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Lithium metal batteries (LMBs) will be a breakthrough in automotive applications, but they require the development of next-generation solid-state electrolytes (SSEs) to stabilize the anode interface. Polymer-in-ceramic PEO/TiO

A series of isomorphous mononuclear complexes of Ln(III) ions comprising one stable tripoidal oxazolidine nitroxyl radical were obtained in acetonitrile media starting from nitrates. The compounds, [LnRad(NO3)3] (Ln = Gd, Tb, Dy, Tm, Y; Rad = 4,4-dimethyl-2,2-bis(pyridin-2-yl)-1,3-oxazolidine-3-oxyl), have molecular structure. Their coordination polyhedron, LnO7N2, can be described as a tricapped trigonal prism with symmetry close to D3h. The value of 23 cm-1 for the antiferromagnetic coupling Gd-Rad established from the DC magnetic and EPR data is a record strength for the complexes of 4f-elements with nitroxyl radicals. The terbium derivative displays frequency-dependent out-of-phase signals in zero field indicating single-molecule magnetic behavior with an effective barrier of 57 cm-1.

The role of thiourea as an organic additive in the nucleation and growth mechanism was studied for copper deposition and its application in the decorative electroplating and fashion accessory industries. The bath was designed to reduce the environmental and ecological impacts using methanesulfonic acid as electrolyte as an alternative to alkaline cyanide baths. We evaluated the nucleation and growth mechanism of copper exploiting voltametric and chronoamperometric measurements with a brightener concentration ranging from 0 to 90 ppm. We used the Scharifker–Hills model to estimate the type of nucleation mechanism after progressive addition of thiourea. Scanning electron microscope was employed for surface analysis and morphological characterisation of the nuclei. We verified that progressive nucleation is a key step in the obtainment of a shiny and homogeneous copper film, but an excess of thiourea could cause parasitic adsorption reactions on the surface of the substrate. X-ray fluorescence spectroscopy was used for the thickness determination of the copper deposits and the electrodeposition efficiency correlated to thiourea concentration. Finally, the optimal concentration of thiourea was assessed to be 60 ppm for the used formulation of copper plating.

Superconductors and magnetic materials, including molecules, are key ingredients for quantum and advanced spintronic applications. However, only a little is known about how these materials are mutually influenced at their interface in hybrid architectures. Here, we show that a single layer of magnetic molecules, the Terbium(III) bis-phthalocyaninato (TbPc2) complexes, deposited on a superconducting Pb(111) surface is sensitive to the topology of the intermediate state of the superconductor, namely to the presence and evolution of superconducting and normal domains due to the magnetic field screening and penetration. The evidence of this sensitivity is found in the magnetisation dynamics of the TbPc2 sub-monolayer in its paramagnetic regime showing the fingerprint of the topological hysteresis of the superconducting substrate. This study reveals the great potentialities hold by thin layers of magnetic molecules for sensing local magnetic field variation in hybrid molecular/superconductor architectures, including spin resonators or spin injection devices for spintronics applications.

Lithium metal batteries (LMBs) will be a breakthrough in automotive applications, but they require the development of next-generation solid-state electrolytes (SSEs) to stabilize the anode interface. Polymer-in-ceramic PEO/TiO2 nanocomposite SSEs show outstanding properties, allowing unprecedented LMBs durability and self-healing capabilities. However, the mechanism underlying the inhibition/delay of dendrite growth is not well understood. In fact, the inorganic phase could act as both a chemical and a mechanical barrier to dendrite propagation. Combining advanced in situ and ex situ experimental techniques, we demonstrate that oligo(ethylene oxide)-capped TiO2, although chemically inert toward lithium metal, imparts SSE with mechanical and dynamical properties particularly favorable for application. The self-healing characteristics are due to the interplay between mechanical robustness and high local polymer mobility which promotes the disruption of the electric continuity of the lithium dendrites (razor effect).

