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Inspired by the increasing desire to mimic the perfection of nature, micro- and nanorobots are triggering increasing interest among the scientific community. The development of such tiny machines that can autonomously perform specific and various tasks at a small scale has reached a high-level of complexity over the last 15 years although the transition from hard to soft self-propelled architectures has had the most profound impact. The use of organic components, such as polymers, is of particular interest to fulfill the lack of biocompatibility and biodegradability of inorganic-based microrobots. Additionally, the combination of self-powered micro- and nanorobots with some macromolecules' ability to be deformed and respond to external stimuli is an important topic. This review aims to critically assess the fundamental aspects of smart machines composed of polymers, examine recent advances in the combined systems at the micro- and nanoscale, and discuss the specific contribution of several polymer families. This review elucidates the role of smart polymers in the expanding field of intelligent micromachines.

Titanium miniplates are biocompatible materials used in modern oral and maxillofacial surgery to treat facial bone fractures. However, plate removal is often required due to implant complications. Among them, a biofilm formation on an infected miniplate is associated with severe inflammation, which frequently results in implant failure. In light of this, new strategies to control or treat oral bacterial biofilm are of high interest. Herein, the authors exploit the ability of nanorobots against multispecies bacterial biofilm grown onto facial commercial titanium miniplate implants to simulate pathogenic conditions of the oral microenvironment. The strategy is based on the use of light-driven self-propelled tubular black-TiO2/Ag nanorobots, that unlike traditional ones, exhibit an extended absorption and motion actuation from UV to the visible-light range. The motion analysis is performed separately over UV, blue, and green light irradiation and shows different motion behaviors, including a fast rotational motion that decreases with increasing wavelengths. The biomass reduction is monitored by evaluating LIVE/DEAD fluorescent and digital microscope images of bacterial biofilm treated with the nanorobots under motion/no-motion conditions. The current study and the obtained results can bring significant improvements for effective therapy of infected metallic miniplates by biofilm.

Nature presents the collective behavior of living organisms aiming to accomplish complex tasks, inspiring the development of cooperative micro/nanorobots. Herein, the spontaneous assembly of hematite-based microrobots with different shapes is presented. Autonomous motile light-driven hematite/Pt microrobots with cubic and walnut-like shapes are prepared by hydrothermal synthesis, followed by the deposition of a Pt layer to design Janus structures. Both microrobots show a fuel-free motion ability under light irradiation. Because of the asymmetric orientation of the magnetic dipole moment in the crystal, cubic hematite/Pt microrobots can self-assemble into ordered microchains, contrary to the random aggregation observed for walnut-like microrobots. The microchains exhibit different synchronized motions under light irradiation depending on the mutual orientation of the individual microrobots during the assembly, which allows them to accomplish multiple tasks, including capturing, picking up, and transporting microscale objects, such as yeast cells and suspended matter in water extracted from personal care products, as well as degrading polymeric materials. Such light-powered self-assembled microchains demonstrate an innovative cooperative behavior for small-scale multitasking artificial robotic systems, holding great potential toward cargo capture, transport, and delivery, and wastewater remediation.

Magnetic nanorobots offer wireless navigation capability in hard-to-reach areas of the human body for targeted therapy and diagnosis. Though in vivo imaging is required for guidance of the magnetic nanorobots toward the target areas, most of the imaging techniques are inadequate to reveal the potential locomotion routes. This work proposes the use of radiopaque magnetic nanorobots along with microcomputed tomography (microCT) for localized in vivo imaging applications. The nanorobots consist of a contrast agent, barium sulfate (BaSO

Antibiotics are antimicrobial substances that can be used for preventive and therapeutic purposes in humans and animals. Their overdose usage has led to uncontrolled release to the environment, contributing significantly to the development of antimicrobial resistance phenomena. Here, enzyme-immobilized self-propelled zinc oxide (ZnO) microrobots are proposed to effectively target and degrade the released antibiotics in water bodies. Specifically, the morphology of the microrobots is tailored via the incorporation of Au during the synthetic process to lead the light-controlled motion into having on/off switching abilities. The microrobots are further modified with laccase enzyme by physical adsorption, and the immobilization process is confirmed by enzymatic activity measurements. Oxytetracycline (OTC) is used as a model of veterinary antibiotics to investigate the enzyme-immobilized microrobots for their removal capacities. The results demonstrate that the presence of laccase on the microrobot surfaces can enhance the removal of antibiotics via oxidation. This concept for immobilizing enzymes on self-propelled light-driven microrobots leads to the effective removal of the released antibiotics from water bodies with an environmentally friendly strategy.

