We present a versatile method for the preparation of mesoporous tin-doped indium oxide (ITO) thin films via dip-coating. Two poly(isobutylene)-b-poly(ethyleneoxide) (PIB-PEO) copolymers of significantly different molecular weight (denoted as PIB-PEO 3000 and PIB-PEO 20000) are used as templates and are compared with non-templated films to clarify the effect of the template size on the crystallization and, thus, on the electrochemical properties of mesoporous ITO films. Transparent, mesoporous, conductive coatings are obtained after annealing at 500 • C; these coatings have a specific resistance of 0.5 cm at a thickness of about 100 nm. Electrical conductivity is improved by one order of magnitude by annealing under a reducing atmosphere. The two types of PIB-PEO block copolymers create mesopores with in-plane diameters of 20-25 and 35-45 nm, the latter also possessing correspondingly thicker pore walls. Impedance measurements reveal that the conductivity is significantly higher for films prepared with the template generating larger mesopores. Because of the same size of the primary nanoparticles, the enhanced conductivity is attributed to a higher conduction path cross section. Prussian blue was deposited electrochemically within the films, thus confirming the accessibility of their pores and their functionality as electrode material.

The synthesis of trans‐di(arylalkynyl)diphosphine platinum(II) complexes bearing trialkoxysilane groups is described, as well as the preparation of siloxane‐based hybrid materials from organometallic chromophores through a modified sol–gel process. Glass materials prepared from trans‐[P(n–Bu)3]2Pt[(C≡C–p–C6H4–C≡C–p–C6H4–CH2O(CO)NH(CH2)3Si(OC2H5)3]2 generally show spectral transmittance, absorption and luminescence similar to that of solutions reported in the literature. Measurements of optical power limiting for the hybrid glass are carried out, and show broadband nonlinear absorption throughout the whole visible wavelength range with clamping values in the range 0.2–7 µJ at 120 mM chromophore concentration. The sol–gel process using urethane‐propyltriethoxysilane‐functionalized chromophores as precursors appears to be a valid method for formation of robust silicate materials with grafted diarylethynyl Pt(II) complexes for OPL devices.

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International audienceThe complexing properties of a thiacalix[2]thianthrene 1 and its disulfoxide derivative 2 toward alkali metal, alkaline earth metal, some transition metal and some heavy metal cations have been investigated in acetonitrile by means of UV spectrophotometry. At the concentrations suited to this technique, complexation of the alkali metal cations by the sulfoxide but not the thiacalixthianthrene was detectable, whereas the converse was true for both transition metal and lanthanide cations. Complexation of the alkaline earth cations was not detectable. The strongest binding observed was that of Hg(II) to ligand 1 but in no case was complexation sufficiently strong for either ligand to function as a useful metal ion extractant. Graphical Abstract The complexing properties of a thiacalix[2]thianthrene 1 and its disulfoxide derivative 2 toward alkali metal, alkaline earth metal, some transition metal and some heavy metal cations have been investigated in acetonitrile by means of UV spectrophotometry. At the concentrations suited to this technique, complexation of the alkali metal cations by the sulfoxide but not the thiacalixthianthrene was detectable, whereas the converse was true for both transition metal and lanthanide cations. Complexation of the alkaline earth cations was not detectable. The strongest binding observed was that of Hg(II) to ligand 1 but in no case was complexation sufficiently strong for either ligand to function as a useful metal ion extractant

Nanoparticles of ATO (antimony doped tin oxide) were used to produce thick conductive, free standing mats of nanofibers via electrospinning. These fibrous mats were incorporated into polymer films to produce a transparent conducting polymer foil. Moreover, the fiber mats can serve as porous electrodes for electrodeposition of Prussian Blue and TiO 2 and were tested in dye-sensitized solar cells.TCO (transparent conducting oxide) materials are widely used in opto-electronic applications as transparent electrodes, commonly as thin, compact films deposited on glass or quartz substrates.1,2 These TCO layers of 200-300 nm thickness possess sheet resistances typically below 20 O/& and transparencies above 85% in the visible range, making them also suitable as two-dimensional electrodes for electrochromic devices 3 and solar cells.4 TCO films with 3D porosity with pore sizes beyond 100 nm are supposed to be useful for diverse applications. As proposed by Zaban et al., a 3D TCO electrode theoretically offers advantages for electron collection in DSSCs (dye-sensitized solar cells), 5 due to a higher surface area and a shorter electron diffusion pathway to the back electrode. The practical realization of such DSSCs with TiO 2 on ITO (indium tin oxide) nanopowders 6 and nanowires generated by laser-ablation 7 showed only low conversion efficiency, but recently a more elaborate approach based on a poly(carbonate) template yielded around 4% efficiency. 8 In addition, porous TCO electrodes might prove suitable in other applications with non-conducting polymers or oxides with low intrinsic conductivities, as for example oxide cathodes for Li-batteries. Here we demonstrate a novel procedure allowing the production of ATO (antimony doped tin oxide) nanofiber mats and their usage to endow intrinsically insulating polymer films with conductivity, and as highly porous electrodes for electrodeposition and device fabrication. To the best of our knowledge, this is the first working example of a nanofiber-based ATO electrode. For ordinary TCO electrodes, typical deposition techniques are CVD and PVD (chemical and physical vapor deposition), including spray pyrolysis, PLD (pulsed laser deposition) and magnetron sputtering, resulting in compact layers. Various attempts have been made to employ sol-gel processing, yielding good transparency, but generally much lower conductivity. Main benefits of sol-gel approaches are the possibility of solution-based coating technology and the facile generation of porosity through suitable polymer templates, as demonstrated for mesoporous and macroporous ITO.10,11 An alternative concept to endow TCOs with porosity is the generation of nanofibers by electrospinning. The combination of a suitable polymer as a carrier with conventional sol-gel processing thus can be applied for the electrospinning of metal oxide fibers, including ITO. 8,15 However, for other n-type TCO materials like ATO, FTO (fluorine doped tin oxide) or AZO (aluminum doped zinc oxide) only low conductivities have been reported, even for ...

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Optical limiting materials are developed for applications in protection of optical sensors against laser aggressions. We have studied functionalised macrocycles (thiacalixarenes) and alkynylplatinum(II) derivatives for optical limiting applications. Glass materials based on alkynylplatinum(II) derivatives and macrocycles were prepared through the solgel process. The molecular species were grafted to the matrix in order to maximise the concentration and the stability of the final solid-state material. The glass materials were cut and polished to approximately 1.5 mm. The glass materials show broadband optical limiting in the visible wavelength region, for nanosecond laser pulses.