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Copper and silver nanowires have been extensively investigated as the next generation of transparent conductive electrodes (TCEs) due to their ability to form percolating networks. Recently, they have been exploited as electrocatalysts for CO 2 reduction. In this review, we present the most recent advances in this field summarizing different strategies used for the synthesis and functionalization/activation of copper and silver nanowires, as well as, the state of the art of their electrochemical performance with particular emphasis on the effect of the nanowire morphology. Novel perspectives for the development of highly efficient, selective, and stable electrocatalysts for CO 2 reduction arise from the translation of NW-based TCEs in this challenging field.

We report the identification and quantitative isolation of Au 145 (SR) 60 X (R = n -butyl, n -pentyl; X = halide) along with elucidation of key properties as compared to the corresponding ubiquitous chiral-icosahedral Au 144 (SR) 60 cluster known to have a central vacancy. The stoichiometries were assessed by electrospray mass spectrometry (ESI-MS) at isotopic resolution, and induced dissociation patterns indicate the 'extra' (Au,Br) atoms are strongly bound components of these structures. Voltammetric and spectroscopic characterization reveals Au 145 (SR) 60 X behaviors that are qualitatively similar to yet fascinatingly distinct from those of Au 144 (SR) 60 . ( 1 H, 13 C)-NMR spectra clearly show how both Au 145 (SR) 60 X and Au 144 (SR) 60 are capped by 12 distinct ligand types of 5-fold equivalence, as was recently established for Au 144 (SR) 60 capped by shorter ligands, demonstrating that this novel cluster shares the same chiral-icosahedral motif. Intriguingly, Au 145 (SR) 60 X is strongly near-IR luminescent, whereas under comparable conditions Au 144 (SR) 60 barely emits. The photoluminescence pattern of Au 145 (SR) 60 X is very similar to that observed for Au 25 (SR) 18 , which contains the Au 13 core. The combined results are interpreted as consistent with neutral Au 145 (SR) 60 X as a diamagnetic species, electronically and structurally similar to the corresponding Au 144 (SR) 60 compounds.

The generation, under self-assembly conditions, of coordination polymers on surface based combinations of a terpyridine-antracene-pyridine based tecton and Co(II) or Pd(II) cations is primarily governed by the coordination geometry of the metal center (octahedral and square planar respectively). While the octahedral Co(II) based polymer self-assembles in insulating films exhibiting randomly oriented crystalline domains, the planarity of Pd(II) based polymers leads to the formation of conductive π-π stacked fibrillar structures exhibiting anisotropically oriented domains. In the latter case, the favorable Pd-Pd and anthracene-anthracene wavefunction overlaps along the fiber direction are responsible for the large electronic couplings between adjacent chains, whereas small electronic couplings are instead found along individual polymer chains. These results provide important guidelines for the design of conductive metal coordination polymers, highlighting the fundamental role of both intra- as well as inter-chain interactions, thus opening up new perspectives towards their application in functional devices.

Fast and efficient energy transfer among dyes confined in nanocontainers provides the basis of outstanding functionalities in new-generation luminescent probes. This feature article provides an overview of recent research achievements on luminescent Pluronic-Silica NanoParticles (PluS NPs), a class of extremely monodisperse core-shell nanoparticles whose design can be easily tuned to match specific needs for diverse applications based on luminescence, and that have already been successfully tested in in vivo imaging. An outline of their outstanding properties, such as tuneability, bright and photoswitchable fluorescence and electrochemiluminescence, will be supported by a critical discussion of our recent works in this field. Furthermore, novel data and simulations will be presented to (i) thoroughly examine common issues arising from the inclusion of multiple dyes in a small silica core, and (ii) show the emergence of a cooperative behaviour among embedded dyes. Such cooperative behaviour provides a handle for fine control of brightness, emission colour and self-quenching phenomena in PluS NPs, leading to significantly enhanced signal to noise ratios.

Biocompatible highly bright silica nanoparticles were designed, prepared and tested in small living organisms for both in vivo and ex vivo imaging. The results that we report here demonstrate that they are suitable for optical imaging applications as a possible alternative to commercially available fluorescent materials including quantum dots. Moreover, the tunability of their photophysical properties, which was enhanced by the use of different dyes as doping agents, constitutes a very important added value in the field of medical diagnostics., (This journal is © The Royal Society of Chemistry 2012)