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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.

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.