Facile fabrication of novel Z-scheme g-C3N4 nanosheets/ Bi7O9I3 photocatalysts with highly rapid photodegradation of RhB under visible light irradiation

A simple and economical hydrothermal method has efficiently been utilized in the fabrication of a novel C3N4 nanosheet/Bi7O9I3 Z-scheme heterojunction. The synthesis process was carried out under ordinary temperature and pressure without any poisonous ingredients. Different techniques, such as EDX, XRD, FESEM, FTIR, UV-Vis, DRS, PL, and BET, were employed to analyze the as-prepared nanocomposite. To evaluate the photocatalytic activity, degradation of several cationic and anionic organic dyes, i.e., Rhodamine B (RhB), Congo red (CR), and malachite green (MG), under visible light irradiation was investigated. Among the Synthesized binary nanocomposites, the g-C3N4 nanosheet/Bi7O9I3 (15%) demonstrated a superlative efficient photocatalytic performance toward photodegradation of the above-mentioned organic dyes. The results exhibited that 94% of Rhodamine B was decomposed within 20 min by the photodegradation process. These results are due to the reduction of the recombination rate of electron-hole pairs, broadening the visible light harvesting, and improving the photocatalytic yield of graphite carbon nitride. According to the presented data and results, a probable mechanism is suggested. Also, the OH radicals were determined as the main reactive species involved in the degradation reaction. This work presents a novel, recyclable, and high-efficiency Z-scheme heterostructure photocatalyst that may provide a more promising approach for environmental restoration.