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Cu-substituted Ni ferrite systems are produced following a hydrothermal synthetic route carried out at relatively mild conditions (i.e., below 200 °C). Different degrees of substitution were investigated, ranging from bare Ni ferrite to a complete Cu-substituted system (by replacing 100% of Ni with Cu). Morphological and structural characterisations point out that the introduction of Cu in the Ni ferrite (below 50% substitution) causes a gradual reduction of the average diameter of the ferrite polyhedral nanoparticles maintaining the Ni ferrite structure. At higher content of Cu, instead, the morphology evolves toward the co-presence of iron oxides (magnetite and hematite) and copper oxide (tenorite), without the formation of bare Cu ferrite. The partially substituted Ni ferrite nanomaterials exhibit a mostly superparamagnetic behaviour in all samples, registering a reduction of the values of magnetisation saturation by increasing the Cu content. Transmission Mössbauer spectroscopy performed on these nanomaterials evidenced a gradual lowering of the Fe fraction occupying the octahedral sites and a consequent increment of the Fe fraction in the tetrahedral sites. Quantitative analysis confirms the gradual reduction of the Ni content within the ferrite samples, coupled with the opposite increment of the Cu content, whereas the Fe content is lower in the case of Ni75-Cu25 sample. This particular behaviour can be associated with the influence of Cu substitution in the Ni ferrite structure, with preferential replacement of Fe from the octahedral B-sites toward the tetrahedral A-sites.

Icephobic materials can prevent or reduce ice formation, e.g. by ensuring easy detachment, a desirable property for those applications where ice accumulation is critical to human safety. Herein, we develop a chitosan electrolyte hydrogel to create a bio-based surface with low ice adhesion. The chitosan electrolyte hydrogel is physically crosslinked and infused with salted water at concentrations from 4.5 to 30 g/L, including that of seawater (23 g/L). Depending on salt content in the hydrogel, we could obtain very low ice adhesion down to 140 kPa (at – 10°C). We hypothesize that the chitosan electrolyte hydrogel exploits the colligative properties of water avoiding the ice nucleation at the ice-hydrogel interface. To confirm the hypothesis, we investigate the chitosan electrolyte hydrogel structure by contact angles analysis, DSC, TGA, FTIR, XRD, and by rheometry for mechanical properties. We quantify the presence of non-freezing water, which creates a lubricating liquid water layer at the ice-hydrogel interface, affecting the ice detachment mechanism and lowering ice adhesion. In conclusion, the proposed chitosan electrolyte hydrogel presents a bio-based and cost-efficient strategy for ice detachment across various icing scenarios for systems operating in humid marine environments, such as offshore platforms and ships.

In this study, an alternative mixed hydro-solvothermal route has been investigated for the synthesis of magnetic iron oxide nanoparticles with anisotropic shape. The synthesis was performed at mild conditions (150 °C) in a water/2-propanol environment, using poly(ethylene glycol) (PEG400) as structure directing agent, sodium thiosulfate as reducing agent, and NaOH as precipitating agent. The resulting systems were characterized by combining morphological, structural, and magnetic techniques. Experimental results clearly demonstrate that magnetite/maghemite nanorods are preferentially obtained in water/PEG400 environment, whereas 2-propanol/PEG400 environment promotes the growth of magnetite/maghemite polyhedral systems. Interestingly, synthesis performed in a mixed hydro-solvothermal (i.e., water/2-propanol) environment favors the preferential growth of hematite phase.

In this chapter, the main advances in the valorization of shellfish derived biowaste are critically analyzed. The current European policy on (bio)waste management as well as the economy behind the European shellfish industry market (i.e., fundamental for the comprehension of the volumes of available biomass) are both introduced, providing a classification of the principal European shellfish products. Later, the chemical and structural composition of bivalves, cephalopods, and crustaceans shells is explained. Furthermore, the main relevant processes applicable to the shellfish solid waste for the isolation of useful chemicals are presented, with a view to propose a biorefinery model based on the most promising shellfish derived products, namely chitin and chitosan. Lastly, the technological applications of shellfish-derived products in the agri-food industry and in environmental clean-up processes are critically examined, and the most relevant literature discussed. Concerning the environmental applications, particular emphasis is dedicated to the challenging “waste for cleaning waste” vision. Analogously, the direct use of shellfish derived products in the agri-food industry is presented as an effective example of smart circular recycling.

