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Nitrogen plasma emission spectrum in the 630–1830 nm range. Different atomic transitions are distinguished by rectangles (300 W, 0.1 Torr, 10 sccm).
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UV–visible and infrared (IR) emission spectroscopy measurements were performed in a N2 microwave discharge at pressures between 0.1 and 3 Torr and powers of 200 and 300 W. Although emission spectroscopy in the IR region has rarely been investigated, this technique has nevertheless provided numerous key data. The plasma temperature as a function of...
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... of the N 2 1st positive system that are not observable through classical UV–VIS emission spectroscopy. The detector used during each experiment was a thermoelectrically cooled indium arsenide semiconductor (InAs) which is sensitive in the range 3000–14 000 cm − 1 (710–3300 nm). One hundred interferograms were routinely co-added and Fourier-transformed, thereby enabling us to record spectra with an acceptable signal-to-noise ratio and reasonable acquisition time. Figure 2 shows the typical IR emission spectrum of the N 2 microwave discharge. The observed IR spectra consisted mostly of N 2 1st positive transitions. In addition, the spectra recorded at a low gas pressure ( p 1 Torr) enabled us to visualize various N I atomic transitions. In the illustrated spectrum, the IR features were related to different vibrational transitions originating from the 1st positive system of N 2 (B 3 g → A 3 + u ) . Table 1 lists the vibrational transitions ( v = v − v = − 3 , − 2 , 0 , 1 , 2 , 3 ) of N 2 in the IR region as well as their corresponding wavelengths [30]. It should be emphasized here that only a few results have been published on the first vibrational levels of the N 2 1st positive system (1050 nm for the N 2 (B, 0– A, 0 ) transition), as these transitions for λ > 900 nm occur in the IR region and are therefore very difficult to detect with standard UV–VIS optical spectrometry. This study is therefore among the first to retrieve plasma physicochemical data from the first vibrational transitions of the 1st positive system of N 2 . Also of interest is that emission spectroscopy in the IR region made it possible to detect the nitrogen atomic transition. Indeed, no intense atomic transition was detectable in the UV– VIS spectral region in the pressure and microwave power ranges selected for this study. However, atomic emission lines can be easily observed in the near-IR region. The most intense lines are highlighted by rectangles in figure 2, and one of these, located at 10 646 cm − 1 (939.3 nm), is ...
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... of the N 2 1st positive system that are not observable through classical UV–VIS emission spectroscopy. The detector used during each experiment was a thermoelectrically cooled indium arsenide semiconductor (InAs) which is sensitive in the range 3000–14 000 cm − 1 (710–3300 nm). One hundred interferograms were routinely co-added and Fourier-transformed, thereby enabling us to record spectra with an acceptable signal-to-noise ratio and reasonable acquisition time. Figure 2 shows the typical IR emission spectrum of the N 2 microwave discharge. The observed IR spectra consisted mostly of N 2 1st positive transitions. In addition, the spectra recorded at a low gas pressure ( p 1 Torr) enabled us to visualize various N I atomic transitions. In the illustrated spectrum, the IR features were related to different vibrational transitions originating from the 1st positive system of N 2 (B 3 g → A 3 + u ) . Table 1 lists the vibrational transitions ( v = v − v = − 3 , − 2 , 0 , 1 , 2 , 3 ) of N 2 in the IR region as well as their corresponding wavelengths [30]. It should be emphasized here that only a few results have been published on the first vibrational levels of the N 2 1st positive system (1050 nm for the N 2 (B, 0– A, 0 ) transition), as these transitions for λ > 900 nm occur in the IR region and are therefore very difficult to detect with standard UV–VIS optical spectrometry. This study is therefore among the first to retrieve plasma physicochemical data from the first vibrational transitions of the 1st positive system of N 2 . Also of interest is that emission spectroscopy in the IR region made it possible to detect the nitrogen atomic transition. Indeed, no intense atomic transition was detectable in the UV– VIS spectral region in the pressure and microwave power ranges selected for this study. However, atomic emission lines can be easily observed in the near-IR region. The most intense lines are highlighted by rectangles in figure 2, and one of these, located at 10 646 cm − 1 (939.3 nm), is ...