In the field of the renewables, a large effort has been devoted in the last years to obtain conventional and new materials for solar energy conversion by using methods which couple a good efficiency and scalability with energetic and environmental concerns. This research has included the so-called kesterites, materials considered interesting for the thin-film solar cell technology, consisting of relatively abundant and harmless elements: Cu3-x-yFexZnySn(S,Se)(4). In this study, we undertook the synthesis of members of the kuramite-stannite (Cu3SnS4-Cu2FeSnS4) join by means of a two-step solvothermal approach, able to provide nanocrystalline products in an easy, low-temperature, and fast way. The sample with the highest Fe concentration was characterised by means of a multi-analytical approach, aimed to assess not only its final structural, chemical and micromorphological features, but also the redox speciation of the two transition metal cations, i.e. Cu and Fe, in relation to the overall charge balance. Namely, Electron Paramagnetic Resonance (EPR), Mossbauer and X-ray Absorption Spectroscopy (XAS) and SQUID magnetometry were involved. The main results point out an excellent control of the structural features, and an intermediate Fe content in the sample, leading to the following formula unit: Cu2.2Fe0.48Sn1.2S4. The overall findings of the multi-analytical characterization imply a complex redox balance, where inferring the site occupancy is not trivial; the charge balance, in fact, can only be achieved taking into account the presence of both Fe(III) and vacancies. Moreover, Fe is distributed over two different crystallographic sites.

Three transition metal heptanuclear clusters, [Co7L6(μ3-OCH3)6](ClO4)2·H2O (1), [Ni7L6(μ3-OH)6](ClO4)2·4DMF (2), [Zn7L6(μ3-OCH3)6](ClO4)2 (3), have been obtained using a new Schiff base ligand (HL) derived from o-vanillin and 2-methoxybenzylamine. The structures of 1–3 have been determined based on single crystal X-ray diffraction studies. They have similar wheel structures in which six metal ions locate on the rim with the seventh metal ion in the center. Complex 3 exhibits luminescence in the solid state at room temperature. Variable-temperature DC and AC magnetic studies were carried out on polycrystalline samples of 1 and 2. Compound 1 shows an overall ferromagnetic coupling and absence of SMM behavior despite the observation of out-of-phase susceptibility in external applied field. The analysis of the magnetic data for compound 2 emphasizes the interplay of ferromagnetic interactions between central and peripheral nickel(II) ions (J1 = −11.2 cm−1), and antiferromagnetic interactions between the peripheral nickel(II) ions (J2 = 9.6 cm−1); H = ΣJijSiSj.

The possibility to operate on magnetic materials through the application of electric rather than magnetic fields—promising faster, more compact and energy efficient circuits—continues to spur the investigation of magnetoelectric effects. Symmetry considerations, in particular the lack of an inversion centre, characterize the magnetoelectric effect. In addition, spin–orbit coupling is generally considered necessary to make a spin system sensitive to a charge distribution. However, a magnetoelectric effect not relying on spin–orbit coupling is appealing for spin-based quantum technologies. Here, we report the detection of a magnetoelectric effect that we attribute to an electric field modulation of the magnetic exchange interaction without atomic displacement. The effect is visible in electron paramagnetic resonance absorption of molecular helices under electric field modulation and confirmed by specific symmetry properties and spectral simulation. A modulation of the magnetic exchange interaction using an electric field, in the absence of atomic displacement and not relying on spin–orbit coupling, is reported.

Quaternary semiconducting sulphides are promising and sustainable candidates to replace the silicon-based semiconducting materials currently leading the market of the photovoltaic energy production. Recent efforts were paid to CZTS (Copper Zinc Tin Sulphides) semiconductors, due to their suitable electronic properties, the abundance in nature of their constituents, and the low toxicity. In this study, we synthetized Cu3-xZnxSnS4 samples by two different solvothermal approaches, with the aim of developing a sustainable synthetic route in the cradle-to-grave full life cycle assessment. These two routes are characterized by either a single step, or a two-steps procedure and allow operating in mild conditions limiting the use of additional chemicals. A multi-technique characterization protocol has been adopted to evaluate chemical, structural and functional properties of the final products. The selected analyses demonstrated that, in both cases, members of the kesterite-kuramite solid solution series were obtained. Still, only in the case of the two steps approach pure Cu2ZnSnS4 samples can be synthesized, whereas the single step synthesis yields Zn-poor samples. The optical characterization of the optimized CZTS material obtained with the two-steps approach revealed a band gap value (1.6 eV), in line with literature's values, confirming the suitability of this synthesis for the development of materials for photovoltaic applications.

