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Life Cycle Assessment is a structured and internationally standardized analytical tool to quantify all relevant emissions and consumed resources (ISO 14040-14044). Using Life Cycle Assessment is possible to analyze issues related to environmental and health impacts, and to the depletion of resources, associated with any good or process. Life Cycle Assessment covers the whole chain starting from the mineral extraction, and passing through the production, the use, the recycling, up to the disposal of the final wastes. This approach is known as "cradle to grave" analysis, indicating that the environmental impacts of the entire life cycle of products is considered. However, in research field, the typical approach is a "cradle to gate" analysis, where some phases are not considered, such as the use and the end of life ones, for instance. Life Cycle Assessment studies of experimental activities are useful to identify the critical steps in terms of environmental impacts and can be useful to support the design and the optimization of the experimental set-ups, addressing to more sustainable laboratory activities. In this work, a "cradle to gate" Life Cycle Assessment was carried out analyzing the experimental campaign of aluminum titanium nitride coating of commercial steel sheets by reactive physical vapor deposition magnetron sputtering. Aluminum titanium nitride is widely used material in many industrial fields as wear resistant coating in cutting tools, in bio-implants, in the aero-engine sector, as diffusion barriers in integrated circuits. The Physical Vapor Deposition is a scalable technique, and an environmental impact analysis assuming a great importance thinking to a technology transfer. Life Cycle Assessment is a suitable tool for this purpose, and it has been already widely used in many scientific, industry and policy sectors. Life Cycle Assessment results highlighted that the main driver of environmental impacts of the laboratory activities was the electricity used for instruments operations. The most energy consuming impact is related the vacuum keeping in the deposition chamber. In the second part of this study, several optimization strategies were evaluated to reduce the overall electricity consumption, with the aim of improving the environmental profile of experimental activities.

The goal of the study was to identify the environmental hotspots of a lab scale experimental campaign of AlTiN based magnetron sputtering thin film deposition onto laminated steel. Results highlighted that the main impacts were related to the electricity consumed in instruments operations. Several optimization strategies were evaluated to reduce the overall impacts, and to improve the environmental profile of the lab activity.

The broad blooming of strelitzia-like titanium oxide nanopetals was obtained onto single wall carbon nanostructures by the synergistic employment of two vapor techniques: metal-organic chemical vapor deposition (MOCVD) and magnetron sputtering 1. The nanocomposite photocatalyst exhibited a significant increase of phenol degradation efficiency under UV light irradiation with respect to the bare titanium oxide thin films deposited via RF magnetron sputtering and the titanium oxide coated carbon nanostructures via MOCVD 2,3. The hybrid nanostructured material was characterized by scanning electron microscopy and X-ray diffraction and its peculiar synthesis conditions were discussed.

AlTiN thin film deposition process was carried out via reactive Physical Vapor Deposition High-Power Impulse Magnetron Sputtering (PVD HiPI MS) with the aim of highlighting the criticalities which can occur during the coating Ti6Al4V parts realized via Selective Laser Melting (SLM). The conditions of PVD HiPIMS deposition process were adjusted in order to optimize the matching between the polished metallic substrates and the ceramic coatings. The effect of vacuum annealing at 950 degrees C onto the coated sample features was also evaluated. X-ray Diffraction, Energy Dispersive Spectroscopy associated to Field Emission Scanning Electron Microscopy (FE-SEM), profilometry, and nanoindentation were employed for carrying out a complete characterization of the film/substrate system.

This work reports the preliminary results of AlTiN hard coating deposition process carried out via reactive Physical Vapor Deposition High-Power Impulse Magnetron Sputtering (PVD HiPIMS), with the aim of improving the surface features of Ti6Al4V substrates, realized via Selective Laser Melting (SLM). Additive manufacturing (AM) is a bottom-up technology that could be the answer to particular needs, supporting the rapid fabrication of components with complex shapes. The choice of Ti-6Al-4V alloy is justified by the spread use of this alloy in several fields, such as the biomedical and aerospace ones [1]. On the other hand, AlTiN based hard films are widely used in many industrial applications (such as cutting tools, aero-engine sector, bio-implants, etc.) for their excellent wear and corrosion resistance properties up to 900°C [2-6]. In particular, two different SLM process conditions were employed for modifying the obtained part surface morphology and, later, the samples were heat treated in high vacuum. The conditions of the deposition process were adjusted in order to optimize the matching between the metallic substrate and the ceramic coating .

