Structural engineering of <scp> Bi ₂ S ₃ </scp> @ <scp>MIL</scp> ‐100 nanocomposite for the efficient photocatalytic degradation of bromophenol blue

Abstract Metal–organic frameworks (MOFs) have gained a lot of attention as an emerging photocatalyst because of their distinct features. In this study, an innovative hybrid photocatalyst was created by combining Bi 2 S 3 and MIL‐100(Fe) to form Bi 2 S 3 @MIL‐100 nanocomposite using a simple hydrothermal approach. A variety of characterization methods like FTIR, XRD, scanning electron microscope (SEM), and EDX spectroscopy were employed to describe the materials that were synthesized. The degradation efficiency of Bi 2 S 3 , MIL‐100, and Bi 2 S 3 @MIL‐100 nanocomposites was determined using UV–Vis spectroscopy under various circumstances such as pH and contact time for the removal of bromophenol blue (BPB). The nanocomposite showed 97% degradation efficiency for the time of 80 min to remove BPB. To better understand dye photodegradation, the Langmuir–Hinshelwood model was applied to experimental data. Experiments using trapping showed that the superoxide radicals (O₂• − ) are the main active species in charge of the photodegradation of bromophenol blue over Bi 2 S 3 @MIL‐100, while hydroxyl radicals (•OH) and holes (h + ) play secondary roles. This implies that the process of degradation is mainly governed by reactive oxygen species (ROS) rather than direct oxidation by photo‐generated holes. The Bi 2 S 3 @MIL‐100 nanocomposite exhibited excellent stability and reusability, maintaining high photodegradation efficiency over four consecutive cycles.