Construction of S-scheme MIL-101(Fe)/Bi2MoO6 heterostructures for enhanced catalytic activities towards tetracycline hydrochloride photodegradation and nitrogen photofixation

This study reported the construction and photocatalytic applications of S-scheme MIL-101(Fe)/Bi₂MoO₆ heterostructures via a solvothermal reaction. The morphologies and microstructures of these heterostructures were comprehensively studied. The heterostructures exhibited enhanced photocatalytic activities towards tetracycline hydrochloride (TCH) photodegradation and nitrogen photofixation compared with the corresponding single components. Approximately 96.2% of TCH can be removed using the MIL-101(Fe)/Bi₂MoO₆(2:1) heterostructure at the optimized component ratio. Moreover, the resultant MIL-101(Fe)/Bi₂MoO₆(2:1) heterostructure demonstrated considerably enhanced photocatalytic activity towards nitrogen photofixation, and the produced NH₄⁺ concentration reached up to (0.836 ± 0.057) mg·L⁻¹ without the addition of any sacrificial agents. The improved photocatalytic activities of MIL-101(Fe)/Bi₂MoO₆ heterostructures can be attributed to the enhanced surface areas, effective charge separation and the development of S-scheme heterostructures between Bi₂MoO₆ and MIL-101(Fe). This research thus offers helpful insight into the fabrication of S-scheme systems for photocatalytic applications.