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ChemCatChem 2011, 3, 458 -474 through water photolysis and those that produce methanol by CO 2 reduction with the aid of an artificial photosynthesis system. As hydrogen and methanol are low-carbon fuels (the emission of CO 2 from the combustion of these fuels is low), they are considered to be alternatives to fossil resources. In this review, solar fuel production systems consisting of an artificial photosynthesis system, a catalyst, and an enzyme are discussed. These systems are expected to help in reducing CO 2 and to promote the use of low-carbon fuels in the future. Scheme 1. Z Scheme of the natural photosynthesis of higher green plants and oxygenic photosynthetic cyanobacteria.[a] Dr.Scheme 2. Solar hydrogen production or CO 2 photoreduction to low carbon fuels, such as formic acid and methanol by using PSI and PSII in the presence of suitable catalyst.Scheme 3. Artificial photosynthesis system for solar hydrogen production or CO 2 photoreduction to low carbon fuels, such as formic acid and methanol.Scheme 4. Artificial photosynthesis system with visible light irradiation consisting of an electron donor (ED), a photosensitizer (S1), and an electron relay (EC1). 460 www.chemcatchem.org

This paper focuses on an ultrathin polymer optode containing europium complexes (p(DDA-Eu(TTA) 3 Phen)). Ultrathin films were prepared by the Langmuir-Blodgett (LB) technique; a mixed solution of poly-(N-dodecylacrylamide) (pDDA) and tris(4,4,4-trifluoro-1-(2-thienyl)-1,3-butanediono)-1,10-phenanthroline europium(III) (Eu(TTA) 3 Phen) was spread onto a water subphase and the condensed monolayer was transferred onto a solid substrate. The spectroscopic properties and layer structure of p(DDA-Eu(TTA) 3 Phen) LB films were investigated by UV-Vis spectroscopy, fluorescence spectroscopy, time-resolved luminescence decay measurement, X-ray diffraction, and surface plasmon spectroscopy. It was found that europium complexes were uniformly distributed in the ultrathin films compared with a cast film. The p(DDA-Eu(TTA) 3 Phen) optodes showed efficient sensitivity to temperature in the range of 320 to 370 K. The findings demonstrate that the p(DDA-Eu(TTA) 3 Phen) optode is a good candidate for temperature sensitive sensors.

A novel pressure-sensitive luminescent coating on porous anodized aluminium is developed. A method of making the coating is described in detail. The coating is a thin anodized aluminium layer, which is formed onto the surface of aluminium by an electro-chemical process. The luminophore is adsorbed directly onto the surface of the layer via chemical or physical adsorption. This coating is suitable for measuring unsteady pressure fields due to its fast-responding characteristics. The time response of the present coating is evaluated theoretically and experimentally. Four kinds of luminophore, tris(4,7-diphenylphenanthroline)ruthenium(II) ([Ru(dpp) 3 ] 2+ ), tetrakis(4-carboxyphenyl)porphyrin (TCPP), platinum tetrakis(4-carboxyphenyl)porphyrin (PtTCPP), and pyrene butylic acid (PBA), have been tested on their response to a step change in pressure. A pressure jump apparatus and a shock tube were utilized to generate a pressure discontinuity. Some static characteristics were also tested. The theoretical analysis shows that the present coating should have a time response in the order of microseconds due to its porous structure. The time response depends not only on luminescence lifetime, which imposes an ultimate limit on the time response, but also on the thickness of the anodized aluminium layer, because oxygen permeation to the pores existing on the anodized aluminium layer can be described as a diffusive phenomenon. The effective diffusion coefficient is estimated to be approximately 5 × 10 −6 m 2 s −1 . Experimental results show that all the tested coatings except the PtTCPP coating have a response time of less than 1 ms. Only the PBA coating shows a substantial photodegradation. The response time of the [Ru(dpp) 3 ] 2+ coating is longer than 20 µs, and depends on the thickness of the anodized aluminium layer. The response time of the TCPP coating, on the other hand, is less than 10 µs, and is independent of the thickness of the layer. This independence suggests that the arrangement of the luminophore on the surface of the anodized aluminium layer affects the time response.