Fig. 5: A comparison of the electronic density of state in Ti-MIL-125 and Zr-UiO-66, and their aminated derivatives.
From: Ligand field tuning of d-orbital energies in metal-organic framework clusters
Conduction band engineering d0-MOFs using linker amination. a The density of states of reveals UiO-66 is type I with a VBM and CBM defined by organic orbitals. The Zr dxy orbitals are 2.0 eV positive of the CBM in non-functionalized UiO-66, sitting at ~−0.75 eV. Amination moves the Zr orbitals 250 meV more positive. b MIL-125 is type IV with a VBM and CBM defined by linker and metal orbitals, respectively. The Ti dxy orbitals shift 100 meV more positive with amination. In both cases, the aminated MOF features a reduced band gap by >1.0 eV. In the UiO-66 series, the ligand-to-metal transition (VBM-to-green band) shifts from 6.2 to 4.5 eV upon the addition of –NH2. The workfunctions are computed by summing the vertical values provided for each MOF.
