Enhancement in electrical conductivity of a porous indium based metal-organic framework upon I2 uptake: combined experimental and theoretical investigations

To date, the direct synthesis of conductive metal-organic frameworks (C-MOFs) has been a very challenging task, which limits the applications of MOF materials in the field of electronics. In this study, we have incorporated the guest molecule (iodine) into the micropores of an indium-based MOF, which resulted in an enhancement of electrical conductivity by about a thousandfold. Optical band gap energy was lowered by similar to 58% through this I-2 uptake process. Combined experimental and theoretical studies confirmed the presence of I-2 molecules inside the pore. DFT calculations showed that the dispersive interactions between thiophenedicarboxylate linkers and I-2 facilitate to hold the I-2 unit inside the cavity and give higher binding energy, which give rise to a new pathway for charge transport.