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Plasma-catalysis has been recognized as a promising method to decompose hazardous volatile organic compounds (VOCs) since many years ago. To understand the fundamental mechanisms of VOCs decomposition by plasma-catalysis systems, both experimental and modeling studies have been extensively carried out. However, literature on summarized modeling methodologies is still scarce. In this short review, we therefore present a comprehensive overview of modeling methodologies ranging from microscopic to macroscopic modeling in plasma-catalysis for VOCs decomposition. The modeling methods of VOCs decomposition by plasma and plasma-catalysis are classified and summarized. The roles of plasma and plasma-catalyst interactions in VOCs decomposition are also critically examined. Taking the current advances in understanding the decomposition mechanisms of VOCs into account, we finally provide our perspectives for future research directions. This short review aims to stimulate the further development of plasma-catalysis for VOCs decomposition in both fundamental studies and practical applications with advanced modeling methods., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

It is urgent to control the emission of volatile organic compounds (VOCs) due to their harmful effects on the environment and human health. A hybrid system integrating non-thermal-plasma and catalysis is regarded as one of the most promising technologies for VOCs removal due to their high VOCs removal efficiency, product selectivity and energy efficiency. This review systematically documents the main findings and improvements of VOCs removal using plasma-catalysis technology in recent 10 years. To better understand the fundamental relation between different aspects of this research field, this review mainly addresses the catalyst development, key influential factors, generation of by-products and reaction mechanism of VOCs decomposition in the plasma-catalysis process. Also, a comparison of the performance in various VOCs removal processes is provided. Particular emphasis is given to the importance of the selected catalyst and the synergy of plasma and catalyst in the VOCs removal in the hybrid system, which can be used as a reference point for future studies in this field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Coronavirus disease 2019 (COVID-19) is largely threatening global public health, social stability, and economy. Efforts of the scientific community are turning to this global crisis and should present future preventative measures. With recent trends in polymer science that use plasma to activate and enhance the functionalities of polymer surfaces by surface etching, surface grafting, coating and activation combined with recent advances in understanding polymer-virus interactions at the nanoscale, it is promising to employ advanced plasma processing for smart antiviral applications. This trend article highlights the innovative and emerging directions and approaches in plasma-based surface engineering to create antiviral polymers. After introducing the unique features of plasma processing of polymers, novel plasma strategies that can be applied to engineer polymers with antiviral properties are presented and critically evaluated. The challenges and future perspectives of exploiting the unique plasma-specific effects to engineer smart polymers with virus-capture, virus-detection, virus-repelling, and/or virus-inactivation functionalities for biomedical applications are analysed and discussed., Competing Interests: The authors declare no competing interests., (© 2021 The Authors. Published by Elsevier B.V.)

In this paper, the photocatalytic activity of plasma-functionalized Cu-doped TiO 2 nanoparticles (NPs) and the oxidization process of atmospheric pressure plasma jet were combined for the degradation of reactive red-198 (RR-198) in aqueous solution. The first part of the study was thus devoted to subject Cu-‒TiO 2 NPs synthetized by the sol-gel method to various plasma treatments operating in air, argon, oxygen and nitrogen to improve their degradation efficiency. The physicochemical properties of the NPs were then assessed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) measurements. XRD results indicated the predominant presence of the anatase phase which is the most photoactive form of TiO 2 . The XPS analysis revealed that the different plasma treatments triggered the formation of oxygen vacancies, Ti 3+ oxidation state and Cu 2+ oxidation state on the surface of Cu-‒TiO 2 NPs. These changes, known to prevent the recombination of electron-hole pair, have led to a reduction in the bandgap that was more pronounced for the N 2 plasma-treated NPs. The second part of the paper explored the actual degradation of RR-198 in aqueous solution by an Ar plasma treatment alone or combined with the plasma pre-treated Cu-‒TiO 2 NPs. Optical emission spectroscopy (OES) and spectrophotometric analyses showed that the synergetic effect of Ar plasma and N 2 plasma-treated NPs produced the highest concentration of OH • radicals and H 2 O 2 species which led to the highest RR-198 degradation efficiency. This was further confirmed by pH, electrical conductivity and total organic carbon (TOC) removal measurements. The degradation of RR-198 was determined using UV-Vis spectroscopy and high-performance liquid chromatography (HPLC). Overall, it can be concluded that plasma-assisted processes illustrated by a combination of a direct plasma treatment with plasma-functionalized Cu-‒TiO 2 NPs can be used in various textile and pharmaceutical industries as a highly effective treatment of their effluents before discharging., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Antibacterial coating is an important strategy preventing bacterial colonization and biofilm formation. One-step synthesis of nanocapsule-containing antibacterial coatings with controlled release of Ag + ions was achieved in the current work by aerosol-assisted atmospheric pressure plasma deposition. The experimental parameters of deposition including the discharge power, silver nitrate concentration, aerosol flow rate, continuous and pulsed mode of operation were studied in order