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... 2 (B) N 2 (A) + hυ( 1st pos ) k 2 . 4 10 s [42] (g) Theoretical models have shown that the main population channels of the B state in most low-pressure N 2 discharges are electron impact excitations from the molecule ground X state and the A metastable state (reaction (a)) [47, 48]. For example, using the plasma kinetic model developed by De Benedictis et al [48], in a 0.1 Torr-pulsed N 2 discharge ( t on = t off = 5 × 10 − 3 s) with a gas temperature of 350 K, the production rate of the B state by electron impact in the discharge counts for ∼ 55% from the X state and ∼ 34% from the A state. Other minor processes are the associative excitation (reaction (b): 3%), the pooling reaction (reaction (c): 0.7%) and the radiative decay from the C state (reaction (e): 7%). Reactions (b) and (c) have to be taken into account at high pressures ( P > 0 . 1 Torr) when enough electron density and energy are not there to dominate the excitation of N 2 (B, v ) . The N-atom recombination reaction (d) is dominant in flowing afterglows [15] at a higher N 2 gas pressure (more than several torrs) and room gas temperature. It was thus disregarded under the plasma conditions of our experiment. Reactions (f) and (g) are the loss terms of the N 2 (B) states by radiative emission and quenching, respectively. To investigate the primary mechanism for the B 3 g population, we used experimental IR-region plasma characterization with v = − 2 (see figure 2) using four different transitions (1299.7 nm, 1357.2 nm, 1420.1 nm and 1489.5 nm). For this rather narrow spectral region, the spectral response of the FTIR spectrometer was fairly flat and as each vibrational transition overlapped with several rotational transitions, the aforementioned peaks were curve-fitted, and their total surface intensity, rather than peak height intensity, was measured (see figure 9). Taking into account reaction (1a) and assuming a Treanor distribution for N 2 (X, v) vibrational levels for which the distribution f (v) was calculated from the following analytical equation ...
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... The identification of su mation on the plasma/surface reactions that are taking place obtained during the plasma treatment with and without La the plasma reactor are shown in Figure 4. The emission plasma treatment without Lavandin Grosso flowers inside ferent characteristic emission bands associated with nitrox gion 225-283 nm, OH radicals (OH•: 308.9 nm, 287 nm) [4 ond positive system, N2 SPS) in the region 297-430 nm, nitro FNS) in the region 390-490 nm and nitrogen first positive 660-760 nm [49][50][51][52], and atomic oxygen lines at 715 and 77 OH radicals can be attributed to the water-rich atmosphe maining peaks associated with nitrogen and oxygen reactiv ence of air in the reactor environment. The spectrum collec ment with Lavandin Grosso flowers inside the reactor sh peak's intensity attributed to the smaller effective area of the of the Lavandin Grosso flowers on it. ...
... The UV-vis emission spectra obtained during the plasma treatment with and without Lavandin Grosso flowers inside the plasma reactor are shown in Figure 4. The emission spectra recorded during the plasma treatment without Lavandin Grosso flowers inside the plasma reactor show different characteristic emission bands associated with nitroxide molecules (NO Υ ) in the region 225-283 nm, OH radicals (OH•: 308.9 nm, 287 nm) [47,48], nitrogen molecules (second positive system, N 2 SPS) in the region 297-430 nm, nitrogen first negative system (N + 2 FNS) in the region 390-490 nm and nitrogen first positive system (N 2 FPS) in the region 660-760 nm [49][50][51][52], and atomic oxygen lines at 715 and 777 nm [53][54][55][56][57][58]. The presence of OH radicals can be attributed to the water-rich atmosphere employed, whereas the remaining peaks associated with nitrogen and oxygen reactive species result from the presence of air in the reactor environment. ...
This study explores the impact of plasma treatment on Lavandin Grosso flowers and its influence on the extraction of essential oils (EOs) via hydrodistillation. Short plasma treatment times enhance the yield of EO extraction from 3.19% in untreated samples to 3.44%, corresponding to 1 min of plasma treatment, while longer treatment times (10 min) show diminishing returns to 3.07% of yield extraction. Chemical characterization (GC/MS and ATR-FTIR) indicates that plasma treatments do not significantly alter the chemical composition of the extracted EOs, preserving their aromatic qualities. Investigations into plasma–surface interactions reveal changes at the nanometer level, with XPS confirming alterations in the surface chemistry of Lavandin Grosso flowers by reducing surface carbon and increasing oxygen content, ultimately resulting in an increased presence of hydrophilic groups. The presence of hydrophilic groups enhances the interaction between the surface membrane of the glandular trichomes on Lavandin Grosso flowers and water vapor, consequently increasing the extraction of EOs. Furthermore, microscopic SEM examinations demonstrate that plasma treatments do not affect the morphology of glandular trichomes, emphasizing that surface modifications primarily occur at the nanoscale. This study underscores the potential of plasma technology as a tool to enhance EO yields from botanical sources while maintaining their chemical integrity.