Although technological and processing advancements occurred in the past forty years, industrial firms are still struggling to provide solutions to corrosion protection as well as reduction of toxic wastes. Specifically, large-scale industrialization of electroplating techniques will continue to be limited by strict environmental regulations. Moreover, price volatility of the highly demanding electroplated materials like gold, palladium, copper and nickel will heavily impact the market in the next years. In that respect, alloy plating offers better answers in terms of economic growth and environmental sustainability due to fine tuning composition, morphology and crystallinity [1]. The main categories of alloy compounds are presented and the most important properties for the manufacturing process discussed. Particular attention is devoted to advances in industrial quality control and viable solutions for the reduction of precious metal content in electroplated accessories as well as replacement of cyanide and nickel baths with non-toxic compounds, also considering the commercial needs of wear resistance and aesthetic characteristics of gloss. The electrodeposition of Cu-Sn alloys (bronze) has earned considerable interest thanks to the chemical-physical properties of this alloy, which make it a valid substitute for nickel in fashion industry. Generally, most of the bronze coatings are electroplated starting from baths containing cyanides, and the metal precursors are selected as cyanide compounds. Free cyanide is a well-known problem in the galvanic production cycle both in terms of toxicity for the workers as well as for the environment, and in terms of costs associated with its disposal. The aim of this study is to develop an electroplating bath totally cyanide-free, therefore formulated in an innovative way and which, in addition to being free from this dangerous species, has an eco-friendly support electrolyte. To achieve this goal, methanesulfonic acid (MSA) was chosen as electrolyte, which is biodegradable as part of the natural sulfur cycle. We've studied different formulations in terms of metal precursors, organic additives and their concentrations [2-3]. The same cyanide issue is present also in for the electrodeposition of silver, for this reason the influence of polyethyleneimine (PEI) as additive for cyanide-free silver bath, in combination with 5,5-dimethylhydantoin (DMH) as complexing agent, was studied [4]. Chronoamperometry was used to investigate the electrodeposition mechanism, which is found to be a three-dimensional diffusion-controlled nucleation and growth mechanism, according to the Scharifker–Mostany’s model. Smoother, brighter and blue colored silver deposits are obtained in the presence of PEI in a Hull’s cell test, at low density current. Eventually, the influence of nitrate anion is also investigated. The presence of nitrate increases the range of current density allowing for an effective Ag deposition. We also investigated the use of modulated currents to increase the throwing power of electroplating, obtaining a more uniform deposition and reducing the amount of metals but maintaining the required characteristics. Pulsed current justifies its practical application mainly through its ability to influence the mechanisms of electrocrystallisation, which in turn control the mechanical and physical properties of the deposited metal. By simply adjusting the amplitude and length of the pulses, it is possible to control not only the composition and thickness, in atomic order, of the deposits, but to improve their characteristics such as grain size, porosity and homogeneity [5]. The authors acknowledge Regione Toscana POR CreO FESR 2014-2020 – azione 1.1.5 sub-azione a1 – Bando 1 “Progetti Strategici di ricerca e sviluppo” which made possible the projects “A.C.A.L. 4.0” (CUP 3553.04032020.158000165_1385), “A.M.P.E.R.E.” (CUP 3553.04032020.158000223_1538) and “GoodGalv” (3647.04032020.157000060). References [1] Giurlani, W.; Zangari, G.; Gambinossi, F.; Passaponti, M.; Salvietti, E.; Di Benedetto, F.; Caporali, S.; Innocenti, M. Electroplating for Decorative Applications: Recent Trends in Research and Development. Coatings 2018, 8, 260, doi:10.3390/coatings8080260. [2] Fabbri, L.; Sun, Y.; Piciollo, E.; Salvietti, E.; Zangari, G.; Passaponti, M.; Innocenti, M. Electrodeposition of White Bronzes on the Way to CZTS Absorber Films. J. Electrochem. Soc. 2020 , 167, 022513, doi: 10.1149/1945-7111/ab6c59. [3] Fabbri, L.; Giurlani, W.; Mencherini, G.; De Luca, A.; Passaponti, M.; Piciollo, E.; Fontanesi, C.; Caneschi, A.; Innocenti, M. Optimisation of Thiourea Concentration in a Decorative Copper Plating Acid Bath Based on Methanesulfonic Electrolyte. Coatings 2022, 12, 376, doi:10.3390/coatings12030376. [4] Pizzetti, F.; Salvietti, E.; Giurlani, W.; Emanuele, R.; Fontanesi, C.; Innocenti, M. Cyanide-free silver electrodeposition with polyethyleneimine and 5,5-dimethylhydantoin as organic additives for an environmentally friendly formulation. J. Electroanal. Chem. 2022, 911, 116196, doi:10.1016/j.jelechem.2022.116196. [5] Popov, K.I.; Nikolić, N.D. General Theory of Disperse Metal Electrodeposits Formation. In; Djokić, S.S., Ed.; Modern Aspects of Electrochemistry; Springer US: Boston, MA, 2012; Vol. 54, pp. 1–62 ISBN 978-1-4614-2379-9.