to analyze their effects on surface morphology and chemical composition of the coating. Formation of nanocapsules embedded in the polymeric coating was observed. A core-shell structure was found for nanocapsule with silver in the core and polymer in the shell. Antibacterial coatings on polyethylene terephthalate film were studied in terms of Ag + ion release, antibacterial properties against Escherichia coli and Staphylococcus aureus, and cytotoxicity with murine fibroblasts. Two-phase release kinetics of Ag + ions was observed as initially a short-term burst release followed by a long-term slow release. It was revealed that high antibacterial efficiency of the coatings deposited on polyethylene terephthalate films can be coupled with low cytotoxicity. These biocompatible antibacterial coatings are very promising in different fields including biological applications., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Infection associated with titanium based implants remains the most serious problem in implant surgery hence it is important to find optimal strategies to prevent infections. In the present study, we investigated the surface properties, antibacterial activity and biocompatibility of nanocomposite coatings based on an amorphous hydrocarbon (a-C:H) film containing copper nanoparticles (CuNPs) deposited on Ti discs via a gas aggregation cluster source. Three different Cu/a-C:H coatings with approximately the same amount of embedded CuNPs with and without barrier a-C:H layer were fabricated. The obtained results revealed that different structures of the produced coatings have significantly different release rates of Cu ions from the coatings into the aqueous media. This subsequently influences the antibacterial efficiency and osteoblast cell viability of the treated coatings. Coatings with the highest number of CuNPs resulted in excellent antibacterial activity exhibiting approximately 4 log reduction of E.coli and S.aureus after 24 h incubation. The cytotoxicity study revealed that after 7 day cell seeding, even the coating with the highest Cu at.% (4 at.%) showed a cell viability of ̴90%. Consequently, the coating, formed with a properly tailored number of CuNPs and a-C:H barrier thickness offer a strong antibacterial effect without any harm to osteoblast cells., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A dielectric barrier discharge reactor packed with both Hopcalite & glass beads has been investigated for the total oxidation of toluene adsorbed on Hopcalite. The catalytic activity and selectivity through the possible formation of by-products during the NTP discharge for the abatement of irreversibly adsorbed toluene have been investigated by FT-IR and mass spectrometer. The regeneration of the used Hopcalite by NTP discharge has been established by (i) determining the amount of toluene adsorbed on NTP regenerated Hopcalite, (ii) investigating the catalytic activity of NTP regenerated Hopcalite and (iii) comparing the bulk and surface properties of the fresh calcined and NTP regenerated Hopcalite. The ratio of amount of irreversibly adsorbed toluene to that of the total amount of adsorbed toluene adsorbed is similar for the fresh calcined and NTP (I) regenerated Hopcalite. The catalytic activity of the NTP (I) regenerated Hopcalite is slightly enhanced when compared to that of the fresh calcined Hopcalite. Although the first NTP treatment induces partial transformation of Hopcalite into Mn 3 O 4 with no detected related CuO x and reduces specific surface area by a factor of 2, the toluene adsorption capacity remains less affected. A plausible reaction scheme for toluene decomposition in Hopcalite PBDBD reactor is proposed., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The removal of dilute trichloroethylene (TCE) in moist air by post-plasma catalysis (PPC) using Cu-Mn mixed oxides heated at 150 °C was investigated. Cu-Mn mixed oxides were prepared by redox- and co-precipitation method. In comparison to the catalytic oxidation and non-thermal plasma (NTP) process, PPC was found to be the best process to convert TCE into CO 2 , in particular when Cu-Mn oxide was synthetized by redox precipitation method. The highest TCE conversion efficiency of more than 80% was obtained at the energy density of 60 J.L -1 using the catalyst prepared by redox-precipitation process in PPC configuration. The performance of Cu-Mn oxide prepared by redox-precipitation method did not show increase in TCE conversion with energy density which is attributed to the changes on the catalyst surface (such as reduction in S BET , chlorine poisoning and Mn enrichment). Although, Cu-Mn oxide prepared by co-precipitation method showed a lower TCE conversion, it exhibited a better stability in the PPC process for TCE abatement., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The bioactivity of synthetic bone implants is highly impacted by their surface topography, especially by the presence of micro-patterns likely to generate cells growth guidance. In this study, laser machining technology was employed in order to produce controlled regular micro-patterns on dense calcium phosphate surfaces, without any contamination. The choice of the source was directed towards a femtosecond pulsed laser in order to limit the thermal impact of such a process and thus to avoid the unwanted phase transformations potentially induced by the temperature elevation. Beta tricalcium phosphate substrates with perfectly controlled micro-patterning and without any secondary phase were obtained by optimization of the process parameters (laser power, scanning speed, pulse frequency). The microstructural characteristics were investigated by microscopy (optical, confocal, scanning electron) and the phase identification was performed by X-ray diffraction. This work allowed highlighting the effects of the process parameters on the patterning. The high benefits of the laser treatment on wettability were shown by contact angle assays. Finally, the influence of surface micro-patterning on cell behavior was highlighted in vitro. This technique seems to provide an interesting alternative to conventional surface treatments of calcium phosphates., (Copyright © 2018 Elsevier B.V. All rights reserved.)