The aim of this study was the development of antimicrobial polyvinylchloride (PVC) blends loaded with 0.1–10% (w/w) of the ILs 1-hexadecyl-3-methylimidazolium 1,3-dimethyl 5-sulfoisophthalate (HdmimDMSIP) and 1-octyloximethyl-3-methylimidazolium hexafluorophosphate (OOMmimPF6). The synthetized ILs were characterized by 1HNMR, MALDI-TOF, DSC and TGA. PVC/ILs films were obtained by solvent casting.Thermal and mechanical properties (tensile stress TS and elongation at break EB), morphology by SEM, surface wettability, antimicrobial activity, cytotoxicity and ILs release in sterile water from PVC/ILs film blends were determined. Results demonstrated that the presence of both ILs in PVC formulation slightly affected thermal and mechanical properties of blends. The loading of both ILs into PVC matrix made PVC/ILs films hydrophilic, especially at the highest concentration of HdmimDMSIP. The PVC/ILs blends displayed antibacterial activity up to ILs lowest concentrations (0.1–0.5%). The inhibition of Escherichia coli growth was lower than that showed toward Staphylococcus epidermidis. The addition of 10% ILs concentration resulted excessive as demonstrated by accumulation of ILs on film surfaces (SEM) and ILs high release from PVC/ILs blends during the first day of water immersion. Biocompatibility studies highlighted that the addition of low amounts of both ILs into PVC matrix is not cytotoxic for mouse fibroblast cells (L929), supporting their potential use for biomedical porposes.

Imidazolium-based ionic liquids (ILs) have interesting antimicrobial activity and their inclusion in a flexible film is ideal to take advantage of their properties in practical applications. Poly(ether-block-amide) (Pebax&reg, Rnew) films were prepared by solution casting, loading two synthetized ILs (1-hexadecyl-3-methylimidazolium dimethyl-5-sulfoisophthalate [Hdmim][DMSIP], IL1 and 1-octyloximethyl-3-methylimidazolium hexafluorophosphate [OOMmim][PF6], IL2) up to 5 wt.%. The ILs were characterized by 1H NMR and MALDI-TOF spectroscopy. The films were investigated for miscibility, morphology, wettability, spectral properties and gas transport. The films display a good thermal stability (&gt, 200 &deg, C). Differential scanning calorimetry (DSC) proves phase separation in the blends, that is consistent with FTIR analysis and with the island-like surface morphology observed in the micrographs. Gas permeability tests revealed that the IL-loaded films are dense and poreless, keeping the selectivity of the polymer matrix with a somewhat lessened permeability owing to the impermeable ILs crystals. The film antimicrobial activity, evaluated against Gram-negative and Gram-positive bacterial strains, was correlated to the structure of the incorporated ILs. The smaller IL2 salt did not modify the hydrophobic nature of the neat polymer and was readily released from the films. Instead, IL1, having a longer alkyl chain in the cation, provided a promising antimicrobial activity with a good combination of hydrophilicity, permeability and thermal stability.

The possibility to realize three dimensional (3D) graphene based architectures, able to strongly increase the high specific surface areas of this challenging material, while maintaining strong mechanical strengths and fast mass and electron transport kinetics, make them very promising in fields like sensing or catalysis [1]. In this contest, dopants like N can be introduced to induce a charge polarization in the carbon lattice, modifying its electronic properties and surface wettability, or to create anchoring sites for chemical reactions often used in organic chemistry to functionalized surfaces, enabling specific reactions and catalysis processes [2,3]. In this work we realize N-doped 3D graphene foams (GF) by chemical vapor deposition on Ni foams used as templates. We used CH4 and H2 as gaseous precursors and NH3 as N-doping source. The synthesis process is widely investigated in order to study the doping process and optimize the N type bonding mechanism. We found that the state in which N rearranges into the graphene lattice strongly depends on the stage of the Chemical Vapour (CVD) Deposition synthesis in which the NH3 is introduced in the reaction chamber. Moreover, if the N doping level is very high, it can affect the lateral growth of the graphene clusters, thus leading to micrometric triangular graphene domains. Morphological characterizations as a function of the CVD process conditions are modelled and their scenario is validated by means of ab-initio calibrated kinetic Monte Carlo simulations. The obtained data are of fundamental importance for a successful application of N-doped GF structures in sensing or catalysis field. REFERENCES [1]C. Backets et al. 2D Mater. 7 (2020) 022001 [2]H. Xu et al.Journal of Energy Chemistry 27 (2018) 146-160 [3]H. Wang et al. ACS Catal. 2 (2012) 781-79.

