Topological Control of Dual Protonic–Electronic Conduction in Metal–Organic Frameworks

High Resolution Image Download MS PowerPoint Slide Metal–organic frameworks (MOFs) with intrinsic dual proton–electron conductivity are highly desirable for energy conversion devices and chemical separation, yet merging these properties within a single crystalline phase remains a challenge. Here, we report two novel Mn(II)-based conjugated MOFs that share similar building blocks, but diverge into distinct topologies: a kagome lattice ( kgm ) and an unprecedented pseudo bex-d topology (Mn-HHTP- bex-d ). These frameworks exhibit sharply contrasting conduction profile: Mn-HHTP - kgm demonstrates excellent electronic conductivity (8.4 × 10 –1 S cm –1 at room temperature), but limited proton transport (3.6 × 10 –7 S cm –1 ) at 98% relative humidity (RH), whereas the pseudo bex-d topology exhibits more balanced electronic conductivity (2.4 × 10 –5 S cm –1 ) and proton conductivity (4.5 × 10 –5 S cm –1 at 98% RH). Crystallographic and computational studies indicate that the efficient π–π stacking in kgm topology promotes charge delocalization and through-space charge transport for electrical conduction, while the pseudo bex-d topology leverages framework-incorporated water molecules and acetate moieties to establish efficient hydrogen-bonding networks for proton transport. This work highlights the critical role of topological control in modulating mixed-conduction properties and offers valuable insights for designing multifunctional MOFs for ambipolar devices, bioelectronics, and energy systems.