The Sustainable Development Goals (SDGs) have been proposed to give a possible future to humankind. Due to the multidimensional characteristic of sustainability, SDGs need research activities with a multidisciplinary approach. This work aims to provide a critical review of the results concerning sustainable materials obtained by Italian researchers affiliated to the National Interuniversity Consortium of Materials Science and Technology (INSTM) and their contribution to reaching specific indicators of the 17 SDGs. Data were exposed by using the Web of Science (WoS) database. In the investigated period (from 2016 to 2020), 333 works about sustainable materials are found and grouped in one of the following categories: chemicals (33%), composites (11%), novel materials for pollutants sequestration (8%), bio-based and food-based materials (10%), materials for green building (8%), and materials for energy (29%). This review contributes to increasing the awareness of several of the issues concerning sustainable materials but also to encouraging the researchers to focus on SDGs’ interconnections. Indeed, the mapping of the achievements can be relevant to the decision-makers to identify the opportunities that materials can offer to achieve the final goals. In this frame, a “Sustainable Materials Partnership for SDGs” is envisaged for more suitable resource management in the future.

The structure and growth mechanism of TiO2 ultrathin films on Cu(001) were investigated by experimental and theoretical studies. Multiple experimental techniques, including photoemission spectroscopies and scanning probe microscopy, were used to carefully characterize the chemical, electronic, and morphological structure of the metal oxide layer. A complete and flat TiO2 bilayer with a lepidocrocite-like structure is observed at the earliest stages of its growth on the Cu(001) surface under controlled experimental conditions. The employed multitechnique approach reveals that a transition between two different structures of the TiO2 film, that is, the quasi-hexagonal and lepidocrocite-like structure, occurs as a function of the coverage passing from one to two monolayers. Ab initio calculations indicate that the lepidocrocite-like structure is thermodynamically more stable on Cu(001) than the quasi-hexagonal one, thus supporting the observed transition.

Cross-fertilization between molecular magnetism and organic spintronics is leading to the development of concepts based on the use of molecules as active elements to influence spin-related transport processes. The research on hybrid devices, where the magnetic molecules in contact with the electrodes influence the spin and charge injection and transport, is moving its first steps but is expected to quickly expand the technological potential of molecular spintronics and quantum computing. New exciting possibilities, linked to the individual properties of these molecular units and to their interaction with novel substrates, are getting disclosed. The chemical functionalization of these molecules is the tool which allows to tune their electronic and magnetic properties and to directly create these hybrid architectures. However, the coupling of molecules with the spin transport phenomena is far from being trivial. First, the stability of molecules in the device environment must be tested and, subsequently, the organization of molecules in the desired architectures must be mastered permitting a careful control of the interactions between inorganic substrates and molecular layers. Here we summarize how this research activity can be developed in the case of one of the simplest magnetic molecules, an organic radical. We will start from an innocent surface, such as gold, to move then toward a real-device environment. We evidence how these efforts can result in a surface-specific molecular-based method to influence the spin injection and transport phenomena, paving the way for developing new devices in which a fine-tuning of magnetic features is required.

The search for new environment-friendly visible-light absorbing catalysts is an urgent task. g-C3N4 has excellent photocatalytic properties and the possibility of developing cost-effective routes to make this material a viable alternative to the currently used catalysts is required. In this work, we show that a simple chemical oxidation process of g-C3N4 with nitric acid allowed significantly enhancing the hydrogen photogeneration from aqueous triethanolamine, under simulated solar light. An 8-fold improvement of the H2 production, with respect to the pristine sample, was achieved by properly controlling the physical-chemical parameters of the oxidation process, reaching a value of about 4000 μmol g-1 h-1, which is one of the highest hydrogen production rates for bulk g-C3N4. Such high levels of photocatalytic activity result from the combination of improved surface area and changes in the electronic structure induced by the oxidation process.

The reactions of cobalt(II) perchlorate with a diazine tetratopic helicand, H4L, in the presence of sodium carbonate afford two coordination polymers constructed from tetranuclear anionic helicates as building blocks: ∞3[Co4L3Na4(H2O)4]·4H2O (1) and ∞2[Co5L3Na2(H2O)9]·2.7H2O·DMF (2). The tetranuclear triple-stranded helicates, {CoII4L3}4–, are connected in 1 by sodium(I) ions and in 2 by sodium(I) and cobalt(II) ions (H4L results from the condensation reaction between 3-formylsalicylic acid and hydrazine). The crystal structures of the two compounds have been solved. In both compounds the anionic helicates interact with the assembling cations through the carboxylato oxygen atoms. Compound 2 features chains resulting from connecting the tetranuclear helicates through cobalt(II) ions. The analysis of the magnetic properties of compounds 1 and 2 evidenced a dominant antiferromagnetic coupling for 1, resulting in a diamagnetic ground state. In contrast, the magnetic behavior of 2 is dominated at low temperatu...

