α-Fe₂O₃-based nanocomposites: synthesis, characterization, and photocatalytic response towards wastewater treatment

Recently, rising distress over ecological pollution owing to water contamination by coloring effluents primarily due to dyes is of growing concern. The development of semiconductor/magnetic oxide-based nanomaterials has verified to be a potent remediation means for water pollution. In the present article, the fabrication of nanocomposites was carried out by the facile hydrothermal method. The ZnO and ZnSe nanoparticles were in situ formed on the α-Fe₂O₃ layer, thereby forming a heterojunction. The prepared α-Fe₂O₃/ZnSe nanocomposite possessed a degradation of 98.9% for a Congo red aqueous solution of 100 ppm. The α-Fe₂O₃/ZnO nanocomposite showed only 26% degradation of 100 ppm dye solution depicting a poor photocatalytic performance. This is attributed to the formation of recombination-enhanced configuration (type-I heterostructure) in the α-Fe₂O₃/ZnO nanocomposite (NC). In contrast, α-Fe₂O₃/ZnSe NC accomplished a higher and enhanced photocatalytic response. The key rationale for elevated photocatalytic response is the establishment of a recombination-free configuration (type-II heterostructure). Thus, α-Fe₂O₃/ZnSe NC known as one of outstanding nanoparticle-nanocomposite photocatalysts was synthesized under mild conditions exclusive of some multifaceted post-treatment, for dye abatement process.