One-dimensional covalent organic frameworks with atmospheric water harvesting for photocatalytic hydrogen evolution from water vapor

Photocatalytic hydrogen evolution from water vapor presents a novel approach to solar energy conversion. Nevertheless, the design and synthesis of water-adsorbing photocatalysts is exceedingly challenging. In this report, we for the first time present three hygroscopic one-dimensional (1D) covalent organic frameworks (COFs) based on photosensitive pyrene (Py-MPA, Py-PDCA, and Py-HMPA) combined with atmospheric water harvesting (AWH) and photocatalysis for photocatalytic water vapor splitting. Due to the ultra-small pores of the 1D structure, with hydrophilic -OH sites satisfying the microporous filling of water molecules, Py-HMPA demonstrated superior water adsorption capacity at lower humidity. Remarkably, Py-HMPA exhibited an impressive H2 production rate of 105 μmol g−1 h−1 and high stability during solid-state photocatalysis utilizing water vapor. Overall, this work paves a new pathway of organic porous materials for photocatalytic water vapor splitting.