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Mixed Mn-Co spinels are currently studied as protective coating materials for Solid Oxide Fuel Cells interconnects. Compositional changes in manganese cobaltites lead to modifications in the materials properties, such as sintering behaviour, thermal expansion and electrical conductivity, with advantages in the technological application. In this work, the effect of Fe, Cu and simultaneous Fe+Cu doping of Mn-Co spinels has been studied. Different oxide powder mixtures were prepared with a High Energy Ball Milling (HEBM) treatment, obtaining highly reactive oxides that easily form single spinel phase compounds by moderate heating. The effect of the composition is observed on high temperature stability of the spinel phase and on densification behaviour of the powders, greatly enhanced by copper addition. 2 Analyses carried out on sintered pellets allow to observe simple relations among dopant concentration, thermal expansion and electrical conductivity. The combined effect is obtained in case of the simultaneous addition of multiple dopants. An appropriate composition can be therefore designed to obtain a material characterized by enhanced sintering behaviour, high electrical conductivity and tailored thermal expansion to fulfil the application requirements.

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Magnetic porous metal-organic framework nanocomposite was obtained by an easy, efficient, and environmentally friendly fabrication method. The material consists in magnetic spinel iron oxide nanoparticles incorporated in an iron(III) carboxylate framework. The magnetic composite was fabricated by a multistep mechanochemical approach. In the first step, iron oxide nanoparticles were obtained via ball milling inducing mechanochemical reaction between iron chlorides and NaOH using NaCl as dispersing agent. Magnetic nanoparticles (MNs) were functionalized by neat grinding with benzene-1,3,5-tricarboxylic acid (1, 3, 5 BTC) and were then subjected to liquid assisted milling using hydrated FeCl, water, and ethanol to obtain a magnetic framework composite (MFC) consisting of iron oxide nanoparticles encapsulated in a MOF matrix. We report, for the first time, the applicability of the grinding method to obtain a magnetic composite of metal-organic frameworks. The synthesized material exhibits magnetic characteristics and high porosity, and it has been tested as carrier for targeted drug delivery studying loading and release of a model drug (doxorubicin). Developed systems can associate therapeutics and diagnostics properties with possible relevant impact for theranostic and personalized patient treatment. Furthermore, the material properties make them excellent candidates for several other applications such as catalysis, sensing, and selective sequestration processes.

Na+-conducting, binary electrolytic mixtures, based on 1-ethyl-3-methyl-imidazolium, trimethyl-butyl-ammonium, and N-alkyl-N-methyl-piperidinium ionic liquid (IL) families, were designed and investigated. The anions were selected among the per(fluoroalkylsulfonyl)imide families. Sodium bis(trifluoromethylsulfonyl)imide, NaTFSI, was selected as the salt. The NaTFSI-IL electrolytes, addressed to safer sodium battery systems, were studied and compared in terms of ionic conductivity and thermal stability as a function of the temperature, the nature of the anion and the cation aliphatic side chain length. Room temperature conductivities of interest for sodium batteries, i.e., largely overcoming 10−4 or 10−3 S cm−1, are displayed. Similar conduction values are exhibited by the EMI-based samples even below −10 °C, making these electrolyte mixtures potentially appealing also for low temperature applications. The NaTFSI-IL electrolytes, with the exception of the FSI-ones, are found to be thermally stable up to 275 °C, depending on the nature of the cation and/or anion, thus extending their applicability above 100 °C and remarkably increasing the reliability and safety of the final device, especially in the case of prolonged overheating.

Microbial lipase from Candida rugosa was immobilized by physical adsorption onto an ethylene-vinyl alcohol polymer (EVAL) functionalized with acyl chlorides. To evaluate the influence of the reagent chain-length on the amount and activity of immobilized lipase, three differently long aliphatic fatty acids were employed (C8, C12, C18), obtaining EVAL functionalization degrees ranging from 5% to 65%. The enzyme-polymer affinity increased with both the length of the alkyl chain and the matrix hydrophobicity. In particular, the esterified polymers showed a tendency to give segregated hydrophilic and hydrophobic domains. It was observed the formation of an enzyme multilayer at both low and high protein concentrations. Desorption experiments showed that Candida rugosa lipase may be adsorbed in a closed form on the polymer hydrophilic domains and in an open, active structure on the hydrophobic ones. The best results were found for the EVAL-C18 13% matrix that showed hyperactivation with both the soluble and unsoluble substrate after enzyme desorption. In addition, this supported biocatalyst retained its activity for repetitive cycles.

Physico-chemical equilibria that influence oxide powders’ precipitation from an aqueous solution can be substantially altered when the process is carried out in a microemulsion system. To obtain nanosizedMnFe2O4 and gain information about the physico- chemical characteristics of products, Mn21 and Fe31 metal ions were induced to precipitate in a toluene/water/sodium dodecylbenzenesulfonate microemulsion system. Portions of the precipitated powder were differently treated, both in solution and in the solid state, and the role of restricted aqueous domains in the obtained materials was investigated. X-ray diffraction profile-fitting methods and chemical analysis were applied to characterize the powder particles. Samples obtained from the selected microemulsion were identified as nanosized mixed hydroxide compounds. A low metal content and a limited matter exchange among aqueous nanodroplets appear to inhibit hydroxide to oxide transformation inside the selected micellar system. A calcination process of precipitated powder was required to obtain a manganese ferrite compound