Synergistic photocatalytic performance of n-Fe2O3/p-NiO heterojunctions under visible light

A p-n heterojunction based on n-Fe2O3/p-NiO 2 O 3 /p-NiO thin films was synthesized by the sol-gel method with the objective of developing a highly efficient visible light photocatalyst. The phase and surface microstructures of the heterostructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Spectroscopic and photocatalytic analyses were performed using a UV-Vis spectrophotometer. Comparative studies revealed that the Fe2O3/NiO 2 O 3 /NiO heterojunction exhibited superior photodegradation of methylene blue (MB) under visible light irradiation compared to single Fe2O3 2 O 3 and NiO photocatalysts. The photodecomposition efficiency of methylene blue (MB) was approximately 70 %, 81.43 %, and 97.92 % in the presence of NiO, Fe2O3, 2 O 3 , and Fe2O3/ 2 O 3 / NiO films, respectively. In addition, a potential photocatalytic mechanism for the Fe2O3/NiO 2 O 3 /NiO heterojunction was proposed to elucidate the enhanced degradation of MB. The synergistic effects between Fe2O3 2 O 3 and NiO in the heterojunction facilitate efficient charge separation and transfer, resulting in enhanced photocatalytic activity.