This study presents two series of new host–guest chromophoric systems, where BODIPY dyes are organized into mesoporous silica. The dyes self‐assemble with surfactants to generate micellar templates that can direct the formation of the silica networks. The materials were characterized by means of small‐angle X‐ray scattering (SAXS) and transmission electron microscopy (TEM) to elucidate their structure, and by UV/Vis absorption spectroscopy to determine their optical properties. Dye‐loaded COK‐12 materials retain an ordered structure and exhibit a green fluorescence that slightly red‐shifts and undergoes quenching as the dye loading increases. A second system is based on MCM‐41 silica and works as a polychromatic antenna, where a high energy species forms within the template and drive excitation energy transfer in timescales down to 20 ps. Such systems show promising performances for the realization of photonic antennae, to be used as sensitizers for solar cells and photocatalytic devices.

The scientific adventure starting from simple dinuclear ruthenium(II) complexes and leading to the design, preparation, and study of photo-and redox-active polynuclear metal dendrimers capable of performing useful photo-driven processes is reviewed through decades of activity. The recent appli- [a] 3887 cations of luminescent metal dendrimers in the field of artificial photosynthesis -in particular as far as the photochemical water oxidation process is concerned -and their very recently revealed self-aggregating properties, including concentrationdependent photoinduced energy transfer, are also shown. the investigation of intercomponent photoinduced energy and electron-transfer processes. The simultaneous growth of supramolecular photochemistry [11] was indeed significantly powered by such studies, and an evolution towards larger multicomponent assembled systems appeared almost obvious. Scheme 1. Structural formulas of the polypyridine ligands mainly used for the synthesis of the metal dendrimers here described and their representations, used in the following figures.Within such a scenario, our research group started a collaboration with the groups of Vincenzo Balzani in Bologna and of Gianfranco Denti in Pisa, with the aim of building up unprecedented methods toward the synthesis of metal complexes of high nuclearity, having in mind some guidelines for preparing supramolecular assemblies capable of exhibiting made-to-order properties. In particular, photoinduced intramolecular energy transfer and predetermined redox patterns were among the properties we were looking for, since such properties were essential to open the way to artificial antenna systems for light harvesting purposes and for multiple charge storage. After the initial studies, that led us to synthesize and investigate the lumi-Microreview nescence properties and redox behavior of -among othersdinuclear, trinuclear, tetranuclear, hexanuclear, heptanuclear, Sebastiano Campagna received his Laurea in Chemistry from the University of Messina in 1983. Since 1985 to 1997 he worked in the Photochemistry group led by Vincenzo Balzani at the University of Bologna. In 1998 he joined the Faculty of Science of the University of Messina, where he became full professor in 2002. His research interests include photochemistry and photophysics of coordination compounds and supramolecular species, photoinduced electron and energy transfer, and artificial photosynthesis. Giuseppina La Ganga is post-doc student at University of Messina. She received her master degree in 2009 and received her PhD in Chemistry in 2014 from the University of Messina, working in the group of Prof. Sebastiano Campagna on supramolecular photochemistry. Her scientific interest is focused on renewable energies, with particular emphasis on the generation of solar fuels. She has developed and studied in detail various kinds of sensitizer-antenna dyes and multi-electron catalysts for water oxidation. Ambra Cancelliere obtained her Master degree in Chemistry in 2016 from the University of Messina...

The novel dendritic-shaped, heptanuclear compound 1 - the first mixed Os-Ru dendrimer with tris-chelating bridging ligands - has been synthesized and its photophysics studied by fs pump-probe transient spectroscopy. In 1, all light energy absorbed by six identical Ru(ii) chromophores is funnelled to the luminescent central Os(ii) core, with a time constant of 11 ps, by Dexter energy transfer.

The use of inorganic salt hydrates for thermochemical energy storage (TCS) applications is widely investigated. One of the drawbacks that researchers face when studying this class of materials is their tendency to undergo deliquescence phenomena. We here proposed and investigated, for the first time, the possibility of using organic salt hydrates as a paradigm for novel TCS materials with low water solubility, that is, more resistance to deliquescence, a tendency to coordinate a high number of water molecules and stability under operating conditions. The organic model compound chosen in this study was calcium; 7-[[2-(2-amino-1,3-thiazol-4-yl)-2-methoxyiminoacetyl]amino]-3-[(2-methyl-5,6-dioxo-1H-1,2,4-triazin-3-yl)sulfanylmethyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate, known as calcium ceftriaxone, hereafter named CaHS (calcium hydrated salt), a water-insoluble organic salt, which can combine up to seven water molecules. The CaHS was prepared by precipitation from the water-soluble disodium triaxone. The thermal behavior of CaHS, in terms of stability and dehydration–hydration cyclability, was assessed. The material can operate in the temperature range of 30–150 °C, suitable for TCS. No deliquescence phenomena occurred upon exposure to a relative humidity (RH) between 10 and 100%. Its heat storage capacity, so far unknown, was measured to be ~595.2 kJ/kg (or ~278.6 kWh/m3). The observed heat storage capacity, thermal stability, and good reversibility after dehydration–hydration cycles highlight the potential of this class of materials, thus opening new research paths for the development and investigation of innovative organic salt hydrates.

In this paper, tricalcium aluminate hexahydrate (Ca3Al2O6·6H2O), thanks to its appropriate features, was assessed as an innovative, low-cost and nontoxic material for thermochemical energy storage applications. The high dehydration heat and the occurring temperature (200–300 °C) suggest that this material could be more effective than conventional thermochemical storage materials operating at medium temperature. For these reasons, in the present paper, Ca3Al2O6·6H2O hydration/dehydration performances, at varying synthesis procedures, were assessed. Experimentally, a co-precipitation and a solid–solid synthesis were studied in order to develop a preparation method that better provides a performing material for this specific application field. Thermal analysis (TGA, DSC) and structural characterization (XRD) were performed to evaluate the thermochemical behavior at medium temperature of the prepared materials. Furthermore, reversibility of the dehydration process and chemical stability of the obtained materials were investigated through cycling dehydration/hydration tests. The promising results, in terms of de/hydration performance and storage density (≈200 MJ/m3), confirm the potential effectiveness of this material for thermochemical energy storage applications and encourage further developments on this topic.