... In the OES of Fig. 5, there are several peaks of N 2 FPS in the spectrum. The strong emission peak is at 670.5 nm due to the vibrational transition [ � − �� (Δ ) ] of 5-2 (+ 3) [53,54]. The other strong transition was at 632.3 due to a vibrational transition of 10-7 (+ 3) and at 716.5 due to a vibrational transition of 7-5 (+ 2). ...
Plasma-assisted nitrogen fixation has emerged as a promising alternative to conventional nitrogen fixation methods. In this study, we investigate the feasibility of plasma-assisted nitrogen fixation using an AC-driven dielectric barrier discharge generated from the micro-tips of a specially designed fast-modulated pyramid-shaped electrode. The obtained result is compared with the conventional flat electrode. Our results demonstrate that pyramid-shaped micro-tip electrodes can excite more nitrogen molecules than flat electrodes. Thus, pyramid electrodes have 58% more nitrogen oxides yield efficiency at 32% less energy cost. The highest nitrogen fixation is attained at 60% to 70% of oxygen concentration in nitrogen-feeding gas. These findings suggest that discharge through microtip is a promising and viable technology that could play a significant role in reducing the energy cost of the plasma-assisted nitrogen fixation method to meet the growing demand for sustainable nitrogen-based fertilizers.
... According to [60][61][62][63], at microwave discharges operated at atmospheric pressure, high dissociation rates of N 2 into atomic nitrogen (7) and O 2 into atomic oxygen (8) by electron collisions can be obtained even with low percentage concentrations of these gases. Besides, according to [56] nitrogen atoms with high kinetic energy can also be formed by dissociative recombination of N + 2 ions (9) [63,64]. ...
... ) are detected in the plume region (mainly in Zone III) (figure 5(c)) together with the emission of the NO γ band (figures 5(c) and (d)) with the reduced presence of charged particles suggests that the plume could behave as an afterglow (post-discharge) observed after N 2 -O 2 -based discharges, as has been extensively reported [59][60][61][62][63][64][65], although the non-negligible concentration of charged particles needs to be discussed. ...
The Torche à Injection Axial sur Guide d’Ondes source -better-known as TIAGO torch- is a particular type of Microwave Induced Plasma which has become in the technological and scientific spotlight due to its outstanding features. Moreover, TIAGO torch device arouses interest thanks to its remarkable performance in many challenging topics as green energy generation or graphene production by hydrocarbons decomposition. Although it has not been experimentally demonstrated up to date, discharges generated by a TIAGO torch have been theoretically predicted to be Surface Wave Discharges, a kind of plasmas leading the development of new materials. Therefore, a deeper and fundamental research of this device is needed to optimize the implementation of plasma technology to these fields. In this study, the axial distribution of gas temperature, electron density and intensity of main atomic and molecular emissions have been studied by Optical Emission Spectroscopy feeding the discharge with different input power values (200, 400 and 600 W). A complete axial characterization of both the dart and the plume regions is depicted and, according to the data obtained for the main plasma parameters, different regions can be identified, being the radiation zone reported for the first time at atmospheric pressure. The kinetics of both the dart and the plume are discussed and an experimental verification of the TIAGO torch behavior as a surface wave discharge is presented for first time.
... As shown in Fig. 10(a), the electron temperature can be determined by using the bandhead intensity ratio of the N 2 þ (B,0-X,0) transition at 391.4 nm to the N 2 (C,2-B,5) transition at 394.3 nm. 37 Figure 10(b) shows how this ratio depends on electron temperature. 38 To use this ...
