Integration of oxygen vacancy rich-TiO2 with BiOI and Ag6Si2O7: Ternary p-n-n photocatalysts with greatly increased performances for degradation of organic contaminants

Abstract Photocatalysis process is a prominent approach for the degradation of organic contaminants. However, the swift recombination of charge carriers commonly limits the photoactivity. Hence, to create a suitable nanocomposite for removal of pollutants, BiOI and Ag6Si2O7 particles were anchored on the oxygen vacancy rich-TiO2 (abbreviated as OVs-TO) through a simple approach to construct the OVs-TO/BiOI/Ag6Si2O7 nanocomposites. Then, various structural features of the systems were assayed with different characterization tools. It was found that the photocatalyst with 20 wt% and 30 wt% of BiOI and Ag6Si2O7 exhibits the excellent performance in removal of RhB, which are about 194, 18.1, and 9.59-times higher than the TiO2 (abbreviated as TO), OVs-TO, and OVs-TO/BiOI (20 %) nanomaterials, respectively. This supreme improved photodegradation activity was allocated to the formed p-n-n heterojunctions between the semiconductors, impressive segregation of charges, significant visible-light absorption of OVs-TO, BiOI, and Ag6Si2O7, and textural enhancement. A suitable mechanism was also offered through the outcomes of Mott-Schottky and the quenching experiments. This research work illustrated that the ternary p-n-n photocatalyst could be efficacious for ameliorating the visible-light photocatalytic ability for environmental and energy applications.