Integration of a (-Cu-S-)n plane in a metal-organic framework affords high electrical conductivity

Designing highly conducting metal-organic frameworks (MOFs) is currently a subject of great interest for their potential applications in diverse areas encompassing energy storage and generation. Herein, a strategic design in which a metal-sulfur plane is integrated within a MOF to achieve high electrical conductivity, is successfully demonstrated. The MOF {[Cu-2(6-Hmna)( 6-mn)]center dot NH4}(n) (1, 6-Hmna = 6-mercaptonicotinic acid, 6-mn = 6-mercaptonicotinate), consisting of a two dimensional (-Cu-S-) n plane, is synthesized from the reaction of Cu(NO3)(2), and 6,6'-dithiodinicotinic acid via the in situ cleavage of an S-S bond under hydrothermal conditions. A single crystal of the MOF is found to have a low activation energy (6 meV), small bandgap (1.34 eV) and a highest electrical conductivity (10.96 S cm(-1)) among MOFs for single crystal measurements. This approach provides an ideal roadmap for producing highly conductive MOFs with great potential for applications in batteries, thermoelectric, supercapacitors and related areas.