Atmosphere-breathing electric propulsion (ABEP) systems capture atmospheric particles for use as propellant. In the best-case scenario, such systems can undertake long-life space missions without carrying propellant from the ground. The present research mainly focuses on plasma discharge processes based on inductively coupled plasma generation from atmospheric particles in very low Earth orbit (120-250 km). The optical diagnosis is done when the N 2 and O 2 mixture is injected into the low-pressure discharge chamber. Numerous active groups can be identified from the emission spectra, including excited molecules, molecular ions, atoms, and excited atoms. The generation mechanism of active groups is also clarified to understand the ionization process. The variations of plasma parameters are analyzed for different ratios of N 2 to O 2 , which can also be expanded to describe the potential behavior of ABEP systems in low Earth orbit. Note that this research is only a preliminary study and is not fully representative of the potential of ABEP systems. However, to develop ABEP systems, it is essential to understand the plasma behavior of discharge systems. Published under an exclusive license by AIP Publishing. https://doi.
... The typical molecular nitrogen bands and atomic nitrogen lines that appear in Fig. 9a and are ascribed to their respective species in Fig. 9c. the most prominent rotational-vibrational excitation bands are for the N 2 second positive system (C 3 Π u − B 3 Π g , (3,1), (4,3), [70,73,74]. Several atomic spectra lines appear at 744.2, 746.8, 776.2, 818.5, 820.0, 822.3, and 867.6 nm which may be ascribed to N I and 829.6 nm to N II [69]. ...
... This may suggest that N radicals are not the only main source of N-based precursor. One can speculate that N 2 metastable molecules in e.g., A 3 ∑ + state in the plasma may serve as a major reservoir for the nitrogen required for BNNS growth, these being abundant and especially known to be long-lived species having high energy (− 6 eV) [74]. ...
Boron nitride nanosheets (BNNS) were recently synthesized in a powder form using inductively coupled plasma through two readily-scalable bottom-up routes: (i) heterogeneous nucleation using amorphous boron particles and nitrogen, (ii) homogeneous nucleation from ammonia borane and nitrogen. The operating pressure was found to play a significant role in controlling the product purity and sheet dimensions in both routes. This work attempts to understand the effect of pressure by first presenting thermodynamic equilibrium calculations for the two systems at various pressures. From these, we estimate nucleation zones for BNNS and identify their possible major precursors. Computational fluid dynamics simulations (CFD) are then used to calculate plasma thermofluidic profiles by which axial residence times and gas cooling rates are estimated for the nucleation zones. Finally, in-situ optical emission spectroscopy (OES) is used to investigate the chemical composition of the gas during BNNS synthesis. It is found that the optimum pressure for the two routes is 62 kPa. The formation of BNNS heterogeneously follows a base-growth mechanism and requires the presence of liquid boron, B(liq) and N2/N/BN(g). The nucleation theory is used to explain the formation of BNNS homogeneously from BxNyHz critical clusters that grow into BNNS by the addition of BH/BN/NH onto the clusters. Thermodynamic equilibrium charts predict the formation of these species in their corresponding systems. Based on the species densities, BNNS formation/nucleation temperature ranges are proposed, e.g., around 2740–2350 K at the optimum pressure. The CFD simulation results at the formation/nucleation zones show that residence times and cooling rates control the formation of BNNS. These are found to be 12.4 ms and 34.1 × 103 K s−1, respectively, at the optimum operating pressure. OES spectra of both routes show the presence of several species consistent with the thermodynamic equilibrium results.
... Analysis of T vib from low vibrational levels of the N 2 SPS is very common in low pressure discharges [26,27] where the line intensities follow Equation (3). However, some reports of increasing pressure up to 10 Torr in a DC discharge [28], and up to 3 Torr in a microwave system [29] results in an overpopulation occurring in (at least) one of the C 3 Π u states. This overpopulation is attributed to energy pooling from metastable states (A 3 Σ + u ). ...
The design of a Very-High-Frequency (VHF) 162 MHz driven atmospheric-pressure Capacitively-Coupled-Plasma (CCP), with top and bottom electrodes operated in push-pull configuration, powered via a Power-Splitting-Transmission-Line-Driver (PSTLD), is presented. Application to the reprocessing of carbon dioxide into carbon-monoxide in this high” VHF atmospheric plasma is presented, demonstrating some behaviour of the plasma source. rf power in the system is characterized using measured current (∼ 1′s Amps peak) and voltage (∼ 10′s Volts peak) waveforms at the electrode; Both are sinusoidal confirming a glow-discharge operational condition. Analysis of Optical Emission Spectra results find a highly non-equilibrium plasma, with high vibrational temperatures (from N2) in the range ∼4000 K, while gas temperature, monitored by a thermocouple at the gas outlet, remains low ∼300 K, and confirmed by analysis of the N2 rotational bands. The relative density of CO produced, as a by-product of CO2 dissociation, is measured optically using N2 as an actinometer. The CO density increases with rf power and longer gas residence times in the plasma volume. The high VHF atmospheric plasma is found to operate in pure CO2 flows (no helium) with minimal gas heating for the full range of power densities (specific energy input of 0.4 to 2 eV per molecule) investigated.