The influence of solvent used to prepare hybrid materials for photocatalytic applications formulated by cyclic bisphenol A/porphyrin copolyformal and graphene is here reported. To this purpose, the polymer is dissolved in different solvents [chloroform, tetrahydrofuran and dimethylformamide (DMF)] and used to impregnate via bath deposition 2D graphene. Depending on the nature of the solvent, polymer coats differently the graphene substrates producing peculiar SEM and AFM data. Microscopic and nanoscopic features of formulated materials were correlated with their photocatalytic activities by using methylene blue degradation test. Data collected under visible-light irradiation reveal as the best photodegradation performance was displayed by graphene coated with DMF copolyporphyrin solution. Graphic abstract: [Figure not available: see fulltext.].

The photo-oxidative degradation processes of bio-based PA11 nanocomposites containing montmorillonite (MMT) and the organo-modified Cloisite&reg, 30B were investigated to discriminate the influence of organo-modified components on the polymer durability. Indeed, despite the extensive studies reported, there are still ambiguous points to be clarified from the chemical point of view. To this aim, UV-aged materials were analyzed by Size Exclusion Chromatography (SEC), Inductively Coupled Plasma&ndash, Mass Spectrometry (ICP-MS) and Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). This enabled determining changes in both chemical structure and Molar Masses (MMs) induced by light, heat and oxygen exposure. The addition of organo-modified nanoclays strongly affected the PA11 light durability, triggering the macromolecular chains scission due to the typical &alpha, H, Norrish I and II mechanisms. However, the main contribution in boosting the photo-oxidative degradation is induced by iron impurities contained into the clays. Conversely, thermo-oxidation process performed at 215 &deg, C was unambiguously affected by the presence of the organo-modifiers, whose presence determined an enhancement of crosslinking reactions.

The incorporation of imidazolium ionic liquids (ILs) in flexible films is useful to take advantage of ILs remarkable properties [1] in many industrial applications. Poly(ether-block-amide) (Pebax®Rnew) membranes were prepared by controlled solvent evaporation loading, up to 5 wt.%, two ILs 1-octyloximethyl-3-methylimidazolium hexafluorophosphate [OOMmim][PF6] and 1-hexadecyl-3-methylimidazolium dimethyl-5-sulfoisophthalate [Hdmim][DMSIP] [2]. The ILs were synthetized and characterized by 1H NMR, MALDI-TOF spectroscopy, Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). The miscibility, morphology, wettability, gas transport, spectral and thermal properties of the obtained blends were investigated. TGA evidences a good thermal stability (>200 °C) for the membranes, while DSC reveals phase separation in the IL-loaded films, in accordance with the island-like surface morphology observed by Scanning Electron Microscopy (SEM) and with Fourier Transform Infrared (FTIR) analysis. Gas permeability tests shows that the films are defect-free, maintaining the original selectivity of the neat polymer with a reduction in the gas permeability due to the impermeable nature of the solid ILs crystals. The blend antimicrobial activity, tested against both Gram- (Escherichia coli, Pseudomonas fluorescens, Salmonella enterica) and Gram+ (Listeria monocytogenes and Bacillus subtilis) bacterial strains, depends on the chemical structure of the incorporated ILs. The smaller [OOMmim][PF6] only slightly lowers the hydrophobicity of the neat polymer and is readily released from the films. Instead, the [Hdmim][DMSIP], having a cation bearing a longer alkyl chain, induces a promising antimicrobial activity in the blends together with good hydrophilicity, permeability and thermal stability. Data on ILs release and biocompatibility/cytotoxicity suggest their application as antimicrobial coating on furniture for sterile environments/rooms, as filters for aerating systems and, at low concentrations of ILs (

