Pyrene-Based Covalent Organic Frameworks for Photocatalytic Hydrogen Peroxide Production.

Four highly porous covalent organic frameworks (COFs) containing pyrene units were prepared and explored for photocatalytic H O production. The experimental studies are complemented by density functional theory calculations, proving that the pyrene unit is more active for H O production than the bipyridine and (diarylamino)benzene units reported previously. H O decomposition experiments verified that the distribution of pyrene units over a large surface area of COFs plays an important role in catalytic performance. The Py-Py-COF though contains more pyrene units than other COFs which induces a high H O decomposition due to a dense concentration of pyrene in close proximity over a limited surface area. Therefore, a two-phase reaction system (water-benzyl alcohol) was employed to inhibit H O decomposition. This is the first report on applying pyrene-based COFs in a two-phase system for photocatalytic H O generation.