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Photoconductivity is a characteristic property of semi-conductors. Herein, we present a photo-conducting crystalline metal-organic framework (MOF) thin film with an on-off photocurrent ratio of two orders of magnitude. These oriented, surface-mounted MOF thin films (SURMOFs), contain porphyrin in the framework backbone and C 60 guests, loaded in the pores using a layer-by-layer process. By comparison with results obtained for reference MOF structures and based on DFT calculations, we conclude that donor-acceptor interactions between the porphyrin of the host MOF and the C 60 guests give rise to a rapid charge separation. Subsequently, holes and electrons are transported through separate channels formed by porphyrin and by C 60 , respectively. The ability to tune the properties and energy levels of the porphyrin and fullerene, along with the controlled organization of donor-acceptor pairs in this regular framework offers potential to increase the photoconduction on-off ratio., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A ruthenium complex, porphyrin sensitizer, fullerene acceptor molecular pentad has been synthesized and a long-lived hole-electron pair was achieved in aqueous solution by photoinduced multistep electron transfer: Upon irradiation by visible light, the excited-state of a zinc porphyrin ( 1 ZnP*) was quenched by fullerene (C 60 ) to afford a radical ion pair, 1,3 (ZnP .+ -C 60 .- ). This was followed by the subsequent electron transfer from a water oxidation catalyst unit (Ru II ) to ZnP .+ to give the long-lived charge-separated state, Ru III -ZnP-C 60 .- , with a lifetime of 14 μs. The ZnP worked as a visible-light-harvesting antenna, while the C 60 acted as an excellent electron acceptor. As a consequence, visible-light-driven water oxidation by this integrated photosynthetic model compound was achieved in the presence of sacrificial oxidant and redox mediator., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A phosphole-fused porphyrin dimer, as a representative of a new class of porphyrins with a phosphorus atom, was synthesized for the first time. The porphyrin dimer exhibits remarkably broadened absorption, indicating effective π-conjugation over the two porphyrins through the phosphole moiety. The porphyrin dimer possesses excellent electron-accepting character, which is comparable to that of a representative electron-accepting material, [60]PCBM. These results provide access to a new class of phosphorus-containing porphyrins with unique optoelectronic properties., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The unprecedented dependence of final charge separation efficiency as a function of donor-acceptor interaction in covalently-linked molecules with a rectilinear rigid oligo-p-xylene bridge has been observed. Optimization of the donor-acceptor electronic coupling remarkably inhibits the undesirable rapid decay of the singlet charge-separated state to the ground state, yielding the final long-lived, triplet charge-separated state with circa 100% efficiency. This finding is extremely useful for the rational design of artificial photosynthesis and organic photovoltaic cells toward efficient solar energy conversion., (© 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.)

Controlling cell functions using external photoresponsive nanomaterials has enormous potential for the development of cell-engineering technologies and intractable disease therapies, but the former currently requires genetic modification of the target cells. We present a method using plasma-membrane-targeted gold nanorods (pm-AuNRs) prepared with a cationic protein/lipid complex to activate a thermosensitive cation channel, TRPV1, in intact neuronal cells. Highly localized photothermal heat generation mediated by the pm-AuNRs induced Ca(2+) influx solely by TRPV1 activation. In contrast, the use of previously reported cationic AuNRs that are coated with a conventional synthetic polymer also led to photoinduced Ca(2+) influx, but this influx resulted from membrane damage. Our method provides an optogenetic platform without the need for prior genetic engineering of the target cells and might be useful for novel TRPV1-targeted phototherapeutic approaches., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A tropolone group has been employed for the first time as an anchoring group for dye-sensitized solar cells (DSSCs). The DSSC based on a porphyrin, YD2-o-C8T, with a tropolone moiety exhibited a power-conversion efficiency of 7.7 %, which is only slightly lower than that observed for a reference porphyrin, YD2-o-C8, with a conventional carboxylic group. More importantly, YD2-o-C8T was found to be superior to YD2-o-C8 with respect to DSSC durability and binding ability to TiO2 . These results unambiguously demonstrate that tropolone is a highly promising dye-anchoring group for DSSCs in terms of device durability as well as photovoltaic performance., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A profusion of phospholes: Diacenaphtho[1,2-b:1',2'-d]phospholes, a new class of arene-fused phosphole π-systems, were synthesized and their structural and electrochemical properties studied. The P-sulfide derivative has a high electron-transporting ability (μ(E) =2.4×10(-3) cm(2) V(-1) s(-1)) in a vacuum-deposited film., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Mind the (narrow) gap: Alpha-ethynylphospholes generated in situ from the corresponding silyl-capped precursors were converted into a series of alpha-(arylethynyl) phospholes bearing functional substituents as well as an alpha,alpha'-linked terphosphole (see scheme). The terphosphole has a narrow HOMO-LUMO gap owing to efficient pi conjugation over the three phosphole rings.