The design of novel cryogels containing N‐methyl‐D‐glucamine (NMG) group was herein reported. The macroporous materials were prepared via sustainable and feasible cryopolymerization by using as co-monomers (4‐vinyl-benzyl)‐N‐methyl‐D‐glucamine (VbNMG) and 2-hydroxyethyl methacrylate (HEMA) at different percentages. Particularly, cryogel containing 100% of VbNMG (VbNMG-100) showed excellent ability in fast water uptake, removing arsenic (V) and chromium (VI) metal ions from it. Reusability up to six cycles was also demonstrated. The as-prepared materials were characterized by spectroscopic, thermal, and morphological analyses. The effect of initial oxyanions concentration, kinetic profiles, interfering anions (phosphate and sulphate) were investigated and adsorption/desorption studies were carried out. Equilibrium sorption results well fitted the Langmuir isotherm for both ions tested, showing a startling aptitude in arsenic (76.3 mg/g) as well as chromium (130.9 mg/g) sorption properties if compared with similar polymers as well as other materials. Exploiting its spongy nature, only 5 mins were needed to absorb contaminated medium releasing purified water by a simple squeezing. Most importantly, the sponge can be easily regenerated and reused again up to three times without the depletion of its efficiency.

A new concept in the formulation of hybrid nanostructured materials combining high quality graphene 3D supported by Nickel foam and polyporphyrins for visible light photocatalytic application is here reported. Our innovative approach involves the development of a freestanding device able to: i) offer a high surface area to bind the photosensitizers by π-π interactions, and ii) enhance stability and photocatalytic efficiency by using cyclic porphyrin polymers. For these purposes, homo- and co-polymerization reactions by using different porphyrin (free or zinc complexed) monomers were performed. The microscopic structures and morphology of graphene polymer nanocomposites were investigated by using Scanning Electron Microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Atomic Force Microscopy (AFM). Finally, photocatalytic activity under visible light irradiation of the obtained nanocomposites was tested, by using methylene blue (MB) as organic pollutant. The obtained data suggested that hindered cyclic polymeric structures stacked on graphene surface by non-covalent interactions, restrict the formation of non photoactive aggregates and, as a consequence, induce an enhancement of photocatalytic activity. Remarkably, our systems show a degradation efficiency in the visible-light range much higher than other similar devices containing nanoporphyrin units reported in literature.

Due to rapid population growth and intensification of agricultural and industrial activities, a diverse array of hazardous pollutants is progressively entered in the aquatic system. Particularly, persistent organic contaminants such as pesticides, solvents, dyes, detergents and industrial chemicals, constitute a pressing ecological problem that poses a great threat to human health [1]. An eco-friendly and definitive process to eliminate contaminants from water is concerned on their complete mineralization by using photocatalytic approach [2], followed by an efficient and easily catalyst separation at the end of the process. In light of this, we have formulated a novel multifunctional super-adsorbent sponge based on poly-2-hydroxyethyl methacrylate/graphene oxide (pHEMA@GO) composite developed by a cryo-polymerization in water [3]. In addition, taking advantages by the hydroxyl pendant groups present on both HEMA and GO moieties, our strategy involves the use of the sponge as a platform to link covalently ZnO by using Atomic Layer Deposition (ALD). This step can provide them the ability to degrade pollutants via photocatalytic process after the adsorption.

A novel hybrid photoactive material based on graphene foam (G) coupled with porphyrin-based polymers (Porph rings) was formulated by using a time-saving procedure to remove nickel from the final device. Specifically, Porph rings were spin coated onto the G platform with the double function of a visible-light photocatalyst and protective agent during nickel etching. The characterization of G-Porph rings was assessed by Scanning Electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL). The novel material showed photocatalytic ability in degrading different classes of pollutants such as the herbicide 2,4 dichlorophenoxyacetic acid (2,4-D), polyethylene glycol (PEG) as an ingredient of care and health products, and also the methylene blue (MB) dye. UV-Vis spectroscopy, total organic carbon (TOC) and soft mass spectrometry techniques were used to monitor the photocatalytic process. The best performance in terms of photocatalytic efficiency was exhibited versus PEG and MB degradation. Furthermore, to determine the individual contribution of Reactive Oxygen Species (ROS) produced, free radical and hole scavenging tests were also carried out. Finally, a detailed map of the photocatalytic degradation mechanisms was proposed, reporting also the calculation of Porph rings' Highest Occupied Molecular Orbital (HOMO) and Lowest Occupied Molecular Orbital (LUMO) energy level values.

