Photocatalytic Performance of Different Copper(I) Iodide Cluster MOFs in Radical Decarboxylative Cyanation

Metal-organic frameworks (MOFs) provide an ideal platform for solar-to-chemical energy conversion but are often limited by rapid charge recombination and insufficient light-harvesting capabilities. Herein, we report a series of MOFs with superior photocatalytic performance by employing a triphenylamine-derived ligand, 4-(4-pyridinyl)-N,N-bis[4-(4-pyridinyl)phenyl]benzenamine (TPPA), as the organic linker. Through modulation of the synthesis conditions, three distinct framework structures were obtained, featuring varied copper(I) iodide cluster nodes ([Cu₄I₄], [Cu₂I₂], and a mixed-cluster system). The photocatalytic performance of these MOFs was systematically evaluated using a radical decarboxylative cyanation reaction as a model transformation. Our results demonstrate that the nuclearity and connectivity of the copper iodide clusters critically influence the framework topology, band alignment, and charge separation efficiency, thereby governing the overall catalytic activity. This work highlights a rational design strategy for engineering MOF-based photocatalysts with precisely tunable active sites and enhanced performance through controlled cluster assembly.