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The ultrafast transient dynamics of a free-base tetraphenylporphyrin (H2TPP) surface-mounted metal organic framework (SURMOF) is spectroscopically characterized and compared with that of H2TPP in ethanol solution. A dramatic increase of the quantum yield of the Soret band fluorescence (S-2 -> S-0) is observed in the H2TPP-SURMOF, which is accompanied by an increase of the S-2 fluorescence lifetime and a broadening of the fluorescence spectra. In contrast, the Q band (S-1) fluorescence is strongly quenched in the H2TPP SURMOF compared with the fluorescence of H(2)TPPin ethanol solution. The observed transient absorption kinetics supports the fluorescence data. The enhanced fluorescence in the SURMOF compared with H2TPP in solution is attributed to the combination of two factors: the alignment of the vibrational energy levels of the dominant Franck-Condon active mode of the Soret and Q bands and the weaker coupling of these modes to the environment., QC 20181106

Ordered porphyrin-based metal organic frameworks (MOFs) may serve as a model for mimicking the natural photosynthesis with highly ordered chlorophylls, i.e., porphyrin-like chromophores. Study of light harvesting and energy transfer as the primary event of photosynthesis is of great importance leading to improvement of photovoltaics overall performance. Detailed characterization of ultrafast dynamics of zinc tetraphenylporphyrin (ZnTPP) surface mounted metal organic framework (SURMOF) is reported by using various steady-state and time-resolved laser spectroscopic techniques, i.e., time correlated single photon counting, fluorescence up-conversion and transient absorption pump-probe with 20 fs resolution. Obtained results in these nanoporous materials were compared with corresponding results for ZnTPP in ethanol measured under the same conditions. Dramatic quenching of both upper excited singlet state S-2 and first excited state SI was observed. Subpicosecond and picosecond lifetimes were detected in transient fluorescence and absorption. Analytical formulas are derived for the linear absorption, steady-state fluorescence, and fluorescence up-conversion signals. Theoretical description excellently reproduces experimental time and frequency resolved signals. Strong quenching of the femtosecond transients in SURMOF is explained in terms of highly efficient Forster resonance energy transfer between the neighboring porphyrin moieties which is caused by a strong spectral overlap of absorption and steady-state fluorescence spectra and quantum coherent energy transfer and redistribution., QC 20180205

We report a new triplet-triplet annihilation photon up-conversion (TTA-UC) system using an epitaxial Zn-perylene surface-supported metal-organic framework (SURMOF) grown on metal oxide surface as "emitter", and a platinum octaethylporphyrin (PtOEP) as "sensitizer" in [Co(bpy)(3)](2+/3+) acetonitrile solution. It has been demonstrated that the photocurrent can be significantly enhanced relative to epitaxial Zn-perylene SURMOF due to the TTA-UC mechanism. This initial result holds promising applications toward SURMOF-based solar energy conversion devices., QC 20211022

A monolithic, highly electrochemically efficient Re-based metal-organic framework (MOF) thin film has been deposited onto a conductive FTO electrode by liquid-phase epitaxy. The X-ray diffraction (XRD) analysis reveals the presence of a highly oriented film grown exclusively along the [001] direction. This epitaxially-grown SURMOF exhibits an extremely high faradaic efficiency of 93 +/- 5% when operated as an electrocatalyst for the reduction of CO2 to CO. In addition, the obtained current densities of the high-quality monolithic coatings exceed 2 mA cm(-2), a value at least one order of magnitude larger than that reported for previous electrocatalytically active MOF thin films., QC 20161117