The magnetic properties of some single molecule magnets (SMM) on surfaces can be strongly modified by the molecular packing in nanometric films/aggregates or by interactions with the substrate, which affect the molecular orientation and geometry. Detailed investigations of the magnetism of thin SMM films and nanostructures are necessary for the development of spin-based molecular devices, however this task is challenged by the limited sensitivity of laboratory-based magnetometric techniques and often requires access to synchrotron light sources to perform surface sensitive X-ray magnetic circular dichroism (XMCD) investigations. Here we show that low-temperature magnetic force microscopy is an alternative powerful laboratory tool able to extract the field dependence of the magnetization and to identify areas of in-plane and perpendicular magnetic anisotropy in microarrays of the SMM terbium(III) bis-phthalocyaninato (TbPc2) neutral complex grown as nanosized films on SiO2 and perylene-3,4,9,10-tetracarbox...

Magnetic crystals formed by 2D layers interacting by weak van der Waals forces are currently a hot research topic. When these crystals are thinned to nanometric size, they can manifest strikingly different magnetic behavior compared to the bulk form. This can be the result of, for example, quantum electronic confinement effects, the presence of defects, or pinning of the crystallographic structure in metastable phases induced by the exfoliation process. In this work, an investigation of the magnetism of micromechanically cleaved CrCl

Magnetochiral dichroism (MChD) is a nonreciprocal manifestation of light-matter interaction that can be observed in chiral magnetized systems. It features a differential absorption of unpolarized light depending on the relative orientation of the magnetic field and the light wavevector and on the absolute configuration of the system. The relevance of this effect for optical readout of magnetic data calls for a complete understanding of the microscopic parameters driving MChD with an easy-accessible and nondamaging light source, such as visible light. For this purpose, here we report on MChD detected with visible light on a chiral magnetic helix formulated as [MnIII(cyclam)(SO4)]ClO4·H2O (cyclam = 1,4,8,11-tetraazacyclotetradecane) featuring antiferromagnetically coupled anisotropic MnIII ions. Alternate current susceptibility measurements revealed the existence of a single-chain magnet behavior hidden below the canted antiferromagnetism (TN = 5.8 K) already evidenced by direct current magnetometry. A detailed analysis of the optical absorption gives access to the value of the zero-field splitting parameter D (2.9 cm-1), which quantifies the magnetic anisotropy of the MnIII centers. Below the magnetic ordering temperature of the material, the MChD spectra exhibit intense absolute configuration dependent MChD signals reaching record values of ca. 12% of the absorbed intensity for the two electronic transitions most influenced by the spin-orbit coupling of the MnIII ion. These findings set a clear route toward the design and preparation of highly MChD-responsive molecular materials.

Magnetic crystals formed by 2D layers interacting by weak van der Waals forces are currently a hot research topic. When these crystals are thinned to nanometric size, they can manifest strikingly different magnetic behavior compared to the bulk form. This can be the result of, for example, quantum electronic confinement effects, the presence of defects, or pinning of the crystallographic structure in metastable phases induced by the exfoliation process. In this work, an investigation of the magnetism of micromechanically cleaved CrCl3 flakes with thickness >10 nm is performed. These flakes are characterized by superconducting quantum interference device magnetometry, surface-sensitive X-ray magnetic circular dichroism, and spatially resolved magnetic force microscopy. The results highlight an enhancement of the CrCl3 antiferromagnetic interlayer interaction that appears to be independent of the flake size when the thickness is tens of nanometers. The estimated exchange field is 9 kOe, representing an increase of ≈900% compared to the one of the bulk crystals. This effect can be attributed to the pinning of the high-temperature monoclinic structure, as recently suggested by polarized Raman spectroscopy investigations in thin (8-35 nm) CrCl3 flakes.

