TiO2/AgBr Modified with PANI and RGO as a Visible Light-Driven Photocatalyst with Considerably Enhanced Photocatalytic Activity

TiO2/AgBr modified with PANI and RGO as a visible light-driven photocatalyst has been prepared for the first time. The successful formation of nanophotocatalyst and its characteristics were investigated using XRD, EDS, SEM, TEM, FTIR, Raman, UV-vis DRS, and PL. The photocatalytic activity of prepared samples was studied toward the degradation of RhB, MB, and MO under the irradiation of visible light. Based on the results, the photodegradation efficiency of TiO2/AgBr/PANI/RGO nanophotocatalyst was considerably enhanced compared with TiO2, TiO2/AgBr/PANI, and TiO2/PANI/RGO. The corresponding RhB degradation rate constant for TiO2/AgBr/PANI/RGO nanophotocatalyst was 57, 1.4, and 1.8 times higher than that of TiO2, TiO2/AgBr/PANI, and TiO2/PANI/RGO. Synergistic enhancement of photocatalytic degradation on the TiO2/AgBr/PANI/RGO sample was mainly attributed to increasing light absorption and promoting charge separation arising from the formation of a p-n-n heterojunction, as evidenced by the UV-vis DRS and PL spectroscopy. To specify the photocatalytic mechanism, BQ, AO and 2-PrOH were used and (OH)-O-center dot and O-center dot(2)- were determined as the main active species in the photodegradation experiments. Besides, the great photocatalytic stability of the as-prepared TiO2/AgBr/PANI/RGO nanophotocatalyst was disclosed through four consecutive cycling runs.

Automated summary

TiO2/AgBr modified with PANI and RGO as a visible light-driven photocatalyst has shown significantly enhanced photocatalytic activity, with a synergistic enhancement attributed to increased light absorption and promoted charge separation. The formation of a p-n-n heterojunction was identified as a key factor in the improved performance. Additionally, (OH)• and O•2- were determined as the main active species in the photodegradation experiments, highlighting the photocatalytic mechanism involved.