Metal–Organic Cages with {SiW9Ni4} Polyoxotungstate Nodes

Abstract A tritopic, Ni‐substituted Keggin cluster, {SiW 9 Ni 4 }, assembles with rigid dicarboxylate linkers to give rise to a set of discrete, POM 2 n L 3 n ‐type structures (POM={SiW 9 Ni 4 }) with defined interior voids. The outcome of coordination‐driven self‐assemblies of these polyhedral cages—from fused dimers to trigonal prisms—was found to be sensitive to bend angles of the ditopic ligands, which vary from 122° to 180°. These polyoxotungstate‐based metal–organic polyhedra, when coupled with [Ru(bpy) 3 ]Cl 2 as a photosensitizer and triethanolamine as the electron donor, serve as highly effective catalysts for CO 2 reduction, with turnover numbers up to 328 and CO selectivity as high as 96.2 %. The inner cavities of such cage structures, if functionalized or of sufficient size to encapsulate targeted guest molecules, could present a new strategy towards functional materials for potential applications.