The terbium(III) ion is a particularly suitable candidate for the creation of surface-based magnetic and luminescent devices. In the present work, we report the epitaxial growth of needle-like objects composed of [Tb(hfac)3·2H2O]n (where hfac = hexafluoroacetylacetonate) polymeric units on muscovite mica, which is observed by atomic force microscopy. The needle-like shape mimics the structure observed in the crystalline bulk material. The growth of this molecular organization is assisted by water adsorption on the freshly air-cleaved muscovite mica. This deposition technique allows for the observation of a significant amount of nanochains grown along three preferential directions 60° apart from another. The magnetic properties and the luminescence of the nanochains can be detected without the need of surface-dedicated instrumentation. The intermediate value of the observed luminescence lifetime of the deposits (132 µs) compared to that of the bulk (375 µs) and the CHCl3 solution (13 µs) further reinforces the idea of water-induced growth.

International audience; This work describes the study of molecular junctions embedding the spin crossover complex [Fe(H2B(pz)2)2(phen)] as an active switchable thin film. In these junctions we observed that the spin state conversion causes a gradual increase in the current density, which may be due to a crossover from direct tunneling to multi-step hopping.

his work is aimed at finding optimal formulations of silver nanowires (AgNWs) and graphene derivatives, including proper assembly and engineering in 2D hybrid substrates, to define a standard, simple and reproducible procedure for surface-enhanced Raman spectroscopy (SERS) detection of proteins. AgNWs (5±3 ?m in length, 48±10 nm in diameter) were synthesized by the chemical reduction method of silver nitrate (AgNO3) in ethylene glycole (EG) and polyvinylpirrolidone (PVP), according to Hu et al.[1] with few changes. The reaction has been optimized in order to obtain a good yield of nanowires and good reproducibility. AgNWs were characterized by Scanning electron microscope (SEM) and UV-Vis spectroscopy. The synthesized AgNWs were assembled to obtain a 2D array to provide a random homogeneous distribution. Aerosol deposition was selected as simple and very low-cost method to fabbricate dot array AgNWs SERS substrates. In this study hybrid nanocomposite, obtained by the depositon of AgNWs on graphene nanoplatlets-based paper (G-PAPER), were compared with an array of AgNWs on Polytetrafluoroethylene (PTFE) membrane[2], according the same deposition condition. The as-fabricated substrates were first characterized by atomic force microscopy (AFM), and secondly were analyzed under a microRaman spectrometer to test their optical response. Finally, selected substrates were used for direct detection of myoglobin as reference protein, upon simple deposition of few-microliter drops of solution on the top of the substrate followed by evaporation and Raman inspection. The as-obtained spectra showed comparable SERS profile. Furthermore, we observed a substantial improvement in signal-to-noise ratio with quenching of fluorescence background in the hybrid SERS substrate.

This work is focused on the realization of a new manufacturing process based on the introduction of TiO2 nanostructured coatings on the surface of red earthenware pottery for domestic use. The aim of the study is to improve the technical properties of the product made from lime and iron-rich clays used to produce traditional artistic Tuscan pottery (Italy). The identified strategy involves the application of nanoparticles onto the surface of ceramic substrates via a sol-gel based process; the initial porosity of the Earthenware promotes the insertion of inert nanoparticles in the outermost part of the ceramic material by simple immersion of bisqueware in the colloidal solutions of nanoparticles. Morphological investigation of the functionalized surfaces has been carried out by scanning electron microscope and atomic force microscopy, while the effectiveness of the treatment was checked by evaluating the water absorption capacity in compliance with the standard method AS-1012.21-1999. The obtained results show a reduction of surface porosity, which turns into a reduced water uptake respect to the traditional pottery, maintaining, at the same time, identical aesthetical characteristics.

We present multifunctional, biocompatible and biodegradable magnetic nanovectors based on different polyamidoamine (PAA) polymers tailored with different diagnostic and therapeutic properties. Using maghemite nanoparticles with average size 15.5 +/- 2.8 rim prepared by thermal decomposition, superparamagnetic nanovectors were obtained by coating the nanoparticles with synthetic polymers of PM. These have a segmented copolymer structure, and bear PAA segments containing different amount of carboxyl groups per repeating units together with PEG segments. These copolymers are thought to combine the binding properties of the carboxylated PM segments to inorganic nanoparticles, with the stealth properties of the PEG ones. The magnetic, hyperthermal and relaxometric properties of the synthesized samples were investigated. Magnetic measurements revealed that the samples are superparamagnetic at room temperature and the overall magnetic behavior is not affected by the functionalization process. Calorimetric measurements demonstrated a good heating efficiency at alternating magnetic field parameters below the human tolerability threshold (SAR of ca. 70 W/g at 260 Hz and 10.8 kA/m). H-1-NMR relaxivities were relevant compared to the values of the commercial contrast agents over the whole investigated frequency range.

