Conductive metal-organic frameworks (c-MOFs) have drawn increasing attention for their outstanding performance in energy-related applications. However, the majority of reported c-MOFs are based on 2D structures. Synthetic strategies for 3D c-MOFs are under-explored, leaving unrealized functionality in both their structures and properties. Herein we report Zn-HAB, a 3D c-MOF comprised of hexaaminobenzene and Zn(II). Zn-HAB is shown to have microporosity with a band gap of approximately 1.68 eV, resulting in a moderate conductivity of 0.86 mS cm(-1) and a high Seebeck coefficient of 200 mu V K-1 at 300 K. The power factor of 3.44 nW m(-1) K-2 constitutes the first report of the thermoelectric properties of an intrinsically conductive 3D MOF.

Redox-active organic materials have gained growing attention as electrodes of rechargeable batteries. However, their key limitations are the low electronic conductivity and limited chemical and structural stability under redox conditions. Herein, we report a new cobalt-based ;2D conductive metal-organic framework (MOF), Co-HAB, having stable, accessible, dense active sites for high-power energy storage device through conjugative coordination between a redox-active linker, hexaaminobenzene (HAB), and a Co(II) center. Given the exceptional capability of Co-HAB for stabilizing reactive HAB, a reversible three-electron redox reaction per HAB was successfully demonstrated for the first time, thereby presenting a promising new electrode material for sodium-ion storage. Specifically, through synthetic tunability of Co-HAB, the bulk electrical conductivity of 1.57 S cm(-1) was achieved, enabling an extremely high rate capability, delivering 214 mAh g(-1) within 7 min or 152 mAh g(-1) in 45 s. Meanwhile, an almost linear increase of the areal capacity upon increasing active mass loading up to 9.6 mg cm(-2) was obtained, demonstrating 2.6 mAh cm(-2) with a trace amount of conducting agent.

Conductive metal-organic frameworks (c-MOFs) have shown outstanding performance in energy storage and electrocatalysis. Varying the bridging metal species and the coordinating atom are versatile approaches to tune their intrinsic electronic properties in c-MOFs. Herein we report the first synthesis of the oxygen analog of M-3(C6X6)(2) (X = NH, S) family using Cu(II) and hexahydroxybenzene (HHB), namely Cu-HHB [Cu-3(C6O6)(2)], through a kinetically controlled approach with a competing coordination reagent. We also successfully demonstrate an economical synthetic approach using tetrahydroxyquinone as the starting material. Cu-HHB was found to have a partially eclipsed packing between adjacent 2D layers and a bandgap of approximately 1 eV. The addition of Cu-HHB to the family of synthetically realized M-3(C6X6)(2) c-MOFs will enable greater understanding of the influence of the organic linkers and metals, and further broadens the range of applications for these materials.