Introduction/Purpose Novel multifunctional sponges based on poly-2-hydroxyethyl methacrylate (pHEMA) or polymethacrylic acid (pMAA) filled with Graphene Oxide (GO) were formulated with the aim to effectively remove organic pollutants from water. Our strategy involves also the deposition of ZnO on substrates to form a covalent linkage with the OH or COOH polymer pendant groups. Indeed, ZnO nanostructuration could provide the ability to degrade pollutants via photocatalytic process after the adsorption step. Methods The sponges were obtained by criopolymerization of monomers (HEMA, MAA) and the crosslinking agent in water solution (molar ratio of 6:1 and 1% w/w initiatior, of the total monomer), by adding GO as filler at -16 °C. The grafting of ZnO was performed by Atomic Layer Deposition at 80 °C. Morphological, thermal and mechanical investigations were carried out by using SEM, TEM, FTIR X-Ray analyses and TGA. Adsorption kinetics, porosity, equilibrium swelling degree and the photodegradation capability of cryogels were also evaluated [1]. Results The ZnO nanostructured polymeric sponges obtained as described above, showed high polymerization yields (80-85%), good mechanical and swelling properties as well as adsorption capability versus Methylene Blue (MB) and Atrazine [1]. To verify the efficacy of the regeneration process, adsorption of MB followed by its photocatalytic degradation was carried out. Three adsorptions were performed; between them, all samples were irradiated by UV lamps to regenerate the material via the photocatalytic action of ZnO. The adsorption results collected for each cycle (Fig. 1) showed as the percentage of adsorbed MB remains kostant for samples containing ZnO. Conclusions Hybrid sponges based on acrylate polymers and GO able to adsorb organic pollutant from water were formulated. MB degradation test showed as sponges containing ZnO have acquired photocatalytic properties. In particular, the recyclability tests revealed that pHEMA/ZnO materials can be easily regenerated and reused, explicating an effective remediation action versus organic pollutants. Selected references Ussia et al. ACS Appl. Mater. Interfaces, 10, 46, 40100-40110 (2018)

Ferrocenyl(benzyl) imidazole (FcIm) and two related methyl-imidazolium salts (FcMImI and FcMImPF) were synthesized for their incorporation into plasticized PVC by solvent casting technique. The obtained materials were investigated for their thermal stability and, compared to pure polymer, films containing ionic ferrocene derivatives in 0.5% w/w loading were found slightly more stable. The pure ferrocene compounds showed antibacterial activity against Staphylococcus epidermis, but not against Escherichia coli, with a maximum for FcMImPF salt. After incorporation into PVC polymer, antibacterial activity against S. epidermis was observed (by disk diffusion test) only for PVC/FcMImPF (5% w/w) film, from which a release of 14.6% of the ferrocenilimidazolium cation in aqueous medium was measured after 24 hr.

The design of new hybrid nanocomposites based on poly(2-hydroxyethylmethacrylate) (pHEMA) graphene oxide (GO) cryosponges, wherein ZnO nanolayers have been deposited to induce photocatalytic properties, is reported here. Atomic layer deposition at low temperature is specifically selected as the deposition technique to stably anchor ZnO molecules to the pendant polymer OH groups. Furthermore, to boost the pHEMA cryogel adsorption capability versus organic dyes, GO is added during the synthetic procedure. The morphology, the crystallinity, and the chemical composition of the samples are deeply investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction analyses, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Swelling properties, mechanical performance, and adsorption kinetics models of the hybrid materials are also evaluated. Finally, the adsorption and photocatalytic performance are tested and compared for all of the samples using methylene blue as a dye. Particularly, the adsorption efficiency of ZnO/pHEMA and ZnO/pHEMA-GO nanocomposites, as well as their in situ regeneration via photocatalysis, renders such devices very appealing for advanced wastewater treatment technology.