The optical and magneto-optical (MO) properties of magneto-plasmonic nanocomposite films made up of a transparent polymer with a dispersion of cobalt ferrite (CFO) nanoparticles (NPs) and different concentrations of Au NPs are investigated. The volumetric concentrations of CFO and Au NPs, around 3%, and below 7‰ respectively, are below the percolation limit, and hence the nanocom-posite films constitute models for investigating the influence of the electromagnetic field generated at the surface plasmon resonance of Au NPs on the magneto-optical properties of CFO NPs. The plasmon resonance is present in these magneto-plasmonic composites, red-shifted with respect to the bare Au NPs and covering the spectral region where charge-transfer and crystal field MO transitions can be excited. Moreover, the magneto-optical hysteresis loops were measured in the whole spectral region. We observe that the hysteresis loops shape is a fingerprint of the different MO transitions of the CFO NPs. The strength of the MO peak around 750 nm, corresponding to the Crystal Field transition is damped respect to the corresponding peak of the CFO NPs. The strength of this peak evolves non-monotonically with the Au NPs concentration. On the other hand, the MO band around 550 nm, excited by Charge Transfer transitions, changes sign when Au NPs are present. In addition, a second MO contribution is observed. Our results demonstrate that the interactions between plasmon resonance and MO effects are not only determined by the stronger local electromagnetic fields at the resonance but they depend on the type MO transition that is involved in these oxides. This study helps to understand and design the magneto plasmonic nano-structures and applications, for example in biomedicine and sensing, in which random and weak dipolar interparticle interactions between plasmonic and magnetic nanostructures are present.

The new title binuclear Ni (II) compound (1) and the novel pentanuclear Ni (II) cluster {[ } (2) are formed from the reaction of an asymmetric Schiff base ligand L (L = 4-(salicylaldiminato)antipyrine) with Ni .4 in the former or Ni(ClO4)2.6H2O in presence of malonate in the later. Complex (1) consists of ( ]+ cation) and one uncoordinated tetraphenylborate anion. The cation adopts a distorted octahedral arrangement around each metal center. In the binuclear unit both Ni(II) ions are linked through two phenolate (µ2-O) oxygen atoms of L, and two oxygen atoms of a bridging carboxylate group. Each Ni (II) coordinates to four oxygen atoms at the basal plane, two oxygen atoms from two bridging phenolate groups, one from pyrazolone ring and the last of an aqua molecule, and at the axial positions to a bridging carboxylate-O atom and an azomethine nitrogen atom. In the pentanuclear cluster (2) consisting of [ ]+2 cation and two tetraphenylborate anions, the core of the cation is assembled by four [Ni( )] units, linked to the central Ni-ion by two bridging water molecules. The resulting coordination sphere for the external symmetry related nickel ions is a pseudo octahedron. The central Ni-atom unusually adopts dodecahedron geometry through its coordination to eight bridging water molecules. In complex (1) each Ni-atom is coordinated to one tridentate L ligand and in complex (2) each [Ni ( )] unit is coordinated to two bidentate L ligands. Inter-and intramolecular hydrogen bonds are present in both crystal structures.

Based on 1-(cyclohexylmethyl)-1H-tetrazole (C6mtz), a series of mononuclear iron(II) spin-crossover complexes with the general formula [Fe(C6mtz)6]X2, where X is the non-coordinating anion (1), (2), or (3), have been synthesized and characterized. Temperature-dependent magnetic susceptibility measurements for 1, 2, and 3 show reversible one-step spin crossover (SCO) behavior between high-spin (HS, S = 2) and low-spin (LS, S = 0) states without hysteresis. The compound shows spin transition at T1/2 = 213 K at a considerably higher temperature than the other compounds, (T1/2 = 126 K) and (T1/2 = 119 K). Temperature-dependent Far-IR and Mossbauer spectra of 2 and 3 were compared with the measured magnetic susceptibility and confirm the one-step SCO behavior of the compounds.

A survey about the characterization of molecular magnets adsorbed on surfaces by density functional methods studied in our laboratory is presented. Several computational issues afflict the description of the different players involved and, therefore, first a discriminating analysis of the single players and afterwards the scenario in which they interact are presented. An assessment of the applicable computational protocols describing the evolution of the magnetic properties of some molecular magnets from the bulk to the surface adsorbed scenario is presented. The limits of the approaches and their applicability are also discussed. In the framework proposed, the role of the surface and its effects on the geometry and the magnetic properties on the adsorbed molecular magnets are enlightened.

