Fabrication of TiO₂/CoMoO₄/PANI nanocomposites with enhanced photocatalytic performances for removal of organic and inorganic pollutants under visible light

Ternary photocatalysts with superior visible-light photocatalytic performances, were fabricated for the first time through integration of CoMoO₄ and polyaniline (PANI) with TiO₂. These photocatalysts were studied by XRD, EDX, SEM, HRTEM, XPS, BET, PL, UV–vis DRS, and FT-IR. The ternary nanocomposites showed a significantly great efficiency for photocatalytic degradation of Rhodamine B (RhB), methyl orange (MO), methylene blue (MB) and fuchsine, as organic pollutants, and photoreduction of Cr(VI), as an inorganic pollutant, in the presence of visible-light illumination, when compared with TiO₂ and TiO₂/CoMoO₄ samples. The photodegradation efficiency of RhB over the TiO₂/CoMoO₄/PANI (30%) photocatalyst was 21.7 and 4.9-folds as high as the pure TiO₂ and TiO₂/CoMoO₄ (30%) nanocomposite, respectively. Moreover, the as-synthesized TiO₂/CoMoO₄/PANI (30%) nanocomposite exhibited considerable photocatalytic activity in reduction of Cr(VI), which is 13.8 and 4.9-folds as high as the TiO₂ and TiO₂/CoMoO₄ (30%) samples, respectively. Pursuant to the results, ^•O₂ ⁻ played critical role during the photocatalytic elimination of RhB. Furthermore, the ternary nanocomposite showed high photocatalytic stability. The present work provides a new approach to design ternary visible-light photocatalysts based on TiO₂ with enhanced performances for water purifications.