The formulation of cost-effectiveness sustainable materials is extensively growing and becoming an attractive approach for both industrial and academic fields. In this context, the bio-based aliphatic polyamide 11 (PA11) has acquired significant interest as environmentally friendly thermoplastic option. In addition, its formulation with selected natural antioxidant and/or reinforced compounds through green processing methods, might improve physical and mechanical properties without sacrificing the intrinsic bio-based nature of the matrix. In this work, we have investigated and compared the photo oxidative degradation processes occurring on PA11 composites based on thymol and halloysite nano tubes prepared by using ball-milling method. In particular, halloysite nanotubes were used as green nano-container of a natural antioxidant molecule, and reinforced nano-filler as well. Molecular and structural information of photo-exposed samples were obtained by using size exclusion chromatography (SEC) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Thermal and mechanical properties were also tested as well as thymol release. Data collected confirmed that PA11 filled with HNTs-Thymol nano-hybrid showed superior durability performance if compared to both pure PA11 and PA11 blend realized by simply adding thymol and HNTs to polymer matrix. Furthermore, we found that HNTs and thymol combined in the nano-hydrid form exhibited an active and synergic role to achieve a major photo stabilization of PA11 biocomposite, without sacrificing its mechanical properties. (C) 2018 Elsevier Ltd. All rights reserved.

I criogeli sono materiali polimerici macroporosi ottenuti tramite un processo di polimerizzazione ad una temperatura inferiore al punto di congelamento del solvente utilizzato per la dissoluzione dei monomeri. In queste condizioni la formazione del polimero avviene attorno ai cristalliti del solvente congelato. Dopo lo scongelamento del sistema si ottiene un materiale spugnoso in cui sono presenti pori interconnessi che ricalcano la struttura dei cristalli di solvente presenti durante la polimerizza-zione [1]. Le dimensioni dei pori dipendono essen-zialmente dalla velocità di cristallizzazione del solvente, che è un parametro strettamente dipen-dente dalla temperatura in cui avviene la polimeriz-zazione. La presenza di pori di dimensioni medie dell'ordine delle decine di micrometri conferisce a tali materiali alcune proprietà chimico-fisiche tali da differenziarli in maniera sostanziale da normali idrogel, quali una elevata velocità di assorbimento e scambio di fluidi, elevata flessibilit? e possibilità di compressione con rilascio dei fluidi assorbiti. Tali proprietà possono venire sfruttate in maniera egregia soprattutto in applicazioni in cui sono necessarie elevate capacità adsorbenti unite ad un rapido raggiungimento delle condizioni di equili-brio [2]. Una applicazione in cui le interessanti caratteristiche dei criogel possono venire adegua-tamente sfruttate è quella della purificazione e potabilizzazione delle acque [3]. A tal proposito abbiamo preparato criogel compositi a base di poli-idrossietilmetacrilato (pHEMA) contenente grafene ossido (GO) per potenziare le capacità adsorbenti del materiale nei confronti di inquinanti di tipo organico [4]. Infine, tramite un processo di Atomic Layer Deposition (ALD) abbiamo aggiunto ZnO nanostrutturato ai materiali sintetizzati, confe-rendogli l'abilità di poter degradare per via foto-chimica gli inquinanti adsorbiti [5]. Test di adsor-bimento e successiva decomposizione di blu di metilene (MB) utilizzato come modello di inquinan-te organico presente in soluzione acquosa, hanno mostrato le eccellenti performance di cattura e foto-decomposizione proprie di questi materiali, nonché la possibilità di essere riciclati ed usati per cicli multipli di cattura-fotodecomposizione di inquinanti organici dalle acque.

The design of graphene-based (G) hybrid nano-materials for photocatalytic applications is one of the most promising routes in the field of water remediation1. Indeed, the combination of G with photoactive materials aims to strongly improve the photocatalytic performance of the formulated systems by boosting the separation and transfer of photo-generated charges, which constitutes a critical step in photocatalytic reactions. As it turns out, organic photosensitizers, which have an excellent visible-light (VL) absorption, coupled with the charge transfer properties of G-based materi-als (graphene, graphene oxide and reduced gra-phene oxide) represent cutting-edge water treat-ment technology. Moreover, the low cost, eco-friendliness, flexibility, and versatility of the mo-lecular design of these basic organic molecules constitute appealing features, both environmental-ly and economically. In this view, a freestanding hybrid nanocomposites by using high quality graphene 3D supported by Nickel foam and photoactive macromolecules was realized. The novelty of our approach consists in exploiting extensive non- covalent interactions between the high surface area of G co-catalyst by using a homo and copolycyclic polyporphyrins with and metal free (CPPrs). The unusual choice of CPPrs as photoactive sites is based on two assump-tions: i) their hindered conformational geometries might significantly avoid formation of agglomer-ates of single porphyrin units, that act the rapid quenching of excited state; ii) if compared to isolate photo-active molecules, polymers possess improved mechanical properties, being able to coat and protect the co-catalyst surface. Moreo-ver, our structure shows very high avalaible sur-face thanks to its foam structure, with clear ad-vantages in its PC performances. This new concept of GNPs formulation might avoid the shielding effect as well as the radical scavenger activity, maximizing the charge transfer process during photo-catalysis. The PCE of these GNPs were tested and compared to G/Pr units by photo-degrading MB dye in water under VL irradia-tion 2.

