Preparation of α-MnO₂-BiOBr composite catalyst and application for efficient degradation of CR in wastewater

Herein, a series of α-MnO 2 -BiOBr (MB) composite catalysts with varying α- MnO 2 , doping levels were successfully synthesized via a facile chemical precipitation method. Comprehensive characterization of the catalysts' morphology, structural features, and surface attributes was conducted. SEM observations confirmed a flower-like architecture interlaced with nanowires in the MB composites. Assessment of catalytic efficacy toward Congo red (CR) and diverse dyes identified 12%-MB as the most active formulation, attaining near-complete elimination (≈100%) of low-concentration CR within 10 minutes. (Co≤50 mg/L). Likewise, the 12%-MB also displayed excellent reusability, for which the degradation rate maintained 99% after ninth cycles.