoparticles were characterized by various scientific techniques. X-ray diffraction patterns (XRD) and Raman study both verify the mixed phase of TiO2 in FAT_0.25:2. The morphology and purity of co-doped photocatalyst were confirmed by the FE-SEM and EDAX analysis respectively. The surface composition and elemental states of the Ag, Fe, Ti, and O were studied by the XPS spectra. The HR-TEM micrograph displays the majority of spherical nanoparticles within the range of 10–22 nm. The synergistic effect of Ag and Fe narrowed the band gap of TiO2 nanoparticles and surface plasmon resonance (SPR) induced by Ag on the TiO2 surface significantly block the photoexcited electrons and delayed the electron-hole pair recombination rate. The optimized dose of FAT_0.25:2 exhibits an increase in the degradation efficiency of MB dye in the visible light irradiation compared to the pristine TiO2. Besides this, photocatalyst exhibits antimicrobial activity against the S. aureus and E. coli. Furthermore, after 5 h of visible light irradiation, FAT 0.25:2 photocatalyst produces 2377.82 µmol/g of hydrogen gas from the water splitting. The possible reaction mechanism during the photocatalytic activity of FAT_0.25:2 nanoparticle is discussed.