The use of engineered nanomaterials (ENMs) for environmental remediation, known as nanoremediation, represents a challenging and innovative solution, ensuring a quick and efficient removal of pollutants from contaminated sites. Although the growing interest in nanotechnological solutions for pollution remediation, with significant economic investment worldwide, environmental and human risk assessment associated with the use of ENMs is still a matter of debate and nanoremediation is seen yet as an emerging technology. Innovative nanotechnologies applied to water and soil remediation suffer for a proper environmental impact scenario which is limiting the development of specific regulatory measures and the exploitation at European level. The present paper summarizes the findings from the workshop: “Ecofriendly Nanotechnology: state of the art, future perspectives and ecotoxicological evaluation of nanoremediation applied to contaminated sediments and soils” convened during the Biannual ECOtoxicology Meeting 2016 (BECOME) held in Livorno (Italy). Several topics have been discussed and, starting from current state of the art of nanoremediation, which represents a breakthrough in pollution control, the following recommendations have been proposed: (i) ecosafety has to be a priority feature of ENMs intended for nanoremediation; ii) predictive safety assessment of ENMs for environmental remediation is mandatory; (iii) greener, sustainable and innovative nano-structured materials should be further supported; (iii) those ENMs that meet the highest standards of environmental safety will support industrial competitiveness, innovation and sustainability. The workshop aims to favour environmental safety and industrial competitiveness by providing tools and modus operandi for the valorization of public and private investments.

In iron oxide nanoparticles the transformation of the metastable magnetite phase to maghemite, through the oxidation of iron, often represents a major drawback for correct interpretation of their physical properties and their effective use in several applicative areas. To solve this issue we propose an innovative method for identifying the chemical composition of complex ferrite nanostructures based on magneto-optical (MO) spectroscopy. Spherical iron oxide nanoparticles with increasing size are investigated by magnetic circular dichroism (MCD) in the nUV-vis-nIR range (350-1000 nm). Particular attention is dedicated to the time evolution of the MO response, which is ascribable to the oxidation process of the nanomaterial. The measured MCD spectra show a complex line shape due to the overlap of several MO transitions. Deconvolution analysis of MCD hysteresis loops allows the interpretation of this complex response as the combination of two distinct contributions, originating from magnetite and maghemite domains in the nanoparticles. We consider this method a viable complement to conventional techniques for the discrimination of the two magnetic phases in nanostructured materials.

The reaction of the chromium(III) chloride tetrahydrofuran complex with the dipivaloylmethane ligand, the lanthanide alcoholic salt DyCl3·CH3OH and the 1,1,1-tris(hydroxymethyl)-ethane ligand resulted in the formation of a new trinuclear chromium–dysprosium complex. Magnetic investigations revealed that the new 3d–4f complex exhibits single molecule magnet behaviour.

[Fe(SB)(H2O)]ClO4 and [NEt4]3[Fe(CN)6] react in methanol to give a cis cyano-bridged assembly, 3D [NEt4][Fe(5-ClL1)]2[Fe(CN)6] (5-ClL1H2 = N,N′-bis(5-chlorosalicylidenato)-2,2-dimethyl-1,3-diaminopropane), 1, and a trans cyano-bridged trinuclear complex, [NEt4][Fe(5-ClL2)(MeOH)]2[Fe(CN)6] (5-ClL2H2 = N,N′-bis(5-chlorosalicylidenato)-1,2-diaminopropane), 2, depending on the Schiff base used. Complexes 1 and 2 have been characterized by X-ray analyses and magnetic measurements. The four CN− in the equatorial plane of the [Fe(CN)6]3− moiety bridge four Fe ions each in the cis position, which results in a 3D neutral layered structure giving a [–Fe–NC–Fe–CN–Fe–] linkage for 1. The two CN− in the equatorial plane of the [Fe(CN)6]3− moiety bridge two Fe ions, in the trans position, which results in a hydrogen bonded 2D neutral layered structure for 2. Magnetic studies reveal that complex 1 exhibits weak intralayer ferromagnetic coupling, while complex 2 displays transition to a 3D ferromagnetic order between low-spin Fe(III) and high-spin Fe(III) through the cyanide bridges. Complex 2 further displays frequency-dependent alternating current magnetic susceptibility.

We deposit a paramagnetic pyrene derivative of the nitronyl nitroxide radical on Si(111). The molecules experience a strong chemical interaction with the substrate that influences the film growth. We also study the time evolution of the nitronyl nitroxide radical under a micro-focused soft X-ray beam, observing a stable radical as a product. This result hints at the possibility of using this class of materials in dosimeters and sensors.