This work describes the development of antifouling functional coatings on the surface of low density polyethylene (LDPE) films by means of atmospheric pressure non-thermal plasma (APNTP) assisted copolymerization using a mixture of acrylic acid and poly (ethylene glycol). The aim of the study was to investigate the antifouling properties of the plasma copolymerized LDPE films and the same was carried out as a function of deposition time with fixed applied potential of 14 kV. In a second stage, the plasma copolymerized LDPE films were functionalized with chitosan (CHT) to further enhance its antifouling properties. The surface hydrophilicity, structural, topographical and chemistry of the plasma copolymerized LDPE films were examined by contact angle (CA), X-ray diffraction (XRD), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Coating stability was also studied in detail over a storage time of 15 days by storing in water and air. The antifouling properties of the plasma copolymerized LDPE films were examined via protein adsorption and platelet adhesion studies. CA study showed significant changes in surface wettability after the coating process. XPS and FTIR analysis proved the presence of a dense multifunctional coating and an efficient immobilization of CHT. Substantial amendments in surface topography were observed, positively enhancing the overall surface hydrophilicity. Finally, in-vitro analysis showed excellent antifouling behavior of the surface modified LDPE films., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The total oxidation of trichloroethylene (TCE) in air at low relative humidity (RH=10%) in the presence of CO2 (520ppmv) was investigated in function of energy density using an atmospheric pressure negative DC luminescent glow discharge combined with a cryptomelane catalyst positioned downstream of the plasma reactor at a temperature of 150°C. When using Non-Thermal Plasma (NTP) alone, it is found a low COx (x=1-2) yield in agreement with the detection of gaseous polychlorinated by-products in the outlet stream as well as ozone which is an harmful pollutant. Introduction of cryptomelane enhanced trichloroethylene removal, totally inhibited plasma ozone formation and increased significantly the COx yield. The improved performances of the hybrid system were mainly ascribed to the total destruction of plasma generated ozone on cryptomelane surface to produce active oxygen species. Consequently these active oxygen species greatly enhanced the abatement of the plasma non-reacted TCE and completely destroyed the hazardous plasma generated polychlorinated intermediates. The facile redox of Mn species associated with oxygen vacancies and mobility as well as the textural properties of the catalyst might also contribute as a whole to the efficiency of the process., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The superior bulk properties (corrosion resistance, high strength to weight ratio, relatively low cost and easy processing) of hydrocarbon based polymers such as polypropylene (PP) have contributed significantly to the development of new biomedical applications such as artificial organs and cell scaffolds. However, low cell affinity is one of the main draw backs for PP due to its poor surface properties. In tissue engineering, physico-chemical surface properties such as hydrophilicity, polar functional groups, surface charge and morphology play a crucial role to enrich the cell proliferation and adhesion. In this present investigation TiOx based biocompatible coatings were developed on the surface of PP films via DC excited glow discharge plasma, using TiCl4/Ar+O2 gas mixture as a precursor. Various TiOx-based coatings are deposited on the surface of PP films as a function of discharge power. The changes in hydrophilicity of the TiOx/PP film surfaces were studied using contact angle analysis and surface energy calculations by Fowke's approximation. X-ray photo-electron spectroscopy (XPS) was used to investigate the surface chemical composition of TiOx/PP films. The surface morphology of the obtained TiOx/PP films was investigated by scanning electron and transmission electron microscopy (SEM &TEM). Moreover, the surface topography of the material was analyzed by atomic force microscopy (AFM). The cytocompatibility of the TiOx/PP films was investigated via in vitro analysis (cell viability, adhesion and cytotoxicity) using NIH3T3 (mouse embryonic fibroblast) cells. Furthermore the antibacterial activities of TiOx/PP films were also evaluated against two distinct bacterial models namely Gram positive Staphylococcus aureus (S.aureus) and Gram negative Escherichia coli DH5α. (E.coli) bacteria. XPS results clearly indicate the successful incorporation of TiOx and oxygen containing polar functional groups on the surface of plasma treated PP films. Moreover the surface of modified PP films exhibited nano structured morphology, as confirmed by SEM, TEM and AFM. The physico-chemical changes have improved the hydrophilicity of the PP films. The in-vitro analysis clearly confirms that the TiOx coated PP films performs as good as the standard tissue culture plates and also are unlikely to impact the bacterial cell viability., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This paper reviews recent achievements and the current status of non-thermal plasma (NTP) technology for the abatement of volatile organic compounds (VOCs). Many reactor configurations have been developed to generate a NTP at atmospheric pressure. Therefore in this review article, the principles of generating NTPs are outlined. Further on, this paper is divided in two equally important parts: plasma-alone and plasma-catalytic systems. Combination of NTP with heterogeneous catalysis has attracted increased attention in order to overcome the weaknesses of plasma-alone systems. An overview is given of the present understanding of the mechanisms involved in plasma-catalytic processes. In both parts (plasma-alone systems and plasma-catalysis), literature on the abatement of VOCs is reviewed in close detail. Special attention is given to the influence of critical process parameters on the removal process., (Copyright © 2011 Elsevier B.V. All rights reserved.)