Solid Oxide Fuel Cells (SOFCs) are electrochemical devices capable of converting and storing energy in a sustainable and efficient way. The decrease of the operating temperature could be of great help for their diffusion. The use of nanocomposites is a smooth way to design materials with many advanced functionalities that could not be reached at the same time with only a single component. Our aim is in developing LSGF-based nanocomposites by depositing oxides' nanoparticles in order to improve the electrocatalytic performances. In this first part we focussed on cathode and iron oxide was deposited by wet impregnation. The composites' powders have been extensively characterized by means of XRD, XPS, N 2-asdorption, SEM, EDX, TPR, O 2-TPD and the results compared with those obtained for LSGF. The supporting perovskite stabilizes Fe(II) and a deep interaction between the deposited oxides and the perovskite surface is evident. Fe was observed to diffuse inside the perovskite during thermal treatments and this phenomenon greatly affects oxygen vacancies, mobility, and exchange capability. Focusing on the IT-SOFCs, symmetric cells of the type FeO x +LSGF/CGO/LSGF+FeO x have been prepared starting from the nanocomposites' powder. The effect of the SOFCs preparation conditions (temperature, atmosphere) on the electrode and on the cell has been assessed and compared, also through in-situ high temperature XRD, simulating, on the electrodes' powder, the same treatment necessary to prepare the cell. The use of nanocomposites powders as starting point for electrodes allows to deeply modify the electrochemical performance. A thin, Sr/Fe-rich foil forms on the surface of the electrode during SOFC thermal treatment and deeply improves the electrochemical behaviour of the FeO x +LSGF cathode. The electrochemical results are encouraging for future application in SOFCs, as nanocomposite has an ASR of 2.1 Ω•cm 2 at 620°C, only ⅓ of LSGF's one in the same conditions.

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Cu-based cermets suitable for electrodes in Symmetric and Reversible Solid Oxide Fuel Cells (SR-SOFCs) based on the Cerium Gadolinum Oxide (CGO) electrolyte were developed and successfully tested in the intermediate temperature range (600-800°C). The Cu/CGO cermets were prepared by means of a self-combustion based citrate procedure and the effects of synthesis conditions were studied. Characterization of the Cu/CGO nanocomposites by XPS, XRD, SEM, TPR suggested that this procedure allows obtaining highly dispersed CuO on the cerium gadolinium oxide. Conversion higher than 80% was observed above 600°C in methane total oxidation. Synthesis parameters affected both properties and catalytic performance. The behaviour under redox conditions was studied by operando high-energy XRD under oscillating H 2 /O 2 feed. Reducing conditions converted CuO into Cu(0) passing through an intermediate Cu 2 O phase while increasing the conductivity and the reactivity. This structural modification was completely reversible. The high stability, reversibility, catalytic activity and electrochemical performance make these electrodes promising for SR-SOFCs.

In this contribution, a reversible Solid Oxide Cell based on perovskites was developed. La0.6Sr0.4Ga0.3Fe0.7O3 (LSGF) was chosen as electrode and deposited onto La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM) electrolyte. The cell was investigated from the morphological (SEM) and compatibility (XRD) point of view. Electrochemical investigation confirmed that the cell can operate in fuel cell and in electrolyser modes. Impregnation with CGO and Pd allowed a 15 times increment of the power density (until limit is the cell architecture). The same cell with an impregnated negative electrode was then tested in steam electrolysis mode in a non-reducing environment. The overall performance is slightly lower than state-of-the-art materials and comparable with similar perovskites, and in general is fair considering the needed cell optimisation (i.e a anode supported configuration is necessary). The cell (impregnated and not) activates at 0.7 V. Obtained data suggest thus LSGF/LSGM/LSGF cell, is promising as reversible SOC for intermediate temperature.

The development of protective and safe textiles is of fundamental\ud importance for defending the human body from bacterial infections. To this aim,\ud garments are often functionalized with antibacterial agents. We recently started a\ud program aimed at covalently linking antimicrobial peptides to cotton tissues. To\ud optimize the process of binding, it is necessary to know the degree of functionalization\ud and how deeply peptides penetrate into the cotton fiber. Here, we present a\ud spin-label electron paramagnetic resonance (EPR) approach for obtaining data on\ud the peptide incorporation into the fibers. The approach is based on the line broadening\ud in conventional EPR and on the signal decays in electron spin echo spectroscopy\ud that is a pulsed version of EPR