This work reports on the light-induced heterogeneous photodegradation of four micro-contaminants (MCs): Carbamazepine (C), Flumequine (F), Ibuprofen (I), and Sulfamethoxazole (S), using two different heterogeneous advanced oxidation processes. The first one is the semiconductor photocatalysis, run in the presence of the suspension of a home prepared TiO 2 (TiO 2 HP); the second one is an heterogeneous photo-Fenton process run in the presence of a hybrid magnetic nanomaterial (MB3) with an iron oxides core and an organic shell made of bio-based substances (BBS) isolated from urban biowaste. The two materials work upon two different mechanisms and were already tested (and the action mechanism hypothesized) at the lab scale under model conditions: TiO 2 acts as photocatalyst through the photo-generation of hole/electron pairs able to give rise to oxidation and reduction reactions, whereas hybrid magnetic nanomaterial acts in the presence of H 2 O 2 by a photo-Fenton like mechanism. The results evidenced the better performances of TiO 2 HP (also better than the well-known reference TiO 2 P25). Preliminary photodegradation experiments carried out in a pilot plant under natural solar radiation confirmed the good results obtained with TiO 2 HP. Moreover, in the adopted experimental conditions, the Fe(II) leached from MB3 can be considered as responsible of the MCs degradation through a homogeneous photo-Fenton reaction, where MB3 act as iron reservoir.

In line with the Green Supply Chain Management, Sustainable Supply Chain Management and Natural-Resource-Based Views (NRBV), the present study is as further step of a long range research program initiated in 2004. The project aims to demonstrate municipal bio-waste (MBW) as feedstock to produce bio based chemicals alternative to fossil sourced products. Previous work demonstrated MBW as source of polymeric biosurfactants (BPS) with multiple properties for use in chemical and agriculture sectors. The present paper reports now a new BPS feature, i.e. that BPS are efficient active principles for soil remediation. The study involves three BPS obtained by alkaline hydrolysis from different streams of an MBW treatment plant: the anaerobic digestate of food kitchen waste (FORSUD), the compost (CV) of gardening residues and the compost (CVDF) of a mix of gardening residues, digestate and sewage sludge. The BPS have 5 to over 750 kg/mol molecular weight, characterized by the presence of aliphatic C chains substituted by aromatic moieties and several different acid and basic functional groups. They were used at 0.1–100 g L−1 in aqueous solution to wash soil sampled from an Italian metal polluted site. Collected data statistical analysis was carried out by ANOVA. The recovered washing solutions were analyzed for Cu, Cr, Ni, Zn, Pb. The 50–100 g/L CVDF BPS solutions exhibited 98-81% extraction efficiency, compared to 70-60% for CV and FORSUD. Compared to conventional commercial extractants, CVDF BPS extraction efficiency ranked as CVDF = diethylene triamine pentaacetic acid > ethylene diamine tetraacetic acid > sodium dodecyl sulphate. A new two steps process was studied: (1) use of BPS solution for washing the polluted soil; (2) treating the recovered solution by acidification and membrane filtration to separate a pollutant concentrate from water for further use. Results indicate membrane filtration more efficient and/or sustainable. They confirm BPS as value added produ

The valorization of low-cost biobased resources (such as biomasses and their derivatives) as alternative feedstock for the preparation of innovative sustainable materials allows both economic and environmental benefits, for instance when these materials enhance the photodegradation of organic pollutants in water remediation processes. This chapter presents the physicochemical features of biobased substances (BBS) isolated from urban organic residues, and it reports on their performances as chemical auxiliaries in advanced oxidation processes (AOPs). In the homogeneous phase, BBS can indeed promote the direct oxidation of organic pollutants through the formation of many reactive species, and it can also allow running Fenton and photo-Fenton processes at circumneutral pH. Additionally, BBS can be used in heterogeneous phase. In addition, the preparation, characterization, and pollutant photodegradation efficiency of novel heterogeneous systems based on hybrid magnet-responsive materials functionalized with biobased substances is discussed, whereas the functionalization with oxidative enzymes is presented as well.