As a number of studies have already proven, metal parts manufactured through Additive Manufacturing (AM) show mechanical properties comparable to those of components produced by traditional methods. This applies for several metallic materials, both with regard to static stress resistance and fatigue strength. On the other hand, other properties, as the physicochemical ones, are still under evaluation. This work belongs to this research field since aimed at collecting data concerning the corrosion behaviour of AISI 316L samples manufactured, using pre-alloyed powders, through Laser Metal Fusion (LSM). In order to pursue the objectives of the investigation, the samples were subjected in the 'as printed' state to corrosion resistance tests through polarisation and Electrochemical Impedence Spectroscopy (EIS). In addition, the microstructures of "as printed" samples and samples surfaces before and after the electrochemical tests were characterised by Light Optical Microscopy (LOM) and Scanning Electron Microscopy equipped with microprobe for Energy Dispersive X ray Fluorescence (SEM-EDS).

Possibilities to use conjugated polymers as thermoelectric materials have been widely explored in the last few years, giving rewarding results1,2. Such materials are particularly appealing for room temperature application and flexible devices. Since the main drawback in conjugated polymer thermoelectric application is their low efficiency, several different paths have been explored in order to optimize performances3,4. Among them, the development of copolymers is still a mostly unexplored field, due to the increase of the system complexity that they involve. Although the challenge that they represent under a solid-state physics point of view, copolymers are also a novel chance to gain new information about thermoelectric related features in conjugated polymers. Copolymers mainly used for this purpose are copolymers within two different categories. On one side there are donor-acceptor copolymers5, on the other conjugated-not conjugated copolymers6, or partially conjugated copolymers. An overview of the state of art will be given, in order to collect the results currently achieved in this field considering both categories, with a particular attention to synthetic strategies and performance enhancing procedures adopted. Specifically, the thermoelectric behaviour of a novel poly(3,4-ethylenedioxythiophene) (PEDOT) based copolymer (Figure 1) and its blends with PEDOT:tosylate will be presented and discussed. Such derivative belongs to the second category and the study of thermoelectric properties of its blends with the pristine PEDOT has shown that charge transport is percolative (Figure 2). Percolation (Figure 3) can be a key to tune the organic material thermoelectric properties in order to achieve better performances. The results obtained will be discussed in the light of such purpose and possible future developments will be presented. [1] Q. Wei, M. Mukaida, K. Kirihara, Y. Naitoh and T. Ishida, Materials (Basel)., 2015, 8, 732-750. [2] B. Russ, A. Glaudell, J. J. Urban, M. L. Chabinyc and R. A. Segalman, Nat. Rev. Mater., 2016, 1, 16050. [3]O. Bubnova, Z. U. Khan, A. Malti, S. Braun, M. Fahlman, M. Berggren and X. Crispin, Nat. Mater., 2011, 10, 429-33. [4] S. K. Yee, N. E. Coates, A. Majumdar, J. J. Urban and R. A. Segalman, Phys. Chem. Chem. Phys., 2013, 15, 4024. [5] Y. Hiroshige, M. Ookawa and N. Toshima, Synth. Met., 2006, 156, 1341-1347. [6] P. S. Taylor, L. Korugic-Karasz, E. Wilusz, P. M. Lahti and F. E. Karasz, Synth. Met., 2013.

I pezzi metallici prodotti tramite tecniche di Manifattura Additiva (AM), così come molti studi hanno dimostrato, presentano proprietà meccaniche comparabili a quelle dei componenti prodotti secondo metodi tradizionali e questo vale, per molti materiali metallici, sia per le caratteristiche di resistenza a sollecitazioni statiche sia per quanto concerne la resistenza a fatica. Per contro altre proprietà, come quelle chimico-fisiche, sono ancora in fase di valutazione. Il presente lavoro si inserisce in questo settore della ricerca poiché ha avuto lo scopo di raccogliere dati circa il comportamento a corrosione di campioni in acciaio AISI 316L realizzati tramite Laser Metal Fusion (LSM) utilizzando polveri prelegate. Per perseguire gli obiettivi dell'indagine, i campioni sono stati sottoposti a test di resistenza alla corrosione tramite polarizzazione e spettroscopia di impedenza elettrochimica (EIS) nello stato tal quale (ovvero "as printed"). Inoltre, le microstrutture dei pezzi "as printed" e le loro superfici prima e dopo i test elettrochimici sono state caratterizzate tramite Microscopia Ottica (LOM) e Microscopia Elettronica a Scansione equipaggiata con microsonda per analisi di Fluorescenza di Raggi X in Dispersione di Energia (SEM-EDS).