... On the other hand, OES extrinsically probes the plasma and provides information about temperatures (electronic, vibrational, and/or rotational) and densities of excited species. Although being advantageous at first sight, this technique requires to make some hypotheses related to the energy distribution of the plasma species as well as the mechanisms of excitation [24,25]. ...
In this study, response surface methodology was applied to optimize the anti-fogging performance of coatings deposited on commercial glass samples from 1,3,5,7-tetramethylcyclotetrasiloxane (TMCTS)/N2O mixtures by atmospheric pressure plasma enhanced chemical vapor deposition. The effect of the dissipated power (DP), [N2O]/[TMCTS] ratio, and sample scroll speed on the anti-fogging performance was investigated by means of a Box-Behnken experimental design. The regression model relating transmittance of the coated glasses to these deposition parameters revealed that the anti-fogging performance strongly depends on the second-order interaction of the dissipated power and [N2O]/[TMCTS] ratio (i.e., DP × [N2O]/[TMCTS]). Contour plots showed that the dissipated power required to prepare optimal anti-fogging coatings should be of at least 0,7, 0,5 or 0,4 W cm⁻², if the [N2O]/[TMCTS] ratio in the plasma is 20, 30, or 40, respectively. When placed over water at 50°C, the coated glass samples allowed 80% (or more) of 590-nm light to pass through, thus meeting the minimal anti-fogging requirement for alpine skier goggles and faceshields. Despite not having a significant impact on the anti-fogging performance, the sample scroll speed is key to fabricating coatings with the desired thickness during in-line manufacturing.
... for the N 2 (X 1 Σ + g , v) levels, corresponding to a vibrational temper ature for the two first levels v = 0-1, T v = 2500 K and a gas temperature T g = 400 K [16]. Such a distribution is observed in N 2 microwave discharges and Levaton et al [17] have shown that the relaxation of the vibrational distribution of the X state during the off time of a pulsed discharge is low and the distribution remains nearly unchanged for 0.01 s after switch off in a nitrogen discharge operating at 665 Pa (5 torr), and T g = 400 K. ...
... πM CN [37]. The balance equation for C 2 N 2 is, (16) C 2 N 2so is the initial surface density of C 2 N 2 adsorbed. This equation can also be written as, ...
... Mass spectrometry signal intensity measured for hydrocarbide and nitrile compounds (m/z = 15,16,26,27,28,29,30 and 52) versus injected methane concentration. ...
A microwave discharge (2.45 GHz) is used to study the conversion of methane in a nitrogen afterglow. Investigations are performed both by means of emission spectroscopy and mass spectrometry.
We show that methane is injected in the ‘early afterglow’ of the nitrogen discharge where the energy transfer between and is the dominant process producing . Comparing experimental to theoretical results obtained for different vibrational levels v′ of the state at different pressures, we determined the reaction rate constant values corresponding to the energy transfer between and , assuming a Treanor distribution (Tr = 400 K, Tv0–1 = 2500 K) for the vibrational levels of . The reaction rate constant values range from 1.63 × 10⁻¹⁸ m³ s⁻¹ for v′ = 0 to 3.62 × 10⁻¹¹ cm³ s⁻¹ for v′ = 8. The mean value is equal to 1.93 × 10⁻¹⁷ m³ s⁻¹ when v′ ranges from 0 to 10.
The emission intensity decay of the first positive system is studied for bands corresponding to Δv = 3 versus methane concentration. The reaction rate constant value measured for the quenching of by CH4 is close to values proposed in literature in the case of collisions between and CH4. We studied the formation of CN, HCN and C2N2 species in the afterglow, comparing experimental to theoretical results and we measured the reaction rate constant value corresponding to:
(1) The production of HCN, by reaction of CH3 with N, k9 = 8.7 × 10⁻¹⁸ m³ s⁻¹.
