Hybrid perovskite crystals with organic and inorganic structural components are able to combine desirable properties from both classes of materials. Electronic interactions between the anionic inorganic framework and functional organic cations (such as chromophores or semiconductors) can give rise to unusual photophysical properties. Cyanine dyes are a well known class of cationic organic dyes with high extinction coefficients and tunable absorption maxima all over the visible and near-infrared spectrum. Here we present the synthesis and characterization of an original 1D hybrid perovskite composed of NIR-absorbing cyanine cations and polyanionic lead halide chains. This first demonstration of a cyanine-perovskite hybrid material is paving the way to a new class of compounds with great potential for applications in photonic devices.

Tinted and colour-neutral semitransparent organic photovoltaic elements are of interest for building-integrated applications in windows, on glass roofs or on facades. We demonstrate a semitransparent organic photovoltaic cell with a dry-laminated top electrode that achieves a uniform average visible transmittance of 51% and a power conversion efficiency of 3%. The photo-active material is based on a majority blend composed of a visibly absorbing donor polymer and a fullerene acceptor, to which a selective near-infrared absorbing cyanine dye is added as a minority component. Our results show that organic ternary blends are attractive for the fabrication of semitransparent solar cells in general, because a guest component with a complementary absorption can compensate for the inevitably reduced current generation capability of a high-performing binary blend when applied as a thin, semitransparent film.

Novel, fast and reproducible way to obtain magnetic silica beads by PVA, silica and iron oxide nanoparticles cross-linking process.

Light-emitting electrochemical cells (LECs) can be fabricated as a single emissive organic/salt layer sandwiched between two electrodes, offering cost-effective next generation signage and lighting applications. Cyanine dyes are especially attractive to exploit the low cost potential of LECs. Cyanines denote a large class of fluorescent organic salts with tuneable emission wavelength, inherent conductivity for ionic and electronic charges, and many cyanines are commercially available at low cost. We systematically tested a set of cyanine dyes for visible emitting LECs. To circumvent non-radiative quenching processes in pure cyanine films (monomer fluorescence quantum yields, PLQE, < 1.5%) we exploited the efficient resonance energy transfer (RET) from cyanine host to cyanine guest molecules (PLQE maximum = 16.2%). The analysis indicated that specific host-guest interactions or a parallel energy transfer channel to host dimers can reduce the guest PLQE, despite a generally high RET efficiency in cyanine host-guest systems. By comparing single component with host-guest LECs, we found that the PLQE enhancement directly translated into the device efficiency increase, and red-emitting host-guest LECs with an external quantum efficiency (EQE) of 0.36% were achieved, close to the theoretical EQE maximum (0.81%). Chemical approaches that provide sterically demanding (to increase the PLQE) and high bandgap (for emission at smaller wavelengths) cyanines at low cost promise further progress in the field.