The design of new hybrid nanocomposites based on poly (2-hydroxyethylmethacrylate) (pHEMA) graphene oxide (GO) cryo-sponges, wherein ZnO nanolayers have been deposited to impart them photocatalytic properties, is here reported. Atomic layer deposition (ALD) at low temperature is specifically selected as deposition technique to stable anchor ZnO molecules to the pendant polymer OH groups. Furthermore, to boost the PHEMA cryo-gel adsorption capability versus organic dyes, GO is added during the synthetic procedure. The morphology, the crystallinity, and the chemical composition of the samples were deeply investigated by scanning electron microscopy (SEM), X-ray diffraction analyses (XRD), Fourier transform infrared spectroscopy (FTIR) as well as thermogravimetric analysis (TGA). Swelling properties and adsorption kinetics models of the hybrid materials were also evaluated. Finally, the adsorption and photocatalytic performance were tested and compared for all samples by using methylene blue (MB) as simulant dye. Particularly, the adsorption efficiency of ZnO PHEMA and ZnO PHEMA GO nanocomposites, as well as they in situ regeneration via photocatalysis, render such devices very appealing for advanced wastewater treatment technology.

The ferrocenyl analogue of clotrimazole, in which the metallocene fragment replaces one of the phenyl rings in the triphenylmethane system, and a related isomer were prepared through the direct substitution of a methoxygroup in the α-position to ferrocene with imidazole in the key step. The obtained ferrocenyl derivatives were spectroscopically characterized and in a preliminary assay for bioactivity their cell growth inhibitory activity on two different human cancer cell lines was evaluated. In comparison with the parent drug the ferrocene analogues displayed about two-fold increase of cytotoxicity on HT29 colorectal cancer cells, whereas comparable activity was displayed against MCF-7 breast cancer cell line.

The main goal of the work was the optimization of the procedure for the production of: -Active multifunctional nanocomposites based on polymer nanofibers with ZnO nanoroads growth by chemical Bath Deposition on the surface of undoped and Zn(Ac)2 doped polyethersulfone (PES) electrospun fibres; -Silver nanoparticles as nanofiller to obtain electrospun membrane with water purification and antifouling properties, -MWCNTs as nanofiller to give electrospun nanofiber with mechanical reinforced properties. The hybrid structures were characterized by SEM, EDX analysis and UV-vis spectroscopy. Zn(Ac)2 doped PES fibrous mats were obtained by roll-to-roll electrospinning of polymer solutions doped with zinc acetate. The presence of Zn acetate contributes to thermally stabilize the polymeric composite, due to formation of ZnO during thermal treatments. Brush-like ZnO nanorods were grown on the obtained sub-micrometer PES fibers by Chemical Bath Deposition to obtain highly nanostructured surfaces with a high level of crystallinity. These hierarchical mats are water resistant and photocatalytic actives. It was optimized the pre-spinning solution for the production of PES /Ag nanoparticles fibers using the Localized Surface Plasmon Resonance (LSPR) phenomenon of the silver nanoparticles, finding the concentration of PVP necessary for stabilize the silver ions reduction with shortest time. SEM and EDX characterizations confirmed the presence of silver nanoparticles into PES fibers. The membranes obtained are suitable for the production of multifunctional composites based on epoxy resin by "dissolution in situ" process. Fibers with MWCNT as nanofiller showed bead-on string morphology (increasing the percentage of MWCNTs, the bead dimensions also increase), whereas fibers without MWCNTs are bead-free.