Pyrolysis is the simplest method to convert bio-based materials into carbonaceous chars. In this study, Na alginate (an aquatic-derived substance isolated from brown algae) is thermally treated under very mild condition (onset temperature). The effectiveness of the conversion has been determined via physicochemical characterizations, showing the possibility of modifying the (bio)polymeric chemical structure just at the beginning of its thermal degradation, guaranteeing an overall energetic beneficial effect.

In this work, metallic silver flower-like and aerogel-like nanostructures deposited onto hydrophobic dielectric substrates (HF-treated Si and PDMS) showed interesting potentialities as solid SERS substrates aimed to high sensitive molecular detection and quantitation. In detail, the nanostructures were incubated in 4-MBA solutions at 10−2 M – 10−9 M concentrations. The quantitative analysis confirmed a monotonic increase of the SERS signal intensity as a function of the 4-MBA concentration, following a Langmuir model, thus suggesting a chemisorption phenomenon. The best homogeneity and adhesion strength in liquid media of Ag nanostructures to the solid substrates were reached for the flower-like systems and the aerogel-like ones compared to traditional polyhedral nanostructures (taken as reference substrate), thus making them extremely appealing as a solution for the development of SERS-based sensors.

Chitin (a biopolymer obtained from shellfish industry) was used as precursor for the production of biochars obtained via pyrolysis treatments performed at mild conditions (in the 290–540 °C range). Biochars were physicochemical characterized in order to evaluate the pyrolysis-induced effects in terms of both functional groups and material structure. Moreover, such carbonaceous materials were tested as adsorbent substrates for the removal of target molecules from aqueous environment as well as in solid-gas experiments, to measure the adsorption capacities and selectivity toward CO2. Lastly, biochars were also investigated as possible cathode materials in sustainable and low-cost electrochemical energy storage devices, such as lithium-sulphur (Li-S) batteries. Interestingly, experimental results evidenced that such chitin-derived biochars obtained via pyrolysis at mild conditions are sustainable, low-cost and easy scalable alternative materials suitable for both environmental and energetic applications.

In this study, chitosan and bio-based substances (BBS) obtained from composted biowaste were used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs) via coprecipitation method. A pyrolysis treatment was carried out on both biopolymers at 550 °C, and their consequent conversion into a carbon matrix was followed by means of different physicochemical characterization techniques (mainly FTIR spectroscopy and XRD), whereas magnetic properties were evaluated by magnetization curves. The prepared materials were tested in water remediation processes from arsenic (As) species (both inorganic and organic forms). These tests, explained by means of the most common adsorption models, evidenced that the best performances were reached by both materials obtained after pyrolysis treatments, pointing out the promising application of such magnet-sensitive materials as easy-recoverable tools for water purification treatments.

In this study, bio-based substances (BBS) obtained from composted urban biowaste are used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs). The BBS-stabilized NPs are characterized by means of different techniques (FTIR, XRD, SEM, BET analysis, magnetization curves). Additionally, TGA coupled on-line with FTIR and GC/MS analysis of the exhausted gas are performed in order to simultaneously identify all the degradation products and evaluate the exact composition of such BBS-stabilized materials. Moreover, Fenton-like or photo-Fenton-like experiments carried out at circumneutral pH are performed in order to evaluate the BBS-functionalized NPs photo-activity towards the degradation of caffeine (taken as model emerging pollutant). The obtained promising results encourage the use of BBS as a green alternative tool for the preparation of smart materials with enhanced magnet-sensitive properties, also suitable for applications in wastewater purification treatments.

