Design strategies and photocatalytic applications of 2D sp²c COFs: from broad solar harvesting to sustainable hydrogen production and uranium recovery

Abstract

Photocatalytic resource production, utilizing photo-generated electrons and holes for reactions like water splitting and uranium extraction from seawater, demands materials balancing broad light absorption and efficient charge separation. Two-dimensional sp²-carbon-conjugated covalent organic frameworks (sp²c COFs) emerge as highly promising photocatalysts due to their extended π-conjugation, enabling wide solar spectrum capture (including near-infrared) and enhanced carrier mobility. Current design strategies focus on incorporating photosensitive groups, constructing donor-acceptor heterojunctions, and optimizing high-conjugation to boost light harvesting and suppress charge recombination. Furthermore, designing specific active sites is also crucial for photocatalytic uranium extraction from seawater. This review summarizes the characteristics of different two dimensional sp²c COFs and their photocatalytic applications in photocatalytic hydrogen production and uranium recovery. Finally, it outlines future development trajectories for advancing sp²c COFs in sustainable photocatalysis.

Graphical abstract

Keywords

covalent organic framework / conjugated organic polymer / photocatalysis / photocatalytic hydrogen production / uranium extraction from seawater

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