Photoinduced RhB-sensitized effect on a novel AgI/BiOCl/biochar photocatalyst to boost its photocatalytic performance for 17α-ethinyl estradiol degradation

Abstract

In this study, a simple and effective strategy was developed for the synthesis of novel visible-light-active AgI/BiOCl/biochar (AgI/BiOCl/BC) photocatalysts. The addition of rhodamine B (RhB) as a sensitizer was found to considerably enhance the photocatalytic activity of AgI/BiOCl/BC toward the degradation of 17α-ethinyl estradiol (EE2). Furthermore, the incorporation of biochar (BC) into the BiOCl resulted in an increased abundance of free radicals, that could be used for degradation. Additionally, the presence of BC facilitated the separation of carriers by serving as an electron transport channel. The photocatalytic efficiency of the AgI/BiOCl/BC photocatalyst was shown to be highly effective in the degradation of EE2, the degradation efficiency of the AgI/BiOCl/BC was found to be 98.60 % after a 12-min exposure to visible light. Additionally, the photocatalytic activity increased further when RhB sensitization was performed, resulting in a remarkable elimination efficiency of 99.60 % for EE2 after only 4 min of photocatalysis. RhB could not only provide photosensitivity but also degrade along with EE2 as a pollutant, which can be used for the treatments of dyes and EE2 wastewater. The results of photocatalysis investigations indicated that AgI/BiOCl/BC could degrade various dyes, including methyl orange (MO), methylene blue (MB), and congo red (CR). Through the introduction of Ag-based materials, the obtained AgI/BiOCl/BC photocatalyst exhibited significant antibacterial potential against Staphylococcus aureus and Escherichia coli, with antibacterial rates of 99.94 % and 99.99 %, respectively. The cyclic experiment demonstarted that AgI/BiOCl/BC exhibited excellent stability and recyclability. Furthermore, the potential photocatalytic mechanism and degradation pathway were suggested through a combination of experimental findings and theoretical investigations. The obtained AgI/BiOCl/BC photocatalyst is a multifunctional photocatalyst with excellent performance in photocatalytic degradation and sterilization. This photocatalyst is expected to be applied to the treatment of complex pollutant water in the environmental field.