Titanium and its alloys have been widely used for dental implants due to their non-toxicity, biocompatibility, corrosion resistance, and mechanical properties. In order to improve osseointegration, the Ti surface is generally functionalised. A typical methodology for surface modification is the coating of the Ti substrates with bioactive layers of calcium phosphate ceramics (CPCs). However, CPC coatings on metal implant usually suffer from poor adhesion. With the aim of improving the adhesion strength, the insertion of dense and compact ceramic interlayers is reported to be useful. Among various ceramics, crystalline titania (TiO2) has been extensively used as an interlayer thanks to its well-known biocompatibility and bioactivity. In this work, a new synergic deposition route for the osteointegrative functionalisation of Ti dental implants is proposed. Three types of Ti substrates (machined, sandblasted, and sandblasted/acid etched) were initially coated with a crystalline, dense and compact TiO2 interlayer via MOCVD. Then, a discontinuous and homogenously spread CPC top-layer was obtained by means of spray pyrolysis technique. Finally, a thermal treatment at high temperature was carried out in order to crystallize the final composite material. The influence of the pristine substrate morphology on the crystalline structures and morphology of the coatings is here presented. Moreover, surface wettability, ions release and in vitro acellular bioactivity have also been evaluated.

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Thermoelectric materials can convert heat into electricity when a temperature gradient is present. The investigation of conductive polymers such as polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) as active materials for thermoelectric generators in the room temperature range is gaining interest because of several key advantages offered by these materials. The relative ease of solution processing, their mechanical stability and flexibility together with low density and low thermal conductivity make conductive polymers suitable for integration in a thermoelectric generator. Polymers offer remarkably low thermal conductivity values but modest Seebeck coefficient and electrical conductivity. In this work, polymer/inorganic nanocomposites of PANI with carbon particles such as single wall carbon nanohorns (SWCNHs) were prepared via solution mixing of the precursors in order to increase the electrical conductivity by means of polymer matrix/nanohorn electronic junctions. The electrical conductivity and Seebeck coefficient were estimated on PANI/SWCNH films and pressed pellets and through-plane thermal conductivity was determined on films. The thermal stability of PANI/SWCNH composites was evaluated by means of TGA/DSC coupled with residual gas analysis. It was found that a proper concentration of SWCNHs in PANI-(+/-)-camphor-10-sulfonic acid (CSA) film was effective in increasing the electrical conductivity without decreasing the Seebeck coefficient.

Titanium and its alloys have been widely used for dental implants due to their excellent combination of strength-to-weight ratio, excellent corrosion resistance and biocompatibility [1]. A surface feature of Ti is the capability to spontaneously form a thin (4-6 nm) stable amorphous TiO2 film. Despite the excellent biocompatibility of the native oxide film, this oxide is known to seldom bond chemically to bone tissue [2 and ref. therein]. Various techniques have been developed in order to grow up TiO2 layers with improved characteristics with respect to the native layer: deposited rutile and anatase layers compared to native TiO2 show enhanced bone-like precipitation at the surface in simulated body fluids. MOCVD technique has been applied to the growth of TiO2 coatings, which successfully underwent several biological tests [2 and ref. therein]. However, the influence of the TiO2 MOCVD coating on the bioactivity of Ti substrate with peculiar pristine morphology has been weakly explored. In this regard, besides to the chemical surface composition, the roughness and the topography of the Ti surface are significant parameters that affect the rate and quality of osseointegration. In this work, three types of Ti substrates (machined, sandblasted, and sandblasted/acid etched) with different morphology were coated with 200 nm titanium oxide films by using MOCVD, operating at 350°C and 100 Pa. The influence of the pristine substrate morphology on TiO2 crystalline structure, morphology, surface wettability and bioactivity is here presented. It is shown that the specific morphology of the substrate influences both the crystalline phase of the TiO2 and the crystallite size. SEM analysis shows an optimal conformal coverage of the coating for all substrates, with specific grain size as a function of the substrate morphology. Even the wettability depends on the Ti substrate features, demonstrating a superhydrophilic behaviour for the sandblasted/acid etched samples after MOCVD deposition. Finally, bioactivity experiments were carried out in order to evaluate the influence of substrate morphology on the bioactivity of the TiO2/Ti samples in simulated body fluid (SBF).