The adsorption of dissolved organic carbon (DOC) on iron (Fe) (hydr)oxides represents an important stabilization mechanism for soil organic matter (OM) and contributes to soil C accumulation. However, in soils that experience periodic fluctuations in redox conditions the interaction between DOC and Fe (hydr)oxides may not only involve organic coatings on mineral surfaces, but also Fe-DOC coprecipitates that form during the oxidation of soil solutions containing important amounts of DOC and Fe2+. The aim of this work is to provide new insights into the mechanisms involved, and the amount and selectivity of C retained during the coprecipitation process. A series of Fe-OM associations with increasing C loading was synthesized at pH 6 by surface adsorption or coprecipitation (oxidation of ferrous iron) utilizing rice-straw derived dissolved organic matter. The kinetics of Fe2+ oxidation and complexation, and the total and selective retention of DOC during the coprecipitation process were evaluated. Moreover, synthesized associations, as well as a field coprecipitate collected in situ from a paddy soil, were studied by X-ray diffraction, N2 gas adsorption-desorption isotherms, electrophoretic mobility measurements and thermogravimetric analyses. Coprecipitation resulted in higher organic C contents (49–213 mg g−1) with respect to adsorbed systems (18–47 mg g−1), and favoured the inclusion of OM within highly aggregated associations having particularly low BET specific surface areas. Although coprecipitation led to a strong, selective retention of aromatic constituents, the initial complexation of Fe2+ by aliphatic carboxylic moieties and precipitation as C-rich Fe-OM associations contributed to the total C retention, particularly at higher solution C/Fe ratios. These aliphatic complexes formed during coprecipitation may play an important, though often underestimated, role in C stabilization in soils experiencing frequent redox fluctuations and often characterized by elev

Poly(vinyl alcohol-co-ethylene) was compounded with 2e10% post-harvest tomato (PHT) plant powder and processed by single-screw extrusion to yield composite films. Upon increasing the filler content, the values of the mechanical properties indicators were found to decrease as follows: Young's modulus from 1797 to 750 MPa, stress at yield from 36 to 15 MPa, maximal stress from 39 to 15 MPa, stress at break from 35 to 14 MPa, and strain at break from 6.6 to 4.3%. The results are discussed in comparison with other composite films containing poly(vinyl alcohol-co-ethylene) and water soluble biopolymers obtained by alkaline hydrolysis of fermented municipal biowastes, and with other commercial materials, such as starch based and low density polyethylene mulch films. Depending on the intended application, the post-harvest tomato blend films may be competitive for cost, performance and sustainability.

The aim of this review is to clarify the importance of surface modifications induced in biomaterials for hernia-repair application. Starting from the pioneering experiences involving proto-materials as ancient prosthesis, a historical excursus between the biomaterials used in hernioplasty was realized. Subsequently, after the revolutionary discovery of stereoregular polymerization followed by the PP application in the biomedical field performed by the surgeon F. Usher, a comparative study on different hernia-repair meshes available was realized in order to better understand all the outstanding problems and possible future developments. Furthermore, since many unsolved problems on prosthetic devices implantation are linked to phenomena occurring at the interface between the biomaterials surface and the body fluids, the importance of surface science in hernioplasty was highlighted and case studies of new surface-modified generations of prosthesis presented. The results discussed in the following evidence how the surface study are becoming increasingly important for a proper knowledge of issues related to the interaction between the living matter and the artificial prostheses.

Porous materials are powerful functional devices that can find applications in many fields, from nanotechnology to biomedicine, from catalysis to membrane separation. In general, porous materials can be processed in various forms, but a rising interest is growing around inorganic thin films and coatings, due to the increased number of applications based on their use. Among the different strategies proposed till now for preparing inorganic porous thin layers/coatings, a simple and versatile route consists in the combined use of sol-gel chemistry, templating, and spin-coating deposition. Therefore, in order to provide a helpful toolbox for users, an extended discussion around the physico-chemical principles behind each of these steps is here reported, also highlighting the advantages and disadvantages of each procedure, together with critical points.

In this study, a magnetic iron oxide–chitosan composite film is synthesized by one-step method and thoroughly investigated in order to better understand its inorganic/organic properties. A deep physico-chemical characterization of the magnetic films has been performed. In particular, the material composition was evaluated by means of XRD and ATR-FTIR spectroscopy, whereas the thermal stability and the subsequent inorganic phase transitions involving iron oxide species were followed by TGA analyses carried out at different experimental conditions (i.e. inert and oxidative atmosphere). The magnetic properties of the films were tested at the bulk and at the surface level, performing respectively magnetization hysteresis curve and magnetic force microscopy (MFM) surface mapping. Results indicate that the synthesized material can be prepared through a very simple synthetic procedure and suggests that it can be successfully applied for instance to environmental applications, such as the adsorption of contaminants from solid and liquid media thanks to its pronounced magnetic properties, which favourits recover.

