Enhanced Photocatalytic Activity of Metal‐Metal‐Nonmetal Multidoped TiO2 Nanoparticles towards Visible Light

AbstractTiO2 is the most important and remarkable material in photocatalytic applications. In the present work, pure and doped TiO2 nanoparticles were fabricated by the sol‐gel synthesis route. The impact of the metal and nonmetal dopants on the performance of the photocatalysts was examined systematically. X‐ray diffraction (XRD) analysis affirmed the existence of anatase and rutile phases in the fabricated nanoparticles. The diffuse reflectance spectroscopy (DRS) analysis confirmed that all doped TiO2 nanoparticles have a lower bandgap than undoped TiO2, and (N, Cu, Ag)‐doped TiO2 nanoparticles having the lowest bandgap (2.38 eV), demonstrating that metal‐metal‐nonmetal multidoping improves TiO2′s sensitivity towards visible light. In comparison to pure and other doped TiO2 nanoparticles, methylene blue (MB) photodegrades at a faster rate (rate constant of 0.04878 min−1) with the highest photocatalytic activity (99.61 % MB degradation) on the surface of (N, Cu, Ag)‐doped TiO2. The photocatalytic activities of TiO2 nanoparticles have been improved by multidoping in the following sequence: TiO2<N‐doped TiO2<(N, Cu)‐doped TiO2<(N, Ag)‐doped TiO2<(N, Cu, Ag)‐doped TiO2.