Three-dimensional covalent organic framework with tty topology for enhanced photocatalytic hydrogen peroxide production

Despite tremendous progress made in the field of three-dimensional covalent organic frameworks (3D COFs) over the past decade, the construction of high connectivity (>6) 3D COFs with unprecedented topologies remains significant challenge due to the limited availability of high-connectivity building units. Herein, we designed and synthesized of octa-aldehyde difluorobenzene monomer as 8‑connected cubic node for the construction of 3D COF (COF-NUST-16) with tty topology via a bottom-up [8 + 4] reticular strategy for the first time. Attributed to its broad and strong absorption in the visible region, the 8-connectivity 3D COF displays high photocatalytic activity, which was used for photocatalytic production of hydrogen peroxide with high production rate (1081 μmol g−1h−1), and the photocatalytic activity of COF-NUST-16 was 4-fold higher than 2D COF with similar chemical structure. This work not only enriches the topological diversity of COFs, but also paves the way for the application exploration of 3D COFs.