(2) The production of CN, by reaction of CHx<4 with N, γk10 = 1.2 × 10⁻¹⁷ m³ s⁻¹, with γ = .
(3) The production of C2N2, we show that it is probably due to the reaction between gaseous and adsorbed cyanogen radicals on the reactor wall. The product of the reaction rate constant by the surface density of CN adsorbed is equal to k14(CNs) = 55 ms⁻¹.
(4) The global destruction of CN and C2N2 when CH4 in injected in the afterglow, k11 < 1 × 10⁻¹⁹ m³ s⁻¹ and k15 = 9 × 10⁻²⁰ m³ s⁻¹, respectively.
... Note that the [C, v 0 \ 4] calculated distributions have been found to be weakly influenced by the T g variations between 500 and 800 K. It is observed a high value of the N 2 (C, v = 1) density of the RF plasma which has been previously interpreted as a result of collisions between electrons and the N 2 (A) metastable molecules [27,28]. Table 1 reproduces the values of T g (see ''The plasma gas temperature'' section), h 1 (X), v T and N 2 (X, v = v T ) for the N 2 and Ar-20 %N 2 plasmas at 6 Torr, 100 W for RF where [N 2 ] RF = 7 9 10 16 cm -3 and at 8 Torr, 100 W for HF where [N 2 ] HF = 1.5 9 10 17 cm -3 . ...
We report a detailed comparison between RF and microwave (HF) plasmas of N2 and Ar–20 %N2 as well as in the corresponding afterglows by comparing densities of active species at nearly the same discharge conditions of tube diameter (5–6 mm), gas pressure (6–8 Torr), flow rate (0.6–1.0 slm) and applied power (50–150 W). The analysis reveals an interesting difference between the two cases; the length of the RF plasma (~25 cm) is measured to be much longer than that of HF (6 cm). This ensures a much longer residence time (10−2 s) of the active species in the N2 RF plasma [compared to that (10−3 s) of HF], providing a condition for an efficient vibrational excitation of N2(X, v) by (V–V) climbing-up processes, making the RF plasma more vibrationally excited than the HF one. As a result of high V–V plasma excitation in RF, the densities of the vibrationally excited N2(X, v > 13) molecules are higher in the RF afterglow than in the HF afterglow. Destruction of N2(X, v) due to the tube wall is estimated to be very similar between the two system as can be inferred from the γv destruction probability of N2(X, v > 3–13) on the tube wall (2–3 × 10−3 for both cases) obtained from a comparison between the density of N2(X, v > 3–9) in the plasmas to that of the N2(X, v > 13) in the long afterglows. Interestingly enough, densities of N-atoms and N2(A) metastable molecules in the afterglow regions, however, are measured to be very similar with each other. The measured lower density of N2+ ions than expected in the HF afterglow is rationalized from a high oxygen impurity in our HF setup since N2+ ions are very sensitive to oxygen impurity .
... The rotational temperature of the nitrogen FPS, T rot , is therefore assumed here to represent the gas temperature, T g . T rot is determined using a method described in ref 33. The method takes into account the strong dependence of the intensities of the band subheads at 773.8 and 775.2 nm on the rotational temperature of the nitrogen FPS for a given spectral resolution. ...
The long-term performance of many medical implants is limited by the use of inherently incompatible and bioinert materials. Metallic alloys, ceramics and polymers commonly used in cardiovascular devices encourage clot formation and fail to promote the appropriate molecular signaling required for complete implant integration. Surface coating strategies have been proposed for these materials but coronary stents are particularly problematic as the large surface deformations they experience in deployment require a mechanically robust coating interface. Here, we demonstrate a single step ion assisted plasma deposition process to tailor plasma-activated interfaces to meet current clinical demands for vascular implants. Using a process control-feedback strategy which predicts crucial coating growth mechanisms by adopting a suitable macroscopic plasma description in combination with non-invasive plasma diagnostics, we describe the optimal conditions to generate highly reproducible, industry scalable stent coatings. These interfaces are mechanically robust, resisting delamination even upon plastic deformation of the underlying material and were developed in consideration of the need for hemocompatibility and the capacity for biomolecule immobilization. Our optimized coating conditions combine the best mechanical properties with strong covalent attachment capacity and excellent blood compatibility in initial testing with plasma and whole blood, demonstrating the potential for improved vascular stent coatings.
