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A novel 3 wt.% Fe-containing clinoptilolite catalyst was prepared starting from a natural zeolite followed by a ion-exchange synthesis. A Fe-containing ZSM-5 catalyst (commercial zeolite as support) was also prepared for comparison purpose. Both Fe-based catalysts, along with the unexchanged samples, were characterized by complementary techniques (e.g. X-ray powder diffraction (XRD), N2physisorption at –196°C, transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectrometry (EDS) microanalysis). Then, their possible application in wastewater remediation was tested with a solution of azo-dyes acid orange 7 (AO7), as target molecule for azo dyes. As a whole, remarkable results in the AO7 degradation were obtained with the Fe-clinoptilolite in the presence of both ascorbic acid (AA) and H2O2. Specifically, AO7 conversion of about 60% was observed over the Fe-clinoptilolite (reaction time = 60 min). Lower performances were achieved in the presence of Fe-ZSM-5 coupled with ascorbic acid and H2O2(AO7 conversion ~ 40%, t = 60 min.), despite the significantly higher SSA of the commercial ZSM-5. Noteworthy, the beneficial role of the ascorbic acid coupled with H2O2was observed for both Fe-containing catalysts, thus confirming the key role of both oxidant and reductant agents in Fenton-like processes.

Solid Oxide Cell electrode engineering is of paramount importance to obtain high performing, versatile and reliable devices. In this work, the structural and morphological evolution of Sr2FeNi0.4Mo0.6O6-δ(SFNM) is investigated and fully characterized over subsequent temperature programmed reductions. Comparison of the results of X-ray diffraction, high transmission electron microscopy and electrochemical impedance spectroscopy analyses confirms how metallic phase exsolution upon reduction endows the perovskite with highly active Ni-Fe-based catalytic sites for applications in hydrogen-fueled SOFCs. As a novelty, this study presents voltage-induced reduction of SFNM at 1.6 V as a fast and reliable way to induce morphological and structural changes of the SFMN-derivate exsolved-perovskite. This enhances its catalytic activity towards CO2electrolysis in SOEC configuration, providing SFNM with a high versatility in solid oxide cells applications.