We have prepared a push-pull porphyrin with an electron-donating triarylamino group at the β,β'-edge through a fused imidazole group and an electron-withdrawing carboxyquinoxalino anchoring group at the opposite β,β'-edge (ZnPQI) and evaluated the effects of the push-pull structure of ZnPQI on optical, electrochemical, and photovoltaic properties. ZnPQI showed red-shifted Soret and Q bands relative to a reference porphyrin with only an electron-withdrawing group (ZnPQ), thus demonstrating the improved light-harvesting property of ZnPQI. The optical HOMO-LUMO gap was consistent with that estimated by DFT calculations. The ZnPQI-sensitized solar cell exhibited a relatively high power conversion efficiency (η) of 6.8 %, which is larger than that of the ZnPQ-sensitized solar cell (η=6.3 %) under optimized conditions. The short-circuit current and fill factor of the ZnPQI-sensitized solar cell are larger than those of the ZnPQ-sensitized solar cell, whereas the open circuit potential of the ZnPQI-sensitized cell is smaller than that of the ZnPQ-sensitized cell, leading to an overall improved cell performance of ZnPQI. Such fundamental information provides a new tool for the rational molecular design of highly efficient dye-sensitized solar cells based on push-pull porphyrins.

Dense arrays of zinc oxide nanorods with high specific surface areas were grown by hydrothermal method and functionalized by self-assembled monolayer (SAM) of porphyrins. The growth process was optimized to obtain dense arrays of nanorods with diameter of 60–80 nm and length up to 1.5 μm. The increase in the effective surface area was monitored by comparing the absorbances of SAM deposited both on the flat and nanorod surfaces of ZnO. To alter further semiconductor-organic SAM interactions, a 2 or 5 nm thick layer of either Al2O3 or TiO2 was deposited on the ZnO nanorods. The present results show that both carboxylic acid and triethoxysilane anchors can be used to form porphyrin SAMs on the studied metal oxide substrates, and the electronic interactions between the metal oxide and porphyrin SAM are strongly modified by a thin layer of Al2O3 or TiO2. These hybrid semiconductor-organic SAM constructions present promising model systems for advanced spectroscopy studies of semiconductor-organic interfaces with high degree of control over electronic interactions and system morphology.

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The adhesion and contact guidance of human primary osteogenic sarcoma cells (Saos-2) were characterized on smooth, microstructured (MST) and micro- and nano-structured (MNST) polypropylene (PP) and on the same samples with a silicon-doped carbon nitride (C(3)N(4)-Si) coating. Injection molding was used to pattern the PP surfaces and the coating was obtained by using ultra-short pulsed laser deposition (USPLD). Surfaces were characterized using atomic force microscopy and surface energy components were calculated according to the Owens-Wendt model. The results showed C(3)N(4)-Si coated surfaces to be significantly more hydrophilic than uncoated ones. In addition, there were 86% more cells in the smooth C(3)N(4)-Si coated PP compared to smooth uncoated PP and 551%/476% more cells with MST/MNST C(3)N(4)-Si coated PP than could be obtained with MST/MNST uncoated PP. Thus the adhesion, spreading and contact guidance of osteoblast-like cells was effectively improved by combining surface texturing and deposition of osteocompatible C(3)N(4)-Si coating.

Condensation of 1,8-naphthalic anhydride with N,N-(dimethylamino)aniline produced the donor-acceptor compound DMIM, which crystallised from a chloroform–diethyl ether mixture to afford two different coloured crystal polymorphs.