Tetrahedrite mineral family, one of the most widespread sulfosalts on Earth's crust, seems to meet the right features for an attractive sustainable p-Type Pb-free thermoelectric material, showing relatively high conversion efficiency, achieving a figure of merit value of almost 1 at 450°C [1,2]. In this work, Ni-Zn co-doped tetrahedrite samples were prepared by Open Die Pressing one step reactive consolidation method [3], employing previously ball milled sulphide powder precursors, in order to identify a simple cheap scalable fast production route for thermoelectric pellets. The influence of dopant presence and reactive consolidation process parameters on the tetrahedrite phase content, stoichiometry and density of the samples were investigated by X-ray diffraction, scanning electron microscope (equipped with energy dispersive Xray spectroscopy), and thermogravimetric analysis. Laser Flash Analysis, electrical conductivity, and Seebeck coefficient measurements were carried out for obtaining a complete thermoelectric characterization.

The interest in thermoelectric materials raised in the recent years due to the possibility to design thermoelectric generators (TEGs), reliable solid-state devices for waste heat recovery valuable in particular contexts where the employment of other technologies results inconvenient. Nowadays, the challenge in the thermoelectric field seems to be the identification of efficient thermoelectric materials which should be also inexpensive, easy to synthesize, and comprised of earth-abundant elements. On this basis, tetrahedrite mineral family (Cu12-xTrxSb4S13 where, for instance, Tr could be Mn, Fe, Co, Ni, or Zn), one of the most widespread sulfosalts on Earth's crust, seems to meet the right features for an attractive sustainable p-Type Pb-free thermoelectric material showing relatively high conversion efficiency [1,2]. The sulphide precursor powders were ball milled and then one-step simultaneous synthesis and sintering process was performed by open die pressing (ODP) [3]. By this simple, fast, and easy scalable route, thermoelectric pellets with a whole process lasting less than 6 hours. Both Zn and Ni cations were added as partial substituents of Cu in Cu12Sb4S13 permitting to considerably improve the thermoelectric performances of the undoped material prepared by ODP. The influence of precursor ratio on the tetrahedrite phase, secondary phase content and stoichiometry were investigated by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. The density and mechanical stability of samples were evaluated as a function of the chemical composition and processing parameters. A complete thermoelectric characterization was carried out for samples with different Zn and Ni substitution up to 400 °C.

Thermoelectric (TE) materials can convert heat into electricity when a temperature gradient is present. The investigation of conductive polymers such as polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) (PEDOT) as active materials for thermoelectric generators in the room temperature range is gaining interest because of several key advantages offered by these materials. The relative easiness of solution processing, their mechanical stability and flexibility together with low density and low thermal conductivity make conductive polymers suitable for integration in a thermoelectric generator. Polymers offer remarkably low thermal conductivity values but modest Seebeck coefficient and electrical conductivity. Polymer/inorganic composites of PANI were produced by adding high-conductive single wall carbon nanohorns (SWCNHs) or thermoelectric metal chalcogenides nanoparticles belonging to the tetrahedrite family Cu12Sb4S13 as fillers to improve the thermoelectric performance by means of polymer matrix/inorganic particle electronic junction. Electrical conductivity, Seebeck coefficient and thermal conductivity were estimated on PANI-based composite films and pressed pellets. The thermal stability was evaluated by means of thermogravimetric analysis/differential scanning calorimetry coupled with residual gas analysis .