Hernia diseases are among the most common and diffuse causes of surgical interventions. Unfortunately, still nowadays there are different phenomena which can cause the hernioplasty failure, for instance post-operative prostheses displacements and proliferation of bacteria in the surgical site. In order to limit these problems, commercial polypropylene (PP) and polypropylene/Teflon (PP/PTFE) bi-material meshes were surface functionalised to confer adhesive properties (and therefore reduce undesired displacements) using polyacrylic acid synthesized by plasma polymerisation (PPAA). A broad physico-chemical and morphological characterisation was carried out and adhesion properties were investigated by means of atomic force microscopy (AFM) used in force/distance (F/D) mode. Once biomedical devices surface was functionalised by PPAA coating, metallic silver nanoparticles (AgNPs) with antimicrobial properties were synthesised and loaded onto the polymeric prostheses. The effect of the PPAA, containing carboxylic functionalities, adhesive coating towards AgNPs loading capacity was verified by means of X-ray photo-electron spectroscopy (XPS). Preliminary measurement of the Ag loaded amount and release in waterwere also investigated via inductively coupled plasma atomic emission spectroscopy (ICP-AES). Promising results were obtained for the functionalised biomaterials, encouraging future in vitro and in vivo tests.

Highly selective membranes with controlled porosity can be obtained by growing thin films of mesoporous oxides on an appropriate support. This can be achieved employing organic/inorganic mixed micellar solutions based on metal oxide precursors and commercial templates. In particular amphiphilic block copolymers are very attractive materials as soft-templating agents because they self-assemble into micelles whose morphology and size depend on block composition and solution parameters. Large-mesopore silica films with narrow pore size distribution and high porosity have been obtained by sol–gel reaction of a silicon oxide precursor (TEOS) and using polystyrene-block-poly(ethylene-oxide) (PS-b-PEO) copolymers as templates. In order to modulate size, shape and alignment of the pores, many variables were changed: block copolymer chain length, TEOS/block copolymer ratio, solvent ratio, additives (i.e. polystyrene homopolymer addition). The effect of the different parameters on the porous system was studied by microscopy techniques and gas-volumetric analyses. Final aim of this work is the preparation of silica membranes to be used as selective gates for controlled dosing and transport of chemical species in solution.

Atmospheric Pressure Plasma-Dielectric Barrier Discharge (APP-DBD, open chamber configuration) was used to functionalize polypropylene (PP) fibers surface in order to generate oxidized-reactive groups such as hydroperoxides, alcohols and carbonyl species (i.e. ketones and others). Such a species increased the surface polarity, without causing material degradation. Three different types of plasma mixture (He, He/O2, He/O2/H2O) under three different values of applied power (750, 1050, 1400 W) were investigated. The formed plasma species (O2+, O single atom and OH radical) and their distribution were monitored via Optical Emission Spectrometry (OES) measurements, and the plasma effects on PP surface species formation were followed by X-ray Photoemission Spectroscopy (XPS). Results allowed to better understand the reaction pathways between plasma phase and PP fibers. In fact, two reaction mechanisms were proposed, the first one concerning the plasma phase reactions and the second one involving material surface modifications.

Polypropylene (PP) fibers can be manufactured to form nets which can find application as prosthesis in hernioplasty. One of the most important problem to deal with when nets are applied in vivo consists in the reproduction of bacteria within the net fibers intersections. This occurs right after the application of the prosthesis, and causes infections, thus it is fundamental to remove bacteria in the very early stage of the nets application. This paper deals with the physico-chemical characterization of such nets, pre-treated by atmospheric pressure plasma dielectric barrier discharge apparatus (APP-DBD) and functionalized with an antibiotic drug such as chitosan. The physico-chemical characterization of sterilized nets, before and after the functionalization with chitosan, was carried out by means of scanning electron microscopy (SEM) coupled with EDS spectroscopy, FTIR spectroscopy, drop shape analysis (DSA), X-ray diffraction and thermal analyses (TGA and DSC). The aim of the work is to individuate a good strategy to characterize this kind of materials, to understand the effects of polypropylene pre-treatment on functionalization efficiency, to follow the materials ageing in order to study the effects of the surface treatment for in vivo applications.