Amorphous iron oxides anchored on BiOCl nanoplates as robust catalysts for high-performance photo-Fenton oxidation

Semiconductor supported iron oxides are highly promising catalysts to remove organic pollutants in photo-Fenton. Development of robust composite catalysts with both high activity and stability is essential. In this work, amorphous iron oxide layers are uniformly and tightly anchored on two-dimensional (2D) BiOCl nanoplates through post precipitation-deposition and subsequent low-temperature thermal treatment at 150-350 degrees C. A low iron loading amount (1-2 wt.%) is sufficient to make the resulted composite (BiOCl-Fe) catalysts superior in photo-Fenton oxidation of phenol (10 mg/L) with high mineralization efficiency (up to about 80% in 60 min). The low-temperature thermal treatment can significantly enhance the stability of catalysts with much less iron leached and high photo-Fenton performance maintained. The intimate contact between the amorphous iron oxide layers and the 2D BiOCl nanoplates could guarantee the fluent electron transfer and efficient activation of H2O2 at interfaces. Compared with the pristine BiOCl, the BiOCl-Fe catalysts possess faster separation of the charge carriers. The predominant active species turns from O-2(center dot-) in photocatalysis to HO center dot in the photo-Fenton catalysis. This research could provide enhanced understanding on the synthesis of robust catalysts and the structure optimization of BiOCl supported iron oxides for photo-Fenton. (C)& nbsp;2022 Elsevier Inc. All rights reserved.

Automated summary

This study developed a robust composite catalyst consisting of two-dimensional BiOCl nanoplates and amorphous iron oxide layers, which exhibited high activity and stability in the photo-Fenton oxidation of phenol. The catalyst showed efficient mineralization of phenol with a low iron loading amount and maintained high performance and stability after low-temperature thermal treatment.