The interest in thermoelectric materials raised in the recent years due to the possibility to design thermoelectric generators (TEGs), reliable solid-state devices for waste heat recovery valuable in particular contexts where the employment of other technologies results inconvenient. Nowadays, the challenge in the thermoelectric field seems to be the identification of efficient thermoelectric materials, which should be also inexpensive, easy to synthesize, and comprised of earth-abundant elements. On this basis, tetrahedrite mineral family (Cu12-xTrxSb4S13 where Tr= Mn, Fe, Co, Ni, Zn), one of the most widespread sulfosalts on Earth's crust, seems to meet the right features for an attractive sustainable p-Type Pb-free thermoelectric material showing relatively high conversion efficiency. The sulphide precursor powders were ball milled and then one-step simultaneous synthesis and sintering process was performed by open die pressing (ODP). By this simple, fast, and easy scalable route, thermoelectric pellets with a whole process lasting less than 6 hours. Both Zn and Ni cations were added as partial substituents of Cu in Cu12Sb4S13 permitting to considerably improve the thermoelectric performances of the undoped material prepared by ODP. The influence of precursors ratio on the tetrahedrite phase, secondary phase content and stoichiometry were investigated by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. The density and mechanical stability of samples were evaluated as a function of the chemical composition and processing parameters. A complete thermoelectric characterization was carried out for samples with different Zn and Ni substitution up to 400°C.

Many conventional thermoelectric materials are anisotropic: the structural complexity, useful to improve the material efficiency, often leads to a strong dependence of the material properties on the different spatial direction considered. This aspect, lately subject of increasing interest, has been often neglected in the study of polycrystalline samples, because of their randomly oriented grain structure. Recently, looking for further improvements in thermoelectric efficiency, techniques for the sintering of polycrystalline samples able to preserve the natural anisotropy of the compounds have been studied and developed. The common target is to produce bulk samples easier to deal with as respect to single crystals, with improved thermal and mechanical properties, preserving the optimal electrical characteristics. In some cases, the latter depending on the crystallographic direction considered. The present work reports the results obtained for material fast sintering and texture inducing using open die pressing technique, focusing on the effects produced by the mechanical processing. The open die pressing results to be effective in the fast sintering of different classes of materials. The process is easily scalable and does not require special expensive facilities. It also induces a strong texturing effect in the polycrystalline bulks preserving the anisotropy of electrical properties. Both structural analyses and microscopy display strong orientation of the material after sintering. Here, recent results obtained on sintering SnSe and tetrahedrites powders are reported.

Tetrahedrite mineral family, one of the most widespread sulfosalts on Earth's crust, seems to meet the right features for an attractive sustainable p-Type Pb-free thermoelectric material, showing relatively high conversion efficiency, achieving a figure of merit value of almost 1 at 450°C [1,2]. In this work, Ni-Zn co-doped tetrahedrite samples were prepared by Open Die Pressing one step reactive consolidation method [3], employing previously ball milled sulphide powder precursors, in order to identify a simple cheap scalable fast production route for thermoelectric pellets. The influence of dopant presence and reactive consolidation process parameters on the tetrahedrite phase content, stoichiometry and density of the samples were investigated by X-ray diffraction, scanning electron microscope (equipped with energy dispersive X-ray spectroscopy), and thermogravimetric analysis. Laser Flash Analysis, electrical conductivity, and Seebeck coefficient measurements were carried out for obtaining a complete thermoelectric characterization. Acknowledgments The authors are grateful to Stefano Boldrini (CNR-ICMATE) for the valuable discussion about the results, to Enrico Bassani (CNR-ICMATE) for his essential technical supports, and Raul Carampin (CNR-IGG) for the inestimable help, advices and data discussion about the quantitative EDS analyses. This work has been funded by the Italian National Research Council - Italian Ministry of Economic Development Agreement "Ricerca di sistema elettrico nazionale". References: [1]X. Lu, D.T. Morelli, Physical Chemistry Chemical Physics 15 (2013) 5762. [2]X. Lu, D.T. Morelli, Y. Xia, V. Ozolins, Chemistry of Materials 27 (2015) 408. [3]S. Ceresara, C. Fanciulli, F. Passaretti, D. Vasilevskiy, Journal of Electronic Materials 42 (2013) 1529.