A Squaraine‐Linked Mesoporous Covalent Organic Framework

π in the sky: A squaraine-linked, conjugated two-dimensional porphyrin covalent organic framework (COF; see scheme; C: gray, H: white, N: blue, Cu: red) was synthesized. Owing to the π-conjugated linkage together with the eclipsed stacking of the units, this COF exhibits enhanced chemical and thermal stabilities. It absorbs a broad range of light, from the ultraviolet to the visible, and near-infrared regions, and shows potential as a photocatalyst.