Bromine Ion-Intercalated Layered Bi 2 WO 6 as an Efficient Catalyst for Advanced Oxidation Processes in Tetracycline Pollutant Degradation Reaction.

The visible-light-driven photocatalytic degradation of pharmaceutical pollutants in aquatic environments is a promising strategy for addressing water pollution problems. This work highlights the use of bromine-ion-doped layered Aurivillius oxide, Bi 2 WO 6 , to synergistically optimize the morphology and increase the formation of active sites on the photocatalyst's surface. The layered Bi 2 WO 6 nanoplates were synthesized by a facile hydrothermal reaction in which bromine (Br - ) ions were introduced by adding cetyltrimethylammonium bromide (CTAB)/tetrabutylammonium bromide (TBAB)/potassium bromide (KBr). The as-synthesized Bi 2 WO 6 nanoplates displayed higher photocatalytic tetracycline degradation activity (~83.5%) than the Bi 2 WO 6 microspheres (~48.2%), which were obtained without the addition of Br precursors in the reaction medium. The presence of Br - was verified experimentally, and the newly formed Bi 2 WO 6 developed as nanoplates where the adsorbed Br - ions restricted the multilayer stacking. Considering the significant morphology change, increased specific surface area, and enhanced photocatalytic performance, using a synthesis approach mediated by Br - ions to design layered photocatalysts is expected to be a promising system for advancing water remediation.