Photoinduced Electron Transfer in a Two-Dimensional Conductive Metal–Organic Framework

Two-dimensional metal–organic frameworks offer a rare combination of porosity and conductivity. However, designing ligands that imbue frameworks with efficient charge transport pathways but also permit further functionalization of the ligand structure is not trivial. Towards this end, we leverage the amphoteric and ambipolar nature of phenanthroimidazole moieties to design ligands in which ionic and electronic states are intertwined. This approach forms the basis for a materials platform that is responsive and provides a mechanism for conductance contrast. We detail the synthesis of a new ligand, H8(BPI-P), and describe its optical and electronic properties. We show that these properties are retained upon incorporation into a 2D framework, Cu2(BPI-P), leading to higher-than-expected electrical conductivity that can be externally modulated. The ligand—a near-perfect rhombus—also enables Lozenge tiling in two dimensions, further identifying symmetry as an emerging means of tuning the properties of 2D framework materials.