Simultaneous photocatalytic hydrogen peroxide production and pollutant degradation via bipyridine-based polyimide covalent organic framework

Covalent organic framework (COF) photocatalysts for hydrogen peroxide (H₂O₂) production are receiving significant attention because of the ever-increasing demand for H₂O₂. Despite the redox-active property and notable photophysical characteristics of polyimide (PI), the potential of PI-based COFs (PICs) for photocatalytic H₂O₂ production remains unexplored. Herein, we present a dual redox-active bipyridine-containing PIC (PIC-BPY) as an efficient photocatalyst for H₂O₂ production. PIC-BPY demonstrated exceptional performance by achieving an H₂O₂ production rate of 2772 μmol g_cat.⁻¹, which is three times higher than its biphenyl-based counterpart. We elucidated the reaction pathway through a series of scavenger tests and electron spin resonance analysis, thereby confirming the additional active role of BPY along with that of PIC framework. Furthermore, we harnessed hydroxyl radicals generated during photocatalysis to explore the potential of PIC-BPY for concurrent pollutant degradation and H₂O₂ production.