Constructing a High-Efficiency MoO₃/Polyimide Hybrid Photocatalyst Based on Strong Interfacial Interaction

A novel two-dimensional hybrid polymer photocatalyst black-MoO₃/polyimide was synthesized by one-pot thermopolymerization of monomers, ammonium molybdate, and thiourea at mild temperatures. Thiourea and ammonium molybdate as fluxing agents promote the formation of black molybdenum oxide (BMO) on polyimide (PI) and enhance the crystallinity of PI. It is confirmed by X-ray photoelectron spectroscopy, electron paramagnetic resonance, and Fourier transform infrared that the strong interaction between BMO and PI leads to the formation of a Mo–N coordination bond through the coordination of N atoms of heptazine units to the unsaturated Mo atoms of BMO and results in a large number of Mo⁵⁺ cations in BMO/PI. UV–vis and photoluminescence reveal that the visible light absorption of BMO/PI was increased and the separation efficiency of photogenerated electron/hole obviously was significantly enhanced, which facilitates the improvement of the photocatalytic activity of BMO/PI. This work provides a new approach to synthesizing efficient inorganic–